User guide
TS 870 TRANSFER SWITCH 
PM062 REV 5 08/05/05  8  Thomson Technology 
4.2.  TYPICAL COMMISSIONING PROCEDURES 
CAUTION: 
Commissioning procedures must be performed by qualified 
personnel  only.    Ensure  the  Automatic  Transfer  Switch 
(ATS) Control Circuit Isolation Plug is disconnected prior to 
energizing the supply sources.  Manually place the transfer 
switch  mechanism  in  the  neutral  position  prior  to  applying 
power. Failure  to  do  so  may  result  in  equipment failure or 
personal injury. 
Note:  The  TYPICAL  AUTOMATIC  TRANSFER  SWITCH  COMMISSIONING 
PROCEDURES MODEL SERIES TS 870 (attached as “Appendix A ”) is provided for 
general  information  only  pertaining  to  typical  site  installations  and  applications.    Contact 
Thomson Technology for further information as may be required. 
Note: An optional hand held, plug-in Service Display Module (SDM) is available for the TSC 
80  Transfer  Controller.    The  SDM  module  provides  an  LCD  screen  to  display  additional 
detailed  information  on  the  operation  and  settings  of  the  TSC  80  controller  for  simplified 
servicing/trouble  shooting  procedures.  For  detailed  information,  refer  to  the  separate  SDM 
module instruction manual (PM065). 
5.  GENERAL THEORY OF OPERATION 
5.1.  STANDARD AUTOMATIC TRANSFER SWITCH 
5.1.1.  NORMAL OPERATION 
When utility supply voltage drops below a preset nominal value (adjustable from 70% 
to 100%  of  nominal) on any phase, an  engine start  delay circuit is initiated and the 
transfer  to utility  supply  signal  will  be removed  (i.e.  contact  opening).    Following 
expiry of the engine start delay period (adjustable from 0 to 60 sec.) an engine start 
signal (contact closure) will be given. 
Once the engine starts, the transfer  switch controller will monitor the generator 
voltage and frequency levels. Once the generator voltage and frequency rises above 
preset  values (adjustable  from  70%  to  95%  of  nominal),  the  engine  warm-up  timer 










