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Figure 42. External Setp Point Example
8.D.9.a External – Remote Set Point
External (0 – 10VDC or 4 – 20mA)
•
An External heat demand can be initiated by a Building Automation System (BAS) using a 0-10VDC or 4-20mA
signal. This input can be configured for Remote Set Point or Remote Firing Rate operations.
•
With Remote Set Point selected, the unit will initiate a heat demand once the analog input signal exceeds the
Demand On value. Once the demand is initiated, the analog input signal must be lower than Demand Off to
remove the heat demand. With an active demand, the unit will locate the set point according to the analog input
signal.
•
Using the default values for Boiler Max Set Point (180°F), Boiler Min Set Point (140°F), Demand Minimum
(2.5VDC), Demand Maximum (10.0VDC), the unit will linearize the set point, as shown in
Figure 42
.
C O N F I G U R AT I O N