6. The configured LAG STA RT TIMER entry has elapsed. The LAG START TIMER shall be
started when the lead chi ller ramp loading is com pl eted. The LAG START TIME R ent ry is
accessed by select ing Lead/Lag from the Equipm en t Configuration tab le of the Service
menu.
When all of the above requi rements have been met, t he la g chiller is forced to a STAR T
mode. The PIC control t hen monitors the lag chiller for a successful start. If the lag chille r fails to
start, the standby chill er, if configured, is star t ed.
Lag Chiller Shutdown Requirements
The following condit ion s must be met in order for the lag c hi ller to be stopped.
1. Lead chiller COMPRESSOR MOTOR LOAD value is less than the lead chiller percent
capacity plus 15%.
Note: Lead chiller percent capacity = 100 – LAG PERCENT CAPACITY
The LAG PERCENT CAPACITY value is configured on the Lead/Lag Configuration screen.
2. The lead chiller chilled water temper ature is less tha n the CONTROL POIN T plus 1/2 of the
WATER/BRINE DEADBAND.
3. The configured LAG STO P TIMER entry has elapse d. The LAG STOP TIMER is start ed
when the CHILLED WATER TEMPERATURE is less than the CHILLED WATER
CONTROL POINT plus 1/ 2 of the WATER/BRINE DEADB A ND and the lead chiller