Configuration
Configuring The Controller
Relay Output #2
In this example Relay Output #2 is configured for “System Pump 2”.
In
Figure 26
Item #1 it indicates it has a Main Control Method of “Lag
Relay for Lead/Lag Control”. This means it is the “Lag Pump Relay”
for Lead/Lag type system pump control.
All other settings are part of the System Pump 1 configuration and will
be applied to System Pump 2 after each Changeover Interval (adjust-
able) on “System Pump 1”.
After System Pump 2 operates for its Changeover Interval (adjustable)
the sequence will change back to System Pump 1 and continuously
repeat.
Relay Output #3
In this example Relay Output #3 is configured for the “TW Spray
Pump”(Tower Spray Pump). In
Figure 27
Item #1 it indicates it has a
Main Control Method of “On Above/Off Below”. This means it will use
a setpoint that will activate the Relay Output at a Hi Limit Setpoint and
deactivate it at a Lo Limit Setpoint.
Item #2 indicates the Control Source for this relay will be the Tower
Return Water Temperature (“TW Return Water”) on AIN2. Item #3
indicates that the Hi Limit Setpoint will be 77.0° F and the Lo Limit
Setpoint will be 75.0° F.
Item #4 Shows the Enabling Relay to be the “System Active Relay”
output configured on (Relay #8). This means that in addition to the Tower
Return Water Temperature being above setpoint the “System Active”
relay must be activated for the “Tower Fan” to run.
It also has a Logical And Control Method of “Follow Active Binary
Input” as shown in Item #5. The “Binary input To Follow” is configured
as the “Request To Run” binary input (BIN1) and is shown as Item #6.
With this configuration sequence the “TW Spray Pump” (Relay #3)
will activate turning on the tower spray pump when the “Tower Return
Water Temperature” (AIN2) is above 77.0° F, the “System Active”
(Relay #8) relay output is active and the “Request To Run” (BIN1)
binary input is active.
If the “Tower Return Water Temperature” (AIN2) falls below 75.0° F,
the “System Active” relay output (Relay #8) is inactive or the “Request
to Run” (BIN1) binary input is inactive, the “TW Spray Pump” (Relay
#2) will deactivate.
27
WSHP Loop Controller
GPC-XP Guide
