Specifications

Setting Room Temperature Setpoints
9
Siemens Industry, Inc.
140-0893 Start-up
Draft
1/12/2010
Setting Room Temperature Setpoints
 Day (or occupied) cooling setpoint: DAY CLG STPT
 Day (or occupied) heating setpoint: DAY HTG STPT
 Night (or unoccupied) cooling setpoint: NGT CLG STPT
 Night (or unoccupied) heating setpoint: NGT HTG STPT
1. If the room temperature sensor has a setpoint dial that will be used, set STPT DIAL
to
YES. Otherwise, set STPT DIAL to NO.
− Set RM STPT MIN and RM STPT MAX for the minimum and maximum
allowable room temperature setpoint values, respectively. Valid values range
from 55° to 95°F (13° to 35°C). Default values are 55°F (13°C) for RM STPT
MIN and 90°F (32°C) for RM STPT MAX.
2. Setpoint dial configured with a heating/cooling deadband (default).
− To allow the controller to operate with a heating/cooling deadband (functioning
the same as provided when the setpoint dial is not present) the following
configuration should be used.
− Set the DAY HTG STPT less than the DAY CLG STPT by the deadband (or
zero energy band) that is desired. (for example, DAY HTG STPT = 70°F; DAY
CLG STPT = 74°F, providing a deadband of 4 degrees). Only the difference
between these values is used to determine the setpoint that will be used.
− As described below, the setpoint(s) for heating/cooling will be 1/2 of the
deadband above or below the setpoint dial value.
 When HEAT.COOL equals HEAT, then:
 CTL STPT will equal RM STPT DIAL – 0.5 * (DAY CLG STPT – DAY HTG
STPT) and will be limited by RM STPT MIN and RM STPT MAX.
 When HEAT.COOL equals COOL, then:
 CTL STPT will equal RM STPT DIAL + 0.5 * (DAY CLG STPT – DAY HTG
STPT) and will be limited by RM STPT MIN and RM STPT MAX.
NOTE: A space where the deadband is used can be more energy efficient than
a space where the deadband is not being used
3. Setpoint dial configured for zero heating/cooling deadband.
− When the job specification requires a common heating and cooling temperature
setpoint, the following configuration should be used.
− Set DAY HTG STPT equal to DAY CLG STPT. This will configure the setpoint
deadband equal to zero.
− In addition, when a setpoint deadband equals zero, then:
− CTL STPT will equal RM STPT DIAL, and will be limited by RM STPT MIN and
RM STPT MAX.
NOTE: A space where the heating/cooling deadband is zero may be more