Schweitzer Engineering Laboratories SEL-167D Instruction Manual Download

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INSTALLATION CHECKOUT

The following suggestions may be used or combined with your normal practice. In no case
should a recommendation be followed unless it is allowed by the rules of your normal
practice.

A  portable  terminal  or  computer  is  a  convenient  tool  for  providing  local  communications  with
the  SEL-267D  relay  during  checkout  in  the  field.  Such  a  device  should  be  connected  to
PORT  2R  or  PORT  2F  for  checkout  (with  PORT  2  being  designated  as  the  automatic  port
using  the  AUTO  setting  in  the  SET  command).

Apply  control  power  and  make  sure  the  terminal  displays  the  startup  message.  If  not,  set
AUTO  =  2,  using  the  SET  command  on  Access  Level  2.  Check  the  settings  with  the
ACCESS  and  SHOWSET  commands.  Use  the  TIME  and  DATE  commands  to  set  the
clock  and  date.

Apply  three-phase  voltages.  Execute  the  METER  command  and  verify  that  the  readings
are  accurate.  If  not,  be  sure  the  correct  PT  ratio  was  entered  and  recall  that  displayed
values  are  in  primary  line-to-neutral  and  line-to-line  kV.

Use the TRIGGER command to save an event record. Type the EVENT 1 command
and examine the triggered event record. Referring to the top row of data as the

components and the next row as the

components, plot the three voltage phasors to

ensure  that  they  are  120  degrees  apart,  of  reasonable  magnitudes,  and  rotating  in  the
positive-sequence  direction.  The  zero-sequence  voltage  Y  and  X  components  (times  a
factor  of  three)  are  the  total  of  the  three  Y  components  and  the  total  of  the  three  X
components.  These  sums  should  be  near  zero  if  balanced  three-phase  potentials  are
present.

Use  the  TARGET  command  to  check  the  state  of  all  contact  inputs  and  outputs.  For
example,  if  the  connections  to  the  circuit  breaker  52A  contact  are  made  when  the  circuit
breaker  is  closed,  the  TARGET  command  with  option  5  should  show  a  one  (1)  under  the
52A  heading  (type  TARGET  5  <ENTER>).

Proceed  to  Access  Level  2  with  the  2ACCESS  command  and  appropriate  password.  Be
sure  that  the  ALARM  relay  contacts  close  and  open  when  the  2ACCESS  command  is
executed  (The  ALARM  pulse  will  not  be  detectable  if  the  ALARM  contacts  are  perma-
nently  asserted  due  to  any  other  alarm  condition).

The  tripping  function  may  be  tested  in  any  of  three  ways.  First,  be  sure  the  circuit
breaker  can  be  tripped  by  the  SEL-267D  relay  when  you  execute  the  OPEN  command.
Be  sure  the  TC  bit  is  set  in  the  MTU  mask.  Second,  the  circuit  breaker  should  trip  when
you  assert  the  DIRECT  TRIP  input,  assuming  that  the  DT  bit  is  selected  in  the  MTU
mask.  The  TRIP  output  relay  opens  in  both  of  these  cases  after  the  52A  input  is
deasserted,  indicating  that  the  circuit  breaker  has  indeed  opened.  This  function  of
monitoring  the  52A  contact  ensures  that  the  output  relay  does  not  inadvertently  open
while  trip  coil  current  is  flowing  in  response  to  a  control  operation.  Third,  the  circuit
breaker  should  trip  when  you  apply  voltages  and  currents  representing  a  fault  condition

5-6

Installation

SEL-267D Instruction Manual

Date Code 920326