Hired-Hand ICS-500 Environmental Controller - Manual (Page 21)

Integrated Control System 500 19
7.2. Stage Operation
Stages may be operated by the controller automatically, by the controller on the timer, or
manually by turning the switches on the contactor panel.
7.2.1. Manual
To turn a particular stage on, flip its toggle switch to the “ON” position. The red
indicator light should turn on. If you wish to prevent a stage from operating, flip the
switch to the “OFF” position. (Note: The back-up board may still turn the stage on if a
back-up condition exists.)
To return the stage to operation by the controller, flip the switch to the “AUTO”
position.
7.2.2. Automatic
The controller may turn a stage on for two different reasons. First, if a stage is on the
timer, the timer will turn it on from time to time according to it’s settings. Second, if the
temperature inside the building reaches the level required by that particular stage’s
program.
The controller uses an offset/differential method for determining if a stage should be
turned on or off. This method is explained below
• Offset:
The point above (cool) or below (heat) target temperature where the stage turns
off.
• Differential:
The difference in degrees between the temperature a stage comes on and the
temperature the stage goes off.
Examples
Heat Mode:
If the Target Temp is set at 80 degrees, Offset set at 4 degrees, and Differential set at 2
degrees, The System will engage Heat Mode when building temperature reaches 74
degrees and the curtains are closed.
Target Temp - Offset - Differential = Heat Mode on
80 - 4 - 2 = 74
If the Target Temp is set at 80 degrees, Offset at 4 degrees and Differential set at 2
degrees, The System will disengage Heat Mode when building temperature reaches 76
degrees.
Target Temp - Offset = Heat Mode Off
80 - 4 = 76
Cool Mode:
If the Target Temp is set at 80 degrees, Offset set at 5 degrees, and Differential set at 2
degrees, The System will engage the fans when building temperature reaches 87
degrees.
Target Temp + Offset + Differential = Cool Mode On