such as outdoor air temperature. If no reset is required, simply enter the same values for the Control Source Hi and Lo Limit Setpoints. No Reset Source is required.
If you do need the main Control Source Setpoint to reset, this is the range over which the Reset Source must change to cause the controlling setpoint to reset from the Lo Limit to the Hi Limit values you entered. For example: you want to reset the enable/disable point for a boiler enable signal based on the changing outdoor air temperature. You would enter the Minimum outdoor air temperature that would cause the Hi Limit Setpoint to be calculated and the Maximum outdoor air temperature that would cause the Lo Limit Setpoint to be calculated.
Controlling Setpoint Deadband
You should always enter a small deadband to prevent the relay from cycling on and off continuously due to a control source reading that is toggling right around the current setpoint. The deadband you enter is added to both sides of the setpoint to create an area where the relay does not stage on or off. For example: if your setpoint was 72°F and the deadband was set for 0.5°F, the relay can change state when the temperature rises above 72.5°F or drops below 71.5°F. If you do not need unoccupied setback control, you must leave this setpoint = 0.0°F and use the High and Low setpoints to create a deadband.
Controlling Schedule
You can select one of the Internal Schedules to set the occupied or unoccupied mode of operation for the selected relay. If the relay does not require a schedule to be part of its control strategy, leave the selection at “None Selected”.
AND/OR Conditional Tests
If more than one criterion is required to make a decision, there are two other options available to aid in the decision process. An AND condition and an OR condition. If you don’t need additional tests, simply select the Not Configured option under the Control Method for each of these sources.
If you need two events to be true before the output can activate, use the AND Control Method and select a Logical AND Source.
If you want either the main Control Method OR an Alternate Control Method to activate the output, use the OR Control Method and select a Logical OR Source.
You can combine all three options to create a condition where two events must be true or a third separate event must be true to activate the output.
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