iSMA-B-MINI/MIX BACnet User Manual
www.ismacontrolli.com
DMP261en | 1st Issue rev. 8 | 05/2022
page 60 of 114
Figure 40. The heating mode algorithm
Cooling Mode (4U4O-H and 4U4O-H-IP Only)
In this mode, the output is controlled like a typical thermostat, based on the Setpoint
object and Control value (Input signal) with a differential parameter defined in the
Differential object.
The output signal works in 2 states - low and high.
If the Control value is less than or equals to the difference between the Setpoint object
and Differential object, the output is in the low state.
If the Control value is greater than or equals to the sum of the Setpoint object and
Differential object, the output is in the high state.
The output in the low state:
Control value <= Setpoint
–
Differential
The output in the high state:
Control value >= Se Differential
The cooling mode algorithm is shown in the chart below:
WARNING!
In case if the temperature sensor fails (if it is disconnected or shorted), the heating
mode does not work, and the output remains in the false state.
