Hired-Hand Farm Hand Series: ST Temperature Controllers - Manual (Page 12)

4801-5043 Rev 7/00 Farm Hand ST 11
To set the Timer Percentage:
1. Depress the Mode button until the Timer Percentage LED is lit. (The Stage 1 LED will
also be lit).
2. Press the + or – buttons to set the Timer Percentage to the desired value.
Note: The Timer Percentage values change in increments of
±
5 (i.e. 5, 10, 15…).
3. The controller will return to the Room Temp. parameter after 10 seconds.
Example: If the Timer Percentage is set at 15 and the Timer Cycle is 10 minutes, then
the cooling will operate for 1 ½ minutes during the 10 min. cycle (i.e. 15% of the total
cycle). Note: Stage 1 indicator blinks while timer percentage output is active.
Example: If the Timer Percentage is set at 25 and the Timer Cycle is 5 minutes, then the
cooling will operate for 1 ¼ minutes (1 minute 15 seconds) during the cycle (i.e. 25% of
the total cycle).
11.2 Mister Stage Timer Percentage
Note: If the Mister Timer (P6) is disabled, then this setting will not be seen.
The Mister Timer can handle any of your Evaporative cooling needs. Important: The
Mister Timer does not turn on unless the temperature reaches the OnPoint of the
final cooling stage.
To set the Mister Timer Percentage:
1. Follow instructions in Section 7.2 to enable the Mister Timer. (Set P6 to ON).
2. With the Farm Hand ST in the Program Mode, press the “Mode” button to toggle to P7.
3. Press the + and – buttons to set the total cycle time (in minutes) of the Mister Timer.
This may be set from 2 minutes to 30 minutes.
4. To set the Run Time Percentage of the Mister stage, wait for the Farm Hand ST to return
to the Normal Mode.
5. With the Farm Hand ST in the Normal Mode and after setting the cycle time, toggle the
“Mode” button until the Timer Percentage LED is lit. The Stage 1 LED will also be lit to
allow changing the Timer percentage of stage 1 (See Section 8.1). Press the “Mode”
button
again to toggle to the Mister stage. (Note: If this is done correctly, the Timer Percentage
LED and the Mister Stage LED will now be lit).
6. Press the + or – button to select the % run time of the Mister Stage. Example: If the cycle
time is set to 5 minutes in step 3, and the % run time is set to 20%, then the Mister stage
will run for 1 minute during each 5 minute cycle, if the temperature is greater than the
stage’s OnPoint.
7. Setting complete.
12. Set On Points
12.1 On Point Protocols
The On Point settings determine the temperatures at which each stage turns on. The
following rules are observed when setting the On Points. The temperature controller
circuitry will automatically limit settings according to these rules, so you do not
have to remember these rules when setting On Points.
§ The On Point settings of ST Cooling Stages will always be greater than the Target
Temperature.
§ The On Point settings of all Cooling Stages increase from the Stage 1 setting.
§ The On Points of all Heat Stages will be less than the Target Temperature.
12.2 Instructions for Setting On Points
1. Press the Mode button to select stage number indicator of stage to be set.
2. Press the + and – buttons to set the On Point to the desired temperature.
3. Repeat steps 1 and 2 until all On Points have been set.
To help understand On Point settings, please read the following examples.