Nuclear  Division    Scientech  Instrumentation  &  Controls  

1350  Whitewater  Drive  Idaho  Falls,  Idaho  83402  

Scientech-­‐I&C-­‐Sales@CurtissWright.com  http://scientech.cwfc.com  

 

 Modern  Analog  Safety  System    Nuclear  plant  safety  systems  have  simple   functions.  They  monitor  a  small  number  of   inputs  and  produce  a  small  number  of  outputs,  using  fairly  simple  functions.    The   first  wave  of  US  commercial  nuclear  power  plants  peaked  in  1974.    These  plants  were  provided  with  highly  reliable,   long  lived,  analog  safety  systems.    Analog  lines  like  Foxboro©  H-­‐Line,  Hagan©  7100,  GEMAC©  5000,  and  Foxboro  Spec200©  all  provided  safe,   reliable,   cyber-­‐immune   operation   for   35   to   40   years  before  the  failure  rates  began  to  climb  and  replacements  were  made.    Scientech   re-­‐engineered   replacements   for   many   of   these   systems,   building   an   expertise   in   analog   process  instrumentation  design   that   is   unsurpassed   today.    However,   the   re-­‐engineered   replacements  were   designed   to  duplicate  the  1970’s  technology  of  the  original  equipment.    Today,  Scientech  would   like  to  continue  the  excellent  performance  record  of  analog  safety  systems  by  offering  a  new  Modern  Analog  Safety  System   (MASS),  based  on  today’s  technology,  while  maintaining  the  best  qualities  of  the  legacy  systems.  

• Easy  to  understand    -­‐  Like  the  legacy  systems,  the  MASS  is  partitioned  into  simple  modules  –  analog  and  contact   input   modules,   summer   modules,   multiplier   modules,   divider   modules,   square   root   extractor  modules,  alarm  modules,  analog  and  contact  output  modules  

• Highly   Accurate   –   The   typical   MASS   module   has   an   accuracy   of   ±   0.05%   span,   and   a   total   device  uncertainty  including  120  day  drift  of  ±  0.10%  span.    This  is  approximately  five  times  more  accurate  than  typical  legacy  modules.  

• Extremely  Stable  –  With  a  ±0.05%  drift  over  120  days,  recalibrations  will  be  few  and  far  between.  

• Lower  Cost  –  Modern  surface  mount  technology  allows  circuit  board  production  at  a  fraction  of  the  cost  of  the   older,   through-­‐hole   technology.     Scientech   will   pass   this   savings   on   to   our   clients;   a   typical   MASS  module  costs  less  than  half  of  a  re-­‐engineered  replacement  module.  

• Long  Life  –  The  analog  systems  provided  in  the  1970s  lasted  well  into  the  2000s  –  35  to  40  years  of  reliable  life.     In   the   last   40   years,   electronics   has   only   gotten  more   reliable,   and   a  MASS   system   has   a   40   year  design  life.  

• Obsolescence   Proof   –   Digital   technology   is   driven   by   the   consumer   marketplace,   with   its   apparently  insatiable   demand   for   smaller,   faster,   and  more  powerful   electronics.     Analog   technology,   on   the  other  hand,   is   industry   driven,   and   is   stable   and  backwards   compatible.     Scientech   I&C  will   always  be   able   to  make  MASS  modules  with  analog  components  –  there  are  no  microprocessors  or  families  of  digital  chips  to  go  obsolete.    

• Cyber   Secure   –   An   analog   system   is   NOT   a   Critical   Digital   Asset.     There   is   no   existing   or   future   cyber  security  threat,  since  there  is  no  computer  control  of  any  aspect  of  any  safety  function.  

Copyright  ©  2013  Scientech.  No  part  of  this  document  may  be  copied,  modified,  deleted  or  expanded  by  any  process  or  means  without  prior  written  permission  from  Scientech.  R*Time  is  a  registered  trademark  of  Scientech.  

 

• Easy  to  License  –  The  US  NRC  has  reviewed  the  MASS  provided  to  Crystal  River  before  the  decision  to  shut  down  the  plant.    Like  the  legacy  analog  systems,  the  review  was  based  on  SRP  7.2  and  7.3  and  applicable  BTPs.    No  DI&C  ISGs  were  involved,  no  safety  related  software  was  used,  and  no  complex  licensing  strategy  was  required.  

• Easy   to   Test   –   One   of   the   improvements   built   into   the   MASS   modules   is   built-­‐in   test   equipment.    All   input   modules   can   switch   to   a   TEST   mode   and   provide   an   adjustable   simulated   input   signal   for  testing.    Modules  have  test  jacks  and  LEDs  on  the  front  plate  to  make  testing  simple.      And  MASS  uses  advanced  terminal  blocks  with  both  sliding  links  and  built  in  banana  jack  connections.  

Of  course,  since  the  MASS  platform  is  designed  for  use  as  a  protection  system,  it  meets  all  the  applicable  standards,  including:  

• IEEE  279  and  603  -­‐  design  • RG  1.89  /  IEEE  323  –qualification  • IEEE  338  –  testing    • RG  1.100  /  IEEE  344  –  seismic  qualification  • IEEE  352  and  577  –  reliability  analysis    

• RG  1.53  /  IEEE  379  –  single  failure  • IEEE  383  –  cable  qualification  • RG  1.75  /  IEEE  384  –  separation    • RG  1.97  /  IEEE  497  –  PAM  • RG  1.180    –  EMI/RFI  qualification    

 

Scientech  believes   that  a  Modern  Analog  Safety  System  is   the   best   option   for   replacing   not   only   legacy   analog  systems,   but   also   for   replacing   the   digital   systems  installed   in   the   1980s   and   1990s.     These   systems   are  already  obsolete  –  they  use  microprocessors  that  are  long  out   of   production,   programed  with   instruction   sets   that  are,  by  today’s  standards,  limited  and  dis-­‐functional.    The  infrastructure   to   support   the   software   is   either  unsupported   or   non-­‐existent.     And   the   licensing   burden  associated   with   safety   related   software   is   large,  unpredictable,  costly,  and  unnecessary.    

OPTION   1:     For   those   wanting   online   monitoring   and  diagnostics,  Scientech  can  offer  a  MASS  with  a  monitoring  computer.    The  signals  required  for  online  monitoring  and  diagnostics  are  sent  from  the  safety  related  analog  system  through  1E-­‐to-­‐non-­‐1E  isolators  to  a  non-­‐safety  related  monitoring  touch-­‐screen  computer  mounted  in  one   of   the   cabinets.     The   computer   runs   a   small   version   of   Scientech’s   plant   computer   software,   R-­‐Time©

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providing   all   the   capabilities   of   a   normal   plant   process   computer   –   custom   displays,   alarm   lists,   trending,  historian,   and   so   forth.     Custom   software   is   installed   to  monitor   the   performance   of   each  module,   allowing  online  diagnostics  of  any  failure.  

OPTION   2:   An   additional   add-­‐on   for   those   preferring  Option   1   is   to   have   the  monitoring   computer   perform  semi-­‐automated  surveillance  testing.    Once  manually  connected  and   initiated,  the  computer  would  then  fully  exercise  each  module  while  continuing  to  monitor  performance.    With  the  TEST  switches  back  in  NORMAL,  the  computer  is  again  only  connected  through  the  isolators,  preventing  any  cyber  concerns.  

 

Scientech,  a  business  unit  of  Curtiss-­‐Wright  Flow  Control  Company,  is  a  global  engineering,  manufacturing  and  service   company.   Scientech   provides   nuclear   instrumentation,   power   supplies,   plant   performance   and  condition  monitoring   services,   safety   and   risk   services,   reactor   and   steam   generator   products   and   services,  licensing  and   regulatory  services  and  proprietary  database  solutions  and  software.  We  are  committed   to   the  safe  operation  and  improved  performance  and  reliability  of  power  plants  worldwide.