Precision Digital PD941 - Manual (Page 36)

ConsoliDator Multi-Channel Controller Instruction Manual
36
Lead-Lag Modes
(Pump Alternation Control)
Lead-Lag modes are used to
operate up to 9 relays in sequence.
This mode is commonly used for
pump alternation control. For
example: If relays #1, #2, and #3
are linked in this menu, relay #1
turns on the first time the set point is
reached and off when the reset
point is reached, relay #2 cycles the
second time, and relay #3 cycles
the third time. The sequence then
repeats beginning with relay #1.
Select [LEAD-LAG: HIGH] from
Alarm Mode options to turn relay on
when high set point is reached and
off when low reset point is reached.
Select [LEAD-LAG: LOW] from
Alarm Mode options to turn relay on
when low set point is reached and
off when high reset point is reached.
Alarm Setup: 1
Alarm Mode: LEAD-LAG: HIGH
Channel: TANK 1
High Value: 160.0 GAL
Low Value: 8.0 GAL
Delay ON: 1.0 sec
Delay OFF: 0.5 sec
Link Relays:
1 2 3 4 5 6 7 8 9
EDIT EXIT
ON:
OVER
Note: Linked relays must be set to [OFF] in their
respective menus. (i.e. If Alarm Setup 1 links Relay #2,
Alarm Setup 2 must read "Alarm Mode: [OFF]")
Channel Assign the relay to any analog or pulse input.
High Value Enter high process variable set/reset point.
Low Value Enter low process variable set/reset point.
Delay ON Enter the delay between when the set point is reached and the
relay turns on (energizes.)
Delay OFF Enter the delay between when the reset point is reached and the
relay turns off (de-energizes.)
Link Relays Select between two and nine relays to operate in sequence.