Omega WI8XX-U - Manual (Page 45)

4.3.7.2 Setpoints & On/Off Control
Auto Setpoint Deviation: If "enabled", allows changes to Setpoint 1 to be
made automatically to Setpoint 2. This mode is very helpful if the Temperature
changes often.
In Setpoint Deviation Mode, set SP2 a certain number of degrees or counts
away from SP1--this relation remains fixed when SP1 is changed.
For instance:
Setting SP1=200 and SP2=20 and enabling SP Deviation means that the
absolute value of SP2=220.
Moving SP1 to 300, the absolute value of SP2 becomes 320.
Setpoint 1: This setpoint controls Output 1
Setpoint 2: This setpoint controls Output 2
Permanent Store: Check to save Setpoints in the Meter’s permanent storage.
On/Off 1 and On/Off 2: To enable and disable On/Off Control.
Enabling On/Off Controls will disable the Alarms, and vice versa.
DeadBand: The Dead Band or neutral zone, is the number of degrees counts
around Setpoint 1 (or Setpoint 2 if On/Off 2) which the temperature value must
pass above or below the Setpoint before the output changes state.
Action: Choice of direct or reverse. The error that results from the
measurement of the Process Variable may be positive or negative since it may
be greater or smaller than the Setpoint.
If a positive error should cause the Meter output to increase (i.e. cooling), it
would be called Direct Acting.
If a negative error should cause the output to increase (i.e. heating), it would be
called Reverse Acting.
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