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Deviation LO
Deviation LO adjusts the alarm value as the SP temperature value is adjusted.
Whatever value deviation LO is set at, it will remain the same until changed.
Refer to Figure 22.
ALARM MODE
DEVIATION LO
FIGURE 22. DEVIATION LO SCREEN
For example: if the Deviation LO value is set for 10 degrees Fahrenheit and
the SP temperature is set for 50 degrees Fahrenheit, the alarm will trigger at
40 degrees Fahrenheit. If the SP temperature value is changed to 45 degrees
Fahrenheit, the Deviation LO will trigger the alarm at 35 degrees Fahrenheit.
If the Control Action is set to HEAT and the alarm condition exists when the
RUN key is pressed, the alarm will not be activated. The PV temperature
must first rise above the alarm setpoint before the alarm is enabled. This
allows for normal system startup without activating the alarm.
Select the DEVIATION - LO screen by pressing the MENU key. The following
screen will appear (refer to Figure 23). Move the cursor to the left using the
LEFT arrow key. When the setting is correct, press the MENU key to enter
that setting and to move the program to the alarm hysteresis screen.
DEVIATION ALARM
LO XXXXX °F
FIGURE 23. DEVIATION LO SETTINGS SCREEN
Deviation HI
Deviation HI will adjust the alarm value as the SP temperature value is ad-
justed. Whatever value Deviation HI is set at, it will remain the same until
changed. Refer to Figure 24.
ALARM MODE
DEVIATION HI
FIGURE 24. DEVIATION HI SCREEN
