Hired-Hand Farm Hand Series: SC-5v2 - Manual (Page 19)

Part No. 4801-5324 Rev 9-05 Farm Hand SC-5v2 5 Stage 19 of 40
Tunneling on outside temperature in a power ventilated building
The controller reacts in the same way as in the naturally ventilated building. For
proper operation in a house without a curtain sidewall, you must jumper the
curtain closed switches on the main curtain together.
Tunneling on a stage in a power ventilated building
As soon as the lowest programmed Cool Tunnel stage comes on, the controller
opens the inlet curtain and leaves all Cool Negative Tunnel and Cool Tunnel
stages on. When the temperature begins to fall and the lowest programmed Cool
Tunnel stage turns off, the controller will close the inlet fully and return the
stages to normal operation immediately.
Note: If you are using a main sidewall curtain, it must run at a speed where it
can go from fully open to fully closed in less than 13 minutes.
Otherwise, the controller will not operate tunnel properly.
9.3 Cool Timer Stage Operation
All stages of the SC-5v2 can be programmed as cool timer stages. A cool timer stage will come
on and run at the timer percentage whenever temperature is above it’s off point, and its timer
percentage will increase as temperature rises. The following graph shows how you can vary this
percentage.
Minimum On Point
Minimum Time
Maximum On Point
Maximum Time
Temperature (F)
Percent of
Timer Duration
(%)
40
100
75 78 81
70
The above graph shows how the timer percentage of the fan will increase with the following
settings:
Setting Parameter Setpoint
Sensors P1 - Stage Sensors Any Combination
Timer Setting P3 - Timer Selection 2 - Cool Timer
Maximum On Point P4 - On Point 81
°F
Minimum On Point P5 - Off Point 75
°F
Minimum Percentage Minimum Runtime Percent 40%
From the graph, you can see that at 78
°F, the cool timer stage will run at 70% of the timer
duration. Below 75
°F the stage will never run. Above 81°F the cool timer stage will run at 100%
continuously.
The minimum Runtime Percentage may be set when going through the main display indicators.