Hired-Hand System 500 Power Curtain Controller - Manual (Page 13)

System 500™ Power Curtain™ Controller 11
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. Mode
The mode of each stage tells the controller whether it should act to correct a low or high
temperature. There are five modes available for use with this controller. Below is a list
with a short description of each:
Heat: Stage used to raise temperature. (Heaters, Brooders, etc.)
Cool Negative: A stage only operable when the curtains are closed.
Cool Negative/Tunnel: This stage may operate when the curtains are closed, or
whenever the controller has gone into tunnel mode (via the OSC mechanism).
Cool Tunnel: This stage is only operable when the controller has gone into tunnel
mode.
Cool Stir: This stage is operable at any time except when in tunnel mode.
7.2.2. Manual
To turn a particular stage on, flip its toggle switch on the contactor panel 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.
7.2.3. 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