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Electropneumatic Positioner Type 3767 Edition October 1998 Mounting and operating instructions EB 8355-2 EN Fig. 1 Type 3767
Transcript
Page 1: positioner samson

Electropneumatic PositionerType 3767

Edition October 1998 Mounting and operating instructions

EB 8355-2 EN

Fig. 1 ⋅ Type 3767

Page 2: positioner samson

Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page

Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Versions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51. Design and principle of operation . . . . . . . . . . . . . . . . . . . . . . . 62. Attachment to control valve . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Mounting position and operating direction2.1 Direct attachment to the Type 3277 Actuator . . . . . . . . . . . . . . . . . . 92.2. Attachment according to NAMUR . . . . . . . . . . . . . . . . . . . . . . . 112.2.1 Mounting sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122.2.2 Presetting the travel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122.3 Attachment to rotary actuators . . . . . . . . . . . . . . . . . . . . . . . . . 142.3.1 Mounting the cam follower lever . . . . . . . . . . . . . . . . . . . . . . . . 142.3.2 Mounting the intermediate piece . . . . . . . . . . . . . . . . . . . . . . . . 152.3.3 Default setting of the cam disk . . . . . . . . . . . . . . . . . . . . . . . . . 163. Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193.1 Pneumatic connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193.1.1 Signal pressure indication . . . . . . . . . . . . . . . . . . . . . . . . . . . 193.1.2 Supply pressure regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . 193.2 Electrical connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193.2.1 Transistor relays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214.1 Presetting the positioner/actuator unit (direct attachment) . . . . . . . . . . . . 214.2 Adjusting the positioner at the control valve . . . . . . . . . . . . . . . . . . 234.2.1 Adjusting the proportional band Xp and the air delivery Q . . . . . . . . . . . 234.2.2 Adjustment with actuator: Actuator stem extends . . . . . . . . . . . . . . . . 244.2.3 Adjustment with actuator: Actuator stem retracts . . . . . . . . . . . . . . . . 244.3 Changing the operating direction . . . . . . . . . . . . . . . . . . . . . . . 254.4 Adjusting the limit switches . . . . . . . . . . . . . . . . . . . . . . . . . . 264.5 Adjusting the position transmitter . . . . . . . . . . . . . . . . . . . . . . . 285. Converting the positioner . . . . . . . . . . . . . . . . . . . . . . . . . . . 306. Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317. PTB certificate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328. CSA certificate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379. FM certificate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

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WARNINGAssembly, start-up and operation of the device may only be performedby trained and experienced personnel familiar with this product. According to these Mounting and operating instructions, trained person-nel is referred to persons who are able to judge the work they are as-signed to and recognize possible dangers due to their specialized train-ing, their knowledge and experience as well as their knowledge of therelevant standards.Explosion-proof versions of this device may only be operated by person-nel who have undergone special training or instructions or who are auth-orized to work on explosion-proof devices in hazardous areas.Any hazards which could be caused by the process medium, the signalpressure and moving parts of the control valve are to be prevented bymeans of appropriate measures.If inadmissible motions or forces are produced in the actuator as a resultof the level of the supply air pressure, this must be restricted by means ofa suitable pressure reducing station. Proper shipping and appropriate storage are assumed.

!

NoteDevices with model code 3767-x...x. 03 and up are equipped with ahinged cover without an opening for exhaust air.The required exhaust air connection is now integrated in the mountingequipment. Should these positioners be intended for attachment to oldactuator models, it is important to check whether there is an exhaust con-nection. If necessary, the mounting accessories must also be replaced.

!

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Technical dataPositioner

Travel range, adjustable

Angle of rotation

Direct attachment 7.5 to 30mm,Attachment according to DIN IEC 534 7.5 to 120 mm or

depending on type of cam disk 30 to 120°

Reference variableSignal range:Span:Coil resistance Ri for 20 °C

4(0) to 20 mA 8 to 20 mA

200 Ω

1 to 5 mA2 to 4 mA 880 Ω

Supply Air supply from 1.4 to 6 bar (20 to 90 psi)

Signal pressure pst (output) Limitable between approx. 2.5 to 6.0 bar (38 to 90 psi)

Characteristic LinearDeviation from terminal based conformity ≤1%

Hysteresis ≤0.3 %

Sensitivity ≤0.1 %

Operating direction Reversible

Proportional band Xp <1 to 2.5 % (proportional-action coefficient Kp: >100 to 40)

Air consumption For supply air = 1.4 bar≤280 ln/h

For supply air = 6 bar≤280 ln/h for min. adjust. press. regulator

Air delivery Actuator filled: 3.0 mn3/h

Actuator vented: 4.5 mn3/h

8.5 mn3/h

14.0 mn3/h

Perm. ambient temperature –20 to +80 °C (special version up to –40 °C), for Ex devices see Certificate of Conformity

Effects Temperature: ≤0.3 %/10 K Supply: ≤1 % between 1.4 and 6 barEffect of vibrations: none between 10 and 150 Hz and 4 g

Explosion protection Type of protection EEx ia IIC T6, see Certificate of Conformity

Degree of protection IP 54, (IP 65 special version)

Electromagn. compatibility Requirements acc. to EN 50081/50082 are met

Weight appr. 1 kg

Inductive limit switches

2 proximity switches Type SJ 2-SN

Control circuit Ratings according to the connected transistor relay

Switch. differ. for nom. travel ≤1 %

Solenoid valve

Input binary DC signal

Nominal signal 6 V DC 12 V DC 24 V DC

Signal 0 (no pickup), DC signal at –25 °C ≤1.2 V ≤2.4 V ≤4.7 V

Signal 1 (safe pickup), DC signal at +80 °C ≥5.4 V ≥9.6 V ≥18 V

Maximum permissible signal 28 V 25 V 32 V

Coil resistance Ri at 20 °C 2909 Ω 5832 Ω 11714 Ω

Air consumption in steady state, Kvs = 0.14 m3/h In addition to positioner: "Off" ≤60 ln/h; "On" ≤10 ln/h

Closing time for

for rated travel andsignal pressure range

Type 3277 Actuator cm2 120 240 350 700

0.2 to 1 bar

≤0.5 s

≤1 s ≤1.5 s ≤4 s

0.4 to 2 bar ≤2 s ≤2.5 s ≤8 s

0.6 to 3 bar ≤1 s ≤1.5 s ≤5 s

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Position transmitter — Intrinsically safe output circuit

Output signal Two-wire circuit 4 to 20 mA, reversible operating direction

Permissible loadRB =

US − 12 V20 mA

Power supply Voltage range 12 to 45 V DC Only with an intrinsically safe circuit

Performance Characteristic: Output linear to input, deviation from characteristic ≤1 %

Hysteresis ≤0.6 %

Response ≤0.1 %

Effect of power supply ≤1 % with voltage changes within the given limits

HF effect ≤0.1 %, f = 150 MHz, 1 W power output, 0.5 m distance

Effect of load ≤0.1 %

Permissible ambient temperature –25 to +70 °C –25 to ..s. Certificate of Conformity

Effect of ambient temperature ≤0.4 % on lower range value, ≤0.2 % on span

Ripple of output signal ≤0.3 %

Data referring to standard spring (15 mm travel for Type 3277 Actuator) and gain 100

VersionsElectropneumatic positioner Type3767- 0 0 0Ex protection

NoneEEx ia IIC T6CSA/FM

013

Accessory equipmentInductive proximity switchesNoneWith two Types SJ 2-SNSolenoid valveNone6 V DC12 V DC24 V DC

Analog position transmitter

02

6

0234

0Measuring spring 1Measuring spring 2

12

Pneumatic connection1/4-NPTISO 288/1-G 1/4

12

Electric connectionPG 13.5 bluePG 13.5 blackConnector HAN 7D(not CSA/FM approved)

12

4Reference variable

4 to 20 mA0 to 20 mA

12

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1. Design and principle of operationThe electropneumatic positioner is used toproduce a preselected relationship betweenthe valve stem position (controlled variable)and the controller output signal (referencevariable). It compares the electric outputsignal from a control device to the travel ofthe control valve and supplies a pressuresignal (manipulated variable) to the actuator.The positioner consists of an electropneumat-ic conversion unit (i/p converter) and a pneu-matic conversion unit equipped with a leverfor travel pick-off, a measuring diaphragmand a pneumatic control system with nozzle,diaphragm lever (flapper plate) and ampli-fier.The positioner is designed for either direct at-tachment to SAMSON Type 3277 Actuatorsor for attachment according to NAMUR(DIN/IEC 534) by means of an adapter hous-ing.The positioner can be additionally equippedwith either inductive limit switches and/or asolenoid valve or a position transmitter.The DC control signal of, e.g. 4 to 20 mAfrom the control unit is transferred to the elec-tropneumatic conversion unit (13) where it isconverted into a proportional pressure signalpe.The positioner operates according to the force-balance principle. The valve travel, i.e. thevalve position is transmitted via the pin (1.1)to the pick-off lever (1), determining the tor-sional force of the measuring spring (4). Thisforce is balanced against the positioning forcewhich is produced by the pressure pe on themeasuring diaphragm (5). If either the control signal or the valve posi-tion changes, the diaphragm lever (3) moves,changing the distance to the nozzle (2.1 or2.2) depending on the adjusted operating di-rection of the positioner. The air is supplied tothe pneumatic amplifier (10) and the pressureregulator (9). The controlled supply air is fedto the i/p module and then flows through theXp restriction (8) and the nozzle (2.1, 2.2)against the diaphragm lever (flapper plate). Any change of the reference variable or of

the valve travel results in a correspondingpressure change upstream and downstreamof the amplifier. The air (signal pressure pst)controlled by the amplifier flows through thevolume restriction (11) to the pneumatic actu-ator and causes the plug stem to move to aposition corresponding to the DC input signal(reference variable).The adjustable restrictions Xp (8) and Q (11)are used to optimize the positioner controlloop.The pick-off lever (1) and the measuringspring (4) are to be selected according to thenominal valve travel and the nominal refer-ence variable span.

Positioner with inductive limit switchesIn this version, the rotary shaft of the posi-tioner carries two adjustable tags which actu-ate the built-in proximity switches.

Positioner with solenoid valveWhen the positioner is equipped with a sole-noid valve, the relay can cause to overridethe positioner and open or close the valve(fail-safe positions). If a control signal corre-sponding to the binary signal "0" (off) is ap-plied to the input, the signal pressure pst isshut off and the actuator is vented. The actua-tor springs push the control valve in fail-safeposition.If a control signal corresponding to the bi-nary signal "1" (on) is applied to the input,the signal pressure pst is supplied to the actu-ator. The control valve is in control operation.

Positioner with position transmitterDue to the space requirements of the positiontransmitter, it is impossible to equip a positio-ner containing a position transmitter with in-tegrated limit switches or an integrated sole-noid valve. The position transmitter is used to ensure acertain relationship between valve position,i.e. valve travel, and a controller output cur-rent signal of 4 to 20 mA. As a result of theposition transmitter setting, both end posi-

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tions "valve closed" or "valve fully opened"respectively as well as all intermediate posi-tions are signalized. Since the valve position issignalized independently of the input signal to

the positioner, the position transmitter is asuitable option for checking the current valveposition.

4 3 7 8 9 11

13 6.1 6.2

7 8 9 10 11 12

6.1 4 6.2

2.13

2.2

5

1

1.1

1.2

Pe

Supply 9

V

PstQXp

pi

mA13

Travel

1 Pick-off lever1.1 Pin1.2 Clamp2.1 Nozzle >>2.2 Nozzle <>3 Diaphragm lever 4 Measuring spring5 Measuring diaphragm6.1 Span adjustment screw6.2 Zero adjustment screw7 Turnboard8 Xp restriction (gain) 9 Pressure regulator10 Amplifier11 Volume restriction12 Solenoid valve (option)13 i/p converter

Fig. 2 ⋅ Functional diagram and inside view

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2. Attachment to control valveYou can either attach the positioner directly toa SAMSON Type 3277 Actuator or to valveswith cast yokes or rod-type yokes accordingto NAMUR (DIN IEC 534) .When combined with an intermediate piece,you can also attach the device as rotary posi-tioner to rotary actuators.Since the positioner is also supplied as a basicunit without accessory equipment, youshould refer to the tables below for the re-quired mounting parts and order numbers re-spectively.You should remove the transportation coveron the positioner’s backside only directly be-fore attachment. Mounting position and operating directionThe operating direction of the positionerdetermines its mounting position to the actua-tor, as shown in Figs. 3, 4 and 6. The turnboard (7) at the positioner must bemounted correspondingly.For an increasing input signal (referencevariable), the signal pressure pst may beeither increasing (direct action >>) or de-creasing (reverse action <>). The same is truefor a decreasing reference variable.

Direct action >> results in a decreasing signalpressure, whereas reverse action <> results inan increasing signal pressure.On the turnboard (7), the operating direction isindicated by symbols (direct >> and reverse <>).Depending on the turnboard position, the ad-justed operating direction and its symbolbecome visible.If the required operating direction does notcorrespond with the visible symbol, or if youwant to change the operating direction,remove the fastening screw at the turnboard,turn the board by 180° and reinstall, usingthe screw.Make sure not to loose the three rubber sealsinserted in the housing.Any subsequent changes, such as reversingthe operating direction of the positioner con-trol loop or changing the actuator from "actu-ator stem extends" to "actuator stem retracts"or vice versa, result in a change of the posi-tioner’s mounting position.

Fig. 3 ⋅ Mounting position and signal pressure connection for Type 3277 Actuator (left)and for Type 3277-5 (right)

Actuator stem extends

Connection block

>> Operating direction <>Attachm. left Attachm. right

Internal signal pressure connection

Signal pressure tube

Actuator stem retracts

<> Operating direction >>Attachm. left Attachm. right

Switch-over plate

Signal pressure inputfor attachment left

Mark

Signal pressure input for attachment right

Actuator stemextends

>> Operating direction <>Attachm. left Attachm. right

Actuator stemretracts

<> Operating direction >>Attachm. left Attachm. right

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2.1 Direct attachment to the Type 3277ActuatorPositioner and actuator are available as oneunit and can be configured by the manufac-turer on the basis of the desired data suchthat they can be directly mounted to the con-trol valve (section 4.1.1).If you want to mount the positioner later, or ifyou want to change the actuator size or theoperating direction, you are required to ob-serve the correct combination of the requiredmounting parts for proper assembly by allmeans (see Figs. 3 and 4 as well as Tables 1to 4).Attachment — either left or right — dependson the required operating direction of the po-sitioner, >> or <>. For mounting, first screw the clamp (1.2) tothe actuator stem. Make sure that the fasten-ing screw is located in the groove of the actu-ator stem. Screw the associated lever D1 orD2 to the lever of the positioner. Fasten the distance plate (15) with the seal to-wards the actuator yoke.Place positioner on the plate such that leverD1 or D2 can slide centrically over the pin ofthe clamp.

Then, screw positioner to the distance plate(15).Install cover (16).For 240 to 700 cm2 actuators, you mustalign the lateral switch plate at the connectionblock (Fig. 4 below) with the arrow symbol onthe connection block, i.e. the actuator symbolfor either "actuator stem extends" or "actua-tor stem retracts" must correspond with therespective actuator model used. If not, removethe two fastening screws and the switch plate,turn switch plate by 180 degrees and rein-stall.Place connection block with the associatedseal rings against the positioner and the actu-ator yoke and screw tight using the fasten-ingscrew. For actuators with fail-safe action "actuatorstem retracts", additionally mount the pre- fabricated signal pressure line.Suspend the required measuring spring(Table 5) between diaphragm lever (3) andspan adjustment screw (6.1), using the outerslot.For 120 cm2 actuators (Type 3277-5), youmust align the hole in the distance plate with

1.2

D2

D1

15

Attachment left Attachment rightView onto signal pressure connection

Actuator stemretracts

Actuator stemextends

Switch-over plateSignal pressure hole

Switch plate

Mark

Venting

Type 3277 with 240 to 700 cm2 Type 3277-5 with 120 cm2

Fig. 4 ⋅ Mounting the clamp

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the seal located in the hole of the actuatoryoke when attaching the positioner. In addi-tion, you must remove the screw on the rearcover of the positioner (Fig. 5), and close thelateral signal pressure output "output" by meansof the plug contained in the accessory kit.With 120 cm2 actuators, the signal pressureis transmitted to the diaphragm chamber viathe switch-over plate (Fig. 4, right), and notvia connection block.Align the switch-over plate with the propersymbol and screw the plate tight.Important: If a solenoid valve or similardevice is attached to the 120 cm2 actuatorin addition to the positioner, do not re-move the M3 screw installed at the back ofthe positioner housing. Instead, the signalpressure must be fed from the signal press-

ure connection "output" to the actuator viaconnecting plate (Table 2). The black switch-over plate is no longer used.Filling the actuator with air: If the springchamber of the actuator must be filled withthe exhaust air of the positioner, you can con-nect the chamber (with version "actuator stemextends") with the connection block by meansof a tube (Table 3). For this purpose, removethe plug at the connection block. For version "actuator stem retracts" and Type3277-5 with a 120 cm2 actuator, the springchamber can be filled with air via an internalhole, which means no external tubing is re-quired.Important: If the control valve is installed, thelateral cover of the actuator must be mounted

Table 1 Actuator size Mounting kit

Required lever with associated clamp and distance plate cm2 Order no.

D1 (33 mm long with clamp 17 mm high) 120 1400-7116

D1 (33 mm long with clamp 17 mm high) 240 and 350 1400-6370

D2 (44 mm long with clamp 13 mm high) 700 1400-6371

Table 2 Order no.

Switch-over plate required for actuator size 120 cm2

or connection plate for additional attachment of, e.g. a solenoid valve G 1/8NPT 1/8

1400-68191400-68201400-6821

Connection block required for actuator size 240, 350 and 700 cm2

(including seals and fastening screw)G connection 1400-6955

NPT connection 1400-6956

Table 3 Actuator size cm2 Material Order no.

Required tube including screw joint for 240 Steel 1400-6444

actuator:

Actuator stem retracts or for filling the upper diaphragm chamber

240 Stainless steel 1400-6445

350 Steel 1400-6446

350 Stainless steel 1400-6447

700 Steel 1400-6448

700 Stainless steel 1400-6449

Table 4 Required measuring spring For actuator cm2 Travel mm Order no.

2 (4.5 threads) 120, 240 7.5 1400-6443

1 (9.5 threads) 120, 240 and 350 10 to 15 1400-6442

2 700 15 1400-6443

1 700 30 1400-6442

Accessories Gauge mounting block (for 120 cm2 only) G 1/4: 1400-7106 NPT1/4: 1400-7107

Gauge mounting kit for supply air and signal pressure SS/Brass: 1400-6950 SS/SS: 1400-6951

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such that the actuator’s venting plug is point-ing downwards.2.2 Attachment according to NAMUR (DINIEC 534)For positioner attachment according toNAMUR, you require an adapter housing.The valve travel is transmitted via the lever(18) and shaft (25) to the angle (28) of theadapter housing and then to the pin (27) lo-cated at the positioner lever.To ensure that the pin (27) lies properly to the Fig. 5 ⋅ Rear housing

Spring Screw

Attachment left Attachment right

Mounting position: View onto plate for travel pick-off (20), actuator on top (see also Fig. 7)

Actuator: Actuator stem extends (FA)

Direct operat. direction >> Reverse operat. direction <> Direct operat. direction >> Reverse operat. direction <>

Actuator: Actuator stem retracts (FE)

Direct operat. direction >> Reverse operat. direction <> Direct operat. direction >> Reverse operat. direction <>

Fig. 6 ⋅ Overview: Attachment acc. to NAMUR

20

Electrical connection Pneumatic connections Electrical connection

20

Pneumatic connection Electrical connections Pneumatic connection

Table 5 Control valve Travel mm With lever Order no.

NAMUR mounting kit

Parts, see Fig. 7

Valve with cast yoke7.5 to 60 N1 (125mm) 1400-6787

22.5 to 120 N2 (212 mm) 1400-6789

Valve withrod-typeyoke with

rod diameterin mm

20 to 25 N1 1400-6436

20 to 25 N2 1400-6437

25 to 30 N1 1400-6438

25 to 30 N2 1400-6439

30 to 35 N1 1400-6440

30 to 35 N2 1400-6441

Plus measuring spring acc. to Table 6 Measuring spring 1 (9.5 threads)Measuring spring 2 (4.5 threads)

1400-64421400-6443

Accessories Gauge mounting block G 1/4: 1400-7106 NPT 1/4: 1400-7107

Pressure gauge set SS/Brass: 1400-6950 SS/SS: 1400-6951

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angle (28), you must suspend the spring sup-plied with the accessory package at the backof the positioner housing as shown in Fig. 5.For positioner attachment you will need themounting parts listed in Table 5. The nominaltravel of the valve determines which lever andwhich measuring spring you have to use(Table 6).You can attach the positioner either to the leftor to the right side of the control valve (Figs. 6and 7). If you turn the positioner at the adapterhousing by 180 degrees, you can set orchange the operating direction of the posi-tioner/control valve unit.

2.2.1 Mounting sequence Choose the required mounting parts andmeasuring spring from Table 4 or 5.Control valve with cast yoke: Screw the plate(20) to the coupling of actuator and plug stemusing countersunk screws. With 2100 cm2

and 2800 cm2 actuators use additionalmounting bracket (32). Remove the rubberplug from inside the adapter housing andfasten housing on the left or right side of theNamur rib using a hexagon screw (see Fig. 6).Control valve with rod-type yoke: Screw theplate (20) to the carrier of the plug stem.Screw the studs (29) into the adapter hous-ing. Place the housing with the mountingplate (30) on either the right or left side (Fig.6) of the plug stem and screw on tight usingnuts (31). Make sure that the lever (18) to bemounted subsequently is in horizontal posi-tion at midtravel of the valve.Screw the pin (19) into the center row of holesof the plate (20) and lock it in a position

above the correct lever marking (1 to 2), seeTable 6.Clamp the clip (21) onto the lever (18) ac-cording to Fig. 7. If the actuator is attachedwith its air connection pointing to the front(Fig. 6), the clip must be clamped onto thelever (18) with the open side pointing down-wards.Plug the lever (18) together with the clampingplate (22) on the shaft (25). The clip must sur-round the pin (19).

2.2.2 Presetting the travelMove the valve to 50 % of travel. Adjust the shaft (25) in the adapter housingsuch that the black pointer (24) is alignedwith the cast marking on the adapter hous-ing. Screw clamp (22) tight in this positionusing the screw (23).Screw in the pin (27) at the positioner leveron the side of the insert nut and secure it witha hex nut on the other side. Note the mount-ing position A or B according to Table 6 andFig. 7.Put the positioner to the adapter housing,allowing for the correct mounting directionsuch that the pin (27) lies against the angle(28), as shown in Fig. 7.Screw the positioner to the adapter housing.Attention — pin must not slip out of the angleonce installed.Suspend the required measuring spring (Table 6)between the diaphragm lever (3) and thespan adjustment screw (6.1), using the outerinsert slot.Adjust positioner as described in section 4.2 .

Table 6

Travel mm *) 7.5 15 15 30 30 60 30 60 60 120

Pin on mark *) 1 2 1 2 1 2 1 2 1 2

Corresp. distance pin/lever fulcrum 42 to 84 mm 84 to 168 mm

With lever N1 (125 mm long) N2 (212 mm long)

Pin (25) in position A A B A B

Required measuring spring 2 1 1 1 1

*) Calculate intermediate values

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Fig. 7 ⋅ Attachment acc. to NAMUR (DIN IEC 534)

26 Lever of positioner27a Coupling pin27b Lock nut28 Angle29 Studs30 Plate31 Nuts32 Mounting bracket

18 Lever N1, N219 Pin20 Plate21 Clip22 Clamping plate23 Screw24 Pointer25 Shaft

26

28B

A

26 27a 28 29 3032

31

20

1918

18192021

2422 2523

27b

Mounting position of the pin

Venting

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2.3 Attachment to rotary actuators (Fig. 8)You can also attach the positioner to rotaryactuators according to VDI/VDE 3845 byusing the mounting kits and accessories listedin the tables below. In this arrangement, theactuator’s rotary motion is converted via thecam disk on the actuator shaft and the feelerroll of the positioner lever into the linearmotion required for the positioner’s pneu-matic control system. Attention: Use below table to check if theproper measuring spring (1 or 2) has beeninstalled!If you employ the positioner with double- acting springless rotary actuators, you arerequired to attach an amplifier with reversingrelay to the positioner (side of connections).In this case, you must turn the pressure regu-lator screw all the way to the right (clockwise),see also section 3.1.2.If you attach the positioner to SAMSON Type3278 Actuators, as shown in Fig. 8.1, thepositioner’s exhaust air is used to fill theactuator’s inside and the unused chamberbehind the diaphragm without the need forany additional tubing. If you attach the posi-tioner to actuators of other manufacturers(see Fig. 8.2), the chamber behind the dia-

phragm can be filled with air via a tube con-nection between actuator and intermediatepiece.

2.3.1 Mounting the cam follower leverPlace lever with roll (35) on the side of thetransmission lever (37) opposite from the in-sert nuts and secure with the supplied screws(38) and washers.Important: To ensure a close physical contactbetween the cam follower roll and the camdisk, suspend the spring contained in the ac-cessory kit 1400-6660 at the rear of the posi-tioner housing (see Fig. 5).

2.3.2 Mounting the intermediate pieceSAMSON actuator:Install adapter (36) at the free end of the rotaryactuator shaft. Attach intermediate piece (34)to the actuator housing using two screwseach. Align intermediate piece to ensure thatthe air connections of the positioner point to-wards the diaphragm housing. Align camscale as described in section 2.3.3 and fastenwith screws.

Table 7 Mounting parts complete, without cam disk

SAMSON Type 3278 Actuator 160 cm2 320 cm2 Other manufacturer’s actuator(VDI/VDE 3845)

Order no. 1400-7103 1400-7104 1400-7105

Required measuring springFor standard reference variable range: Spring 2 (4,5 threads)For split-range operation: Spring 1 (9,5 threads)

Order no.1400-64431400-6442

Reversing amplifier for double-acting springless actuatorsG threaded connectionNPT threaded connection

1079-11181079-1119

Cam disk with accessoriesCam disk , linear (0050-0080), opening angle 0 to 70°Cam disk , equal percentage (0050-0081), opening angle 0 to 70°Cam disk, linear characteristic (0050-0072), opening angle 0 to 90°Cam disk, equal percentage characteristic (0050-0073), opening angle 0 to 90°Cam disk , linear (0050-0074, Vetec), opening angle 0 to 56° to 0 to 75°Cam disk , equal percentage (0050-0075, Vetec), opening angle 0 to 44° to 0 to 75°

1400-67741400-67751400-66641400-66651400-66661400-6667

Accessories Gauge mounting block G 1/4: 1400-7106 NPT 1/4: 1400-7107

Pressure gauge set SS/Brass: 1400-6950 SS/SS: 1400-6951

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Actuators of other manufacturers:Install plate (42) at the actuator clamp. Placeintermediate piece on top of clamp andfasten with two screws. Push gasket overcoupling (44) and install on the actuatorshaft.Align cam disk (40) and scale as described insection 2.3.3 and fasten with screws.With springless actuators, you must screw thereversing amplifier (45) to the positioner

housing.For this purpose, install the supplied double-threaded nuts in the connection bores of thepositioner. Attach reversing amplifier with thehollow screws and the gasket to the posi-tioner, thereby assuring that the air fillingbore at the intermediate piece is covered.Depending on the direction of the rotary mo-tion, you must connect the actuator chamberswith the A1 and A2 outputs.

Fig. 8 ⋅ Attachment to rotary actuators

Venting 33 Positioner34 Intermediate piece35 Lever with feeler roll36 Adapter37 Transmission lever38 Screws39 Scale40 Cam disk42 Plate43 Clamp (turned 90%)44 Coupling45 Reversing amplifier

Fig. 8.1⋅ SAMSON Type 3278

Fig. 8.2VDI/VDE 3845

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2.3.3 Default setting of the cam diskThe cam disk’s default setting depends on thecontrol valve model used. Figs. 9.1 to 9.8show a linear cam disk as an example. Figs.9.1 to 9.4 refer to a control valve assemblywith a spring-loaded rotary actuator whichopens counterclockwise. The location of thesprings in the actuator determines the fail-safe position of the valve.Figs. 9.5 to 9.8 show the cam disk adjustmentfor a double-acting springless rotary actua-tor. The direction of rotation, either counter-clockwise or clockwise, depends on the actu-ator and valve model used. Starting point forall settings is the closed valve.You can set the operating action (direct >> orreverse <>) of the positioner, i.e. whether thevalve shall open or close with increasing ref-erence variable, at the turnboard (7).Each cam disk carries two cam sections. Thestarting point of each section is a small bore.Depending on the operating direction of therotary actuator — signal pressure opens orcloses valve — the starting point on the cam,either marked N (standard characteristic) or1 (reverse characteristic), must be directed to-wards the cam follower roll. The startingpoint can also be located on the back of thecam disk. In this case, turn over cam disk.

The starting point (bore) for the selectedcharacteristic must be aligned such that thecenter of rotation of the cam disk, the 0° po-sition on the scale, and the arrow mark onthe plate are in line.When you align the cam disk, install thedouble-sided scale disk so that the value onthe scale corresponds with the control val-ve’s direction of rotation.Important: The 0° position of the scale shouldalways correspond to the closed position. For actuators with fail-safe action: controlvalve open (OPEN) and for springless actua-tors, max. signal pressure must be applied tothe actuator before aligning the cam disk.Securing the aligned cam diskIf you want to additionally secure the camdisk to prevent it from being turned, you mustdrill a bore into the adapter (36) or the coup-ling (44) respectively, and install a 2 mmdowel pin. For this purpose, four bore holesare available on the cam disk that are locatedcentrically around the center bore hole. To in-stall the pin, select a suitable bore.

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Single-acting spring-loaded rotary actuator (Figs. 9.1 to 9.4)Linear cam diskEqual percentage cam disk represented by dot-dash lineControl valve opens counterclockwise(For control valves that open clockwise turn over the cam disk, so that the cam follower roll willgo over the same cam segments as shown in Figs. 9.1 to 9.4, but with the cam disk turning clock-wise)

Fail-safe position:

Control valve CLOSED without supply pressureOperating direction: direct >> Operating direction: reverse <>

Ref. variable Sig. press. Valve Characteris. Ref. variable Sig. press. Valve Characteris.

Increases Increases Opens N Decreases Increases Opens I

Fail-safe position:

Control valve OPEN without supply pressureOperating direction: direct >> Operating direction: reverse <>

Ref. variable Sig. press. Valve Characteris. Ref. variable Sig. press. Valve Characteris.

Decreases Decreases Opens I Increases Decreases Opens N

Fig. 9.1 9.2

9.49.3

90˚60˚

30˚ 0˚

90˚60˚

30˚ 0˚

Starting point I

Cam follower roll

Starting point N

Alignment at max. signal pressure

90˚60˚

30˚ 0˚

90˚60˚

30˚ 0˚

Starting point NCam follower roll Starting point I

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Double-acting springless rotary actuator with reversing amplifier (Figs. 9.5 to 9.8)Linear cam diskEqual percentage cam disk represented with dot-dash line

View on actuator shaft from positioner

Control valve opens counterclockwise Starting position: Control valve Closed

Operating direction: direct >> Operating direction: reverse <>

Ref. variable Sig. press. Valve Characteris. Ref. variable Sig. press. Valve Characteris.

Increases A1increas.A2 decreas.

Opens N Decreases A1increas.A2 decreas.

Opens I

View on actuator shaft from positioner

Control valve opens clockwise Starting position: Control valve Closed

Operating direction: direct >> Operating direction: reverse <>

Ref. variable Sig. press. Valve Characteris. Ref. variable Sig. press. Valve Characteris.

Increases A1increas.A2decreas.

Opens N Decreases A1increas.A2 decreas.

Opens I

9.5

9.7

9.6

9.8

90˚

60˚

30˚0˚

90˚

60˚

30˚

Starting point NCam follower roll Starting point I

90˚60˚

30˚ 0˚

90˚60˚

30˚ 0˚

Starting point NCam follower roll Starting point I

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3. Connections3.1 Pneumatic connectionsThe air connections are either NPT 1/4 orG 1/4 tapped holes. You can use customaryscrew joints for metal and copper tubes orplastic hoses. Make sure that the supply air isdehumidified and free of oil and dust. Adhereto the maintenance instructions for upstreampressure reducing stations. Thoroughly blowthrough all air tubes and hoses prior to con-necting them.For direct attachment to the Type 3277Actuator, there is a fixed output pressure con-nection. For NAMUR attachment, the signalpressure is connected to either the upper orlower diaphragm chamber of the actuator,depending on the actuator’s fail-safe action,"actuator stem retracts or extends".Exhaust air:Positioners with the model code 3767-x...x.03 and up are equipped with a hinged coverwithout an opening for exhaust air. The ex-haust air connections for these models arenow included in the mounting accessories.For direct positioner attachment, the vent-ing plug is located on the plastic cover ofthe actuator, for attachment according toNAMUR it is located on the adapter housingand for attachment to rotary actuators on the in-termediate piece, i.e. the reversing amplifier.Important: If you intend to replace oldermodels with model codes up to 3767-x...x.02, you will have to replace the mountingparts as well, if required.

3.1.1 Signal pressure indicationFor exact positioner adjustment, we recom-mend that a pressure gauge (direct attach-ment) or a gauge assembly (NAMUR attach-ment) for signal pressure indication be at-tached. These parts are listed as accessoriesin Table 4, 5 or 7 respectively.

3.1.2 Supply pressure regulatorThe required supply pressure is dependent onthe actuator version used. With "actuator

stem extends" (FA), it should be 0.4 bar abovethe upper signal pressure range value (seename plate), and with "actuator stem retracts"(FE), it should be 0.4 bar above the requiredsignal pressure (calculated according to sec-tion 4.2.3). After tilting the cover plate (9) away, you canadjust the pressure regulator infinitely. Whenthe adjuster is turned all the way to the left,signal pressures for spring ranges are regu-lated up to 2.5 bar. When the adjuster isturned all the way to the right, signal press-ures for spring ranges are regulated up to 6.0bar. If the signal pressure must not exceed acertain value, this limit value can be regu-lated by means of a pressure gauge (acces-sory).

3.2 Electrical connectionsFor electrical installations, you are re-quired to observe the relevant electro-technical regulations and the accidentprevention regulations of your country.In Germany, these are the VDE regula-tions and the accident prevention re-gulations of the liability insurance as-sociation.For assembly and installation in haz-ardous areas, you are required to ob-serve EN 60079-14:1997; VDE 0165Part 1/8.98.For connection of the intrinsically safecircuits, the Certificate of Conformityapplies.

!

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Connect the wires for the reference variableto the terminals 11 and 12. A general con-nection of the positioner to a bonding con-ductor is not required. Should it be necessary,however, you can connect this conductoreither inside or outside of the housing. ForEx plants, refer to VDE 0165, section 5.3.3 .Depending on the model, the positioner isequipped with inductive limit switchesand/or a solenoid valve. You cannot use these accessories in posi-tioner versions with position transmitter. Theposition transmitter is operated in a two-wirecircuit. The supply voltage is usually 24 V DC.Under consideration of the resistance of thesupply leads, the voltage at the positiontransmitter terminals must be minimum 12 Vand is not to exceed 45 V DC.For terminal assignment, refer to Fig. 10 orthe label on the terminal strip.Note on the selection of cables and wires: To run several intrinsically-safe circuits in amulti-core cable, observe the section 12 ofEN 60079-14; VDE 0165/8.98.Note especially that for commonly used insu-lating materials, such as polyethylene, theradial thickness of the conductor insulationmust be minimum 0.2 mm. The diameter of asingle wire of a flexible conductor must not be

smaller than 0.1 mm.Take care to protect the conductor endsagainst unlaying, e.g. by using wire end fer-rules. For connection via 2 separate cables,you can mount an additional cable gland.Cable gland PG 13.5Black Order no. 1400-6781Blue Order no. 1400-6782Adapter PG 13.5 to 1/2" NPT:Metallic Order no. 1400-7109Blue finish Order no. 1400-7110

3.2.1 Isolating switch amplifierFor operation of the inductive limit switches,isolating switch amplifiers must be connectedin the output circuit. Their function is to con-trol the limit values of the control circuit acc.to NAMUR so that operational reliability ofthe positioner is ensured. If the positioner isinstalled in hazardous areas, you are re-quired to observe the relevant regulations.For connection to the limit switches we recom-mend isolating switch amplifiers by "Pepperlund Fuchs".

Rear connections

Isolating switch amplifieracc. to DIN 19 234

mAControl signal

6 to 24 V DCSolenoid valve

mAControl signal

Power supply unit

Version with position transmitter

Fig. 10 ⋅ Electrical connections

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4. Operation4.1 Preadjusting the positioner / Type 3277actuator unit (direct attachment) If you need to check the adjustment of thecombined positioner/actuator unit after thereference variable or the signal pressurerange has been changed, note that the pro-cedure for the version "actuator stem extends(FA)" is different from that for version "actua-tor stem retracts (FE)". Proceed as follows:Connect an appropriate current source to thecontrol signal input, a pressure gauge (op-tional accessory, Table 4) to the signal press-ure connection at the connection block, andthe supply air to the associated supply airinput (note section 3.1.2).Use the enclosed adjustment template tomeasure the travel (on option also a slidegauge). The template (see Fig. 11) must beplaced on the threaded stem of the actuator. Read off the signal pressure range and nomi-nal travel from the name plate. Example: A reference variable of 4 to 20 mAwith direct operating direction >> or of 20 to4 mA with reverse operating direction <> isto be assigned a travel of 0 to 100 % = 15mm with a signal pressure range of 0.2 to 1bar.

Set the volume restriction Q (11) to medium(approx. 4 revolutions from the closed posi-tion), with large actuators to completelyopen. Set the Xp-restriction (8) to medium (1/2 rev-olutions).Check the actuator for vibrations by brieflypressing the diaphragm lever (3), and openthe Xp-restriction a bit more, if necessary.

Actuator stem extends FADirect operating direction >>:Adjust the reference variable to 4 mA usingthe current source. Turn the zero adjustmentscrew (6.2) until the actuator stem has com-pletely extended and is just starting to retract.Align the adjustment template (Fig. 11) suchthat the lower travel mark is aligned with theend of the actuator stem.Set the input signal to 20 mA and turn thespan adjustment screw (6.1) until the end ofthe actuator stem is aligned with the uppertravel mark.Set the input signal to 4 mA again and turnthe zero adjustment screw (6.2) once moreuntil the pressure gauge indicates the lowervalue of the signal pressure range.Mount the actuator on the control valve as de-scribed in section 4.1.1, and adjust it accord-ing to section 4.2.

Actuator stem extends FAReverse operating direction <>:Adjust the input signal to 4 mA using the cur-rent source. Turn the zero adjustment screw(6.2) until the actuator stem has completelyretracted and is just starting to extend.Align the adjustment template (Fig. 11) suchthat the lower travel mark is aligned with theend of the actuator stem.Set the input signal to 20 mA and turn thespan adjustment screw (6.1) until the end ofthe actuator stem is aligned with the uppertravel mark.Leave the input signal at 20 mA and turn thezero adjustment screw (6.2) until the pressuregauge indicates the lower value of the signalFig. 11 ⋅ Preadjustment with template

30

15

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pressure range.Mount the actuator to the control valve as de-scribed in section 4.1.1, and adjust it accord-ing to section 4.2.

Actuator stem retracts FEDirect operating direction >>:Adjust the input signal to 4 mA using the cur-rent source and turn the zero adjustmentscrew (6.2) until the actuator stem has com-pletely retracted and is just starting to extend.Align the adjustment template (Fig. 11) suchthat the lower travel mark is aligned with theend of the actuator stem.Set the input signal to 20 mA, turn the spanadjustment screw (6.1) until the end of the ac-tuator stem is aligned with the upper travelmark. Leave the input signal at 20 mA and turn thezero adjustment screw (6.2) until the pressuregauge indicates the upper value of the signalpressure range.Mount actuator on the control valve as de-scribed in section 4.1.1, and adjust it ac-cording to section 4.2.

Actuator stem retracts FEReverse operating direction <>:Adjust the input signal to 4 mA using the cur-rent source and turn the zero adjustmentscrew (6.2) until the actuator stem has com-pletely extended and is just starting to retract.Align the adjustment template (Fig. 11) suchthat the lower travel mark is aligned with theend of the actuator stem.Set the input signal to 20 mA, turn the spanadjustment screw (6.1) until the end of the ac-tuator stem is aligned with the upper travelmark. Set the input signal to 4 mA again and turnthe zero adjustment screw (6.2) until thepressure gauge indicates the upper value ofthe signal pressure range.Mount actuator to the control valve as de-scribed in section 4.1.1, and adjust it accord-ing to section 4.2.

46

47

48

49

100%

0%

4 20 mA12

4 20 mA

100%

0%

< > < <

< > < <

Reference variableInput signal

Dead band

Valve 2 Valve 1

Open

Travel

Closed

Open

Travel

ClosedFig. 12 ⋅ Actuator attachment

Fig. 13 ⋅ Standard operation (top) and split-range operation with two valves of opposed operation

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4.1.1 Mounting the actuator to the valve Loosen coupling nut (48) and lock nut (49) atthe plug stem and push the stem into the seatuntil the plug stop is reached. Screw thecoupling and lock nut down the plug stemthread.Place actuator on the valve bonnet andtighten it with a ring nut (46).Connect supply air and electric control signalto the positioner.With "actuator stem extends (FA)", operatingdirection >> and "actuator stem retracts(FE)", operating direction <>, set the refer-ence variable to the lower range value (4mA).With "actuator stem extends (FA)", operatingdirection <>, and "actuator stem retracts(FE)", operating direction >>, set the refer-ence variable to the upper range value (20mA).Then screw up coupling nut until it touches theactuator stem, and tighten the lock nut (49).Put the coupling halves (47) around the stemand screw them tight.

4.2 Adjusting the positioner at the controlvalveStarting and reference variableWhen you adjust the positioner at the controlvalve assembly, you must adapt the valvetravel (opening angle) to the reference vari-able. With a reference variable of, e.g. 4 to 20mA, the valve must pass through its entiretravel range of 0 to 100 % (Fig. 13). For rotary positioners, you must assign anopening angle of, e.g. 0 to 70° to the refer-ence variable.The starting is defined with regard to theclosed position of the valve. Depending on the actuator version ("actuatorstem extends (FA)" or "actuator stem retracts(FE)" and the operating direction of the posi-tioner (>> or <>), this starting can be repre-sented by either the lower or upper rangevalue (4 or 20 mA) of the reference variable.The reference variable range and thus the

upper range value determine the travel of thevalve.In the case of split-range operation (Fig.13), the control valves operate with lower ref-erence variables. The controller output signalused for controlling two control valves isdivided such that the values pass the com-plete travel range at half an input signalrange each (e.g. first valve set to 4 to 12 mAand second valve to 12 to 20 mA). To avoidoverlapping, take a dead band of ±0.5 mAinto account, as shown in Fig. 13.You can adjust the starting (zero) at screw(6.2), the span and thus the upper rangevalue is adjusted at screw (6.1).For adjustment, connect a suitable currentsource to the signal input and the supply airto the associated supply air input. Important:When the positioner is controlled by a com-puter generating a signal limited between,e.g. 4 to 20 mA, it is advisable to set the posi-tioner to the range 4.5 to 20 mA. Only then isit ensured that the actuator is completelyvented and that the valve is completely closedat a computer signal of 4 mA.(Accordingly, set range to 4 to 19.5 mA foroperating direction <>.)

4.2.1 Adjusting the proportional band Xpand the air delivery QFirst, adjust the reference variable to approx.50 % of its range. Then, turn zero adjustmentscrew (6.2) until the valve is at about mid-travel. Set the volume restriction Q (11) to medium,with large actuators, open completely.Set the proportional band Xp at the adjuster(8) to medium (1/2 revol.).Check the valve for vibrations and the po-sitioning rate by briefly touching the dia-phragm lever (3), and readjust the Xp-re-striction, if necessary.Important: Always adjust the Xp-restrictionprior to adjusting the starting point. Latermodifications would result in a zero shift!

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4.2.2 Adjustment with actuator:Actuator stem extends (FA)Starting point (e.g. 4 mA)Set the input signal to 4 mA using a currentsource.Turn zero adjustment screw (6.2) until thecontrol valve is just leaving the initial posi-tion. Take away the input signal and slowlyincrease it, thereby checking if the valve startsto move at exactly 4 mA. Correct any devia-tion at the zero adjustment screw (6.2).Upper range value (e.g. 20 mA)After the starting point has been set, increasethe input signal to 20 mA using a currentsource. At exactly 20 mA, the plug stem muststand still and have passed through 100%travel (watch the travel indicator at thevalve!). If the upper range value is incorrect,the span adjustment screw (travel) must beturned (4 revolutions equal a travel change of10 % in standard operation. In split-rangeoperation, this value is halved).The travel decreases if you turn the screwclockwise and it increases if you turn itcounterclockwise.After corrections have been made, take awaythe control signal and increase it again. First,check starting point. Then, check upperrange value. Repeat this procedure until bothvalues are correct.Important: When the zero adjustment screw(6.2) is adjusted, check whether the actuatoris without pressure.With an input signal of 4 mA and operatingdirection <>, the pressure gauge must indi-cate 0 bar. Correct zero accordingly!

4.2.3 Adjustment with actuator:Actuator stem retracts (FE)Important: With actuators "actuator stemretracts (FE)" and at an upper referencevariable range value of 20 mA and opera-ting direction >>, and at the lower input rangevalue of 4 mA and operating direction <>,the diaphragm chamber must be providedwith a pressure high enough to shut thevalve tight, even in the event of an up-

stream system pressure. (The required signal pressure can be read offfrom the label on the positioner.)You can use the following formula to calculatethe required signal pressure:

Req. signal press. [bar] = d2 π ∆p

4 A + Fbe + 0.4

d = Seat diameter [cm]∆p = Differential pressure p1 – p2 [bar]A = Actuator area [cm2]Fbe = Upper spring range value of the

actuator [bar]If there are no specifications, calculate as fol-lows:Required signal pressure = Upper springrange value + 1 barStarting point (e.g. 20 mA)Set the input signal to 20 mA using the cur-rent source. Turn zero adjustment screw (6.2)until the valve is just leaving the initial posi-tion. Increase the input signal and slowlylower it to 20 mA. Check if the valve startsmoving at exactly 20 mA. Correct any devia-tions at the zero adjustment screw (6.2). Thevalve leaves its end position earlier if you turnthe screw counterclockwise and later if youturn it clockwise. Upper (range) value (e.g. 4 mA)After the starting point has been set, increasethe input signal to 4 mA using the currentsource. At exactly 4 mA, the plug stem muststand still and have passed through 100%travel (watch travel indicator at the valve!). Ifthe upper range value is incorrect, the spanadjustment screw (travel) must be turned (4revolutions equal a travel change of 10 %with standard operation. Halve this value forsplit-range operation.). To decrease the travel, turn the screw clock-wise and to increase the travel, turn it counter-clockwise. After corrections have been made, reset inputsignal to 20 mA. Turn the zero adjustmentscrew (6.2) once more until the gauge indi-cates the required signal pressure.

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Important: After having attached and ad-justed the positioner, make sure that the ventplug in the cover is directed downwardswhen the valve is installed in the plant.

4.3 Changing the operating directionIf you want to change the operating directionafter it has already been set, you must alterthe turnboard (7), the position of the connec-tion block, the positioner and the clamp (1.2)for direct attachment (Fig. 3). In the case of NAMUR attachment, the turn-board (7) and the positioner must be turnedat the adapter housing (Fig. 6). For rotary positioners, the cam disk must beassigned anew according to Fig. 9.How to change the position of the turnboard(7) is described in section 2 "Mounting posi-tion and operating direction".

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4.4 Adjusting the limit switchesThe positioner version with inductive limitswitches has two adjustable tags mounted ona rotary axis which operate the associatedproximity switches (50).To operate the inductive limit switches, youmust connect the corresponding isolatingswitch amplifier in the output circuit (see sec-tion 3.2.1). When the tag (51) is in the induc-tive field of the switch, the switch assumes ahigh resistance. When it is no longer in thefield, the switch assumes a low resistance. The limit switches are usually adjusted suchthat they provide a signal in both limit posi-tions. The switches, however, can also be ad-justed to signalize intermediate positions.The assignment of the switches A and B mustbe determined according to Tables 9 and 10.It depends on the operating direction, themounting position of the positioner, and thelimit position of the control valve (either valveOpen or Closed). Assignment of the terminal pairs 41/42 and51/52 to the switches A and B

can be achieved by turning the associatedname plate located on the terminal block (seealso Fig. 10).Important: Since the tags of the limit switchescannot be turned by 360°, proper assign-ment of the switches A and B to the valve po-sitions Open and Closed must be observed,especially when the limit switches are to beconnected in fail-safe circuits. The desired switching function, i.e. whetherthe output relay must be picked up or re-leased when the tag has entered the field, hasto be determined by means of jumpers foreither working current or closed circuit cur-rent at the isolating switch amplifier. Setting the switching point: Move the valve to the switching position andadjust the tag by turning the adjustmentscrew (53) in such a way that the switchingpoint is reached and is indicated by the LEDat the transistor relay. To ensure safe switching under any condition-s, the switching point should be adjusted to avalue of approx. 2 % before the mechanicalstop (Open — Closed).

Fig. 14 ⋅ Limit switch

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Table 8 Direct attachment to Type 3277 Actuator (Fig. 3)

Attachment left Attachment right

Proximity switch

Valve position Tag OUT Tag IN Tag OUT Tag IN

Closed B A A B

Open A B B A

Table 9 Namur attachment either right or left (Fig. 6)

Actuator stem extends (FA) Actuator stem retracts (FE)

Operatingdirection

Valve position

Proximity switchTag Operating

directionValve

position

Proximity switchTag

OUT IN OUT IN

>> ClosedOpen

BA

AB

>> ClosedOpen

AB

BA

<> ClosedOpen

AB

BA

<> ClosedOpen

BA

AB

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4.5 Adjusting the position transmitterImportant: Prior to adjusting the positiontransmitter, you have to adjust startingpoint (zero) and upper range value (span) ofthe positioner. Depending on the position of the 7-pin plug(symbols on plug facing upwards: >> or <>),you can set the feedback signal to either arange of 4 to 20 mA or 20 to 4 mA for 0 to100 % travel. Zero point (ZERO)Use switches 1 and 2 to preset the zeropoint and use the ZERO potentiometer forfine-tuning. The adjusted value is alwaysrelated to 4 mA.Span (SPAN)Use switches 3 and 4 to preset the span, i.e.the upper range value, and use the SPANpotentiometer for fine-tuning. The adjustedvalue is always related to 20 mA.

Example:Move valve to the open position, observingthe position transmitter signal.If the signal does not move in the desired di-rection, switch over multipin plug. Then adjust zero point (4 mA) and span (20mA) for the valve positions according toTable 10.

Adjusting the zero pointMove valve via the input signal of the posi-tioner to the closed position (valve CLOSED— travel 0 %).The ammeter must now indicate a currentvalue of approx. 4 mA. Correct smaller devi-ations at the ZERO potentiometer until themeter shows exactly 4 mA.If deviations are too high and cannot be ad-justed at the potentiometer (adjustment rangeapprox. 20 revolutions), switches 1 and 2must be set in a way that a mA value is indi-cated which lies within the adjustment rangeof the ZERO potentiometer. Subsequently, ad-just zero point with the ZERO potentiometerto precisely 4 mA.

ZEROSPAN

12

34

SPAN

ZERO

Fig. 15 ⋅ Position transmitter

Table 10 Position transmitter

Valve position Observed feedback signal Signal direction Adjust zero point/span to

Open

Closed

Current increases ↑

OK 20 mA 4 mA

Valve OPENValve CLOSED

Not OK→ Reconnect plug

4 mA20 mA

Valve OPENValve CLOSED

Current decreases ↓

OK 4 mA20 mA

Valve OPENValve CLOSED

Not OK→ Reconnect plug

20 mA 4 mA

Valve OPENValve CLOSED

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Adjusting the spanMove valve via input signal of the positionerto the fully opened position (valve OPEN —travel 100 %).The ammeter must now indicate a current valueof approx. 20 mA. Correct small deviations atthe SPAN potentiometer until the ammetershows exactly 20 mA. If deviations are too high,switches 3 and 4 must be set in a way that a mAvalue is indicated which is within the adjust-ment range of the SPAN potentiometer. Sub-sequently, adjust SPAN potentiometer until theammeter shows exactly 20 mA.Since the adjustment of zero point and spanslightly influence one another, you have toreadjust the potentiometer until both valuesare correct.

Note on adjustment of the position transmit-ter for positioners with NAMUR adapterhousing:If the positioner and the position transmittersignal have different operating directions(<< and >>), the zero point of the trans-mission signal could be unadjustable. This isdue to the additional deviation caused by theangle (28) of the adapter housing.If so, readjust the black pointer (chap. 2.2.2on page 12) so that the sensor of the positiontransmitter can reach the control range.Proceed as follows:Unscrew the clamping plate.For "Actuator stem extends" FA, shift thepointer in upward direction towards the ac-tuator.For "Actuator stem retracts" FE, shift the poin-ter in downward direction towards the valve.For valves with rod-type yoke, however,slightly shift the positioner on the rod in up-ward (FA) or downward (FE) direction.

Important: When you perform any of theabove changes, zero and span of the positio-ner require readjustment. This must be donebefore you calibrate the position transmitter.

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5. Converting the positioner (Fig. 16)You can convert the electropneumatic posi-tioner to a Type 3766 Pneumatic Positionerusing the following conversion kit: Housing with electric connection PG 13.5Order no. 1400-7115Remove support with terminal base and discon-nect cable to i/p module.Unscrew fastening screws and remove i/p mo-dule (6) including seals (7, 8).

Place connecting plate (3) with seal overhousing bore holes and screw tight, so thatthe restriction in the seal is located above theright inside bore hole. Replace cable gland (5) with pneumaticscrew gland (1).Connect silicone hose (2) and insert guardplate (4) in the housing.Reattach support with terminal base.Change Type no. (model no.) on name plateto Type 3766.For the Type 3766 Positioner, refer to the"Mounting and operating instructions"EB 8355-1EN.

1 2 3 45 6 7 8

Fig. 16 ⋅ Conversion to pneumatic positioner

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9. Dimensions in mm

44

19.5

3539

164

4676 50

36N

1=11

3 N

2=20

0

5856

68

28

1429

150

16419.5

31

6818

5

76

110

82

5666

54

PG 13.5

28.5

28.5

Output 1 (A1)

Output 2 (A2) Supply (Z)

50

Output (36)

Supply (9)

Reversing amplifier(optionally)

Attachment according to DIN IEC 534 (NAMUR) with adapter housing

Fulcrum ofactuator shaft

Pneumatic connectionsG 1/4 or NPT 1/4

Directattachment

Pneum. connection of reversing amplifier

31

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1) SEV Approval No. 93.1 00906.04

6. PTB Certificate of Conformity for Type 3766-1 1)

32

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33

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34

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35

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36

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7. CSA certificate

37

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38

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8. FM certificate

39

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40

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SAMSON AG ⋅ MESS- UND REGELTECHNIKWeismüllerstraße 3 ⋅ D-60314 Frankfurt am MainTelefon (0 69) 4 00 90 ⋅ Telefax (0 69) 4 00 95 07Internet: http://www.samson.de S/

CD

01.

99

EB 8355-2 EN


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