Application

Sequence of Operation
Room Unit Identification
30
Siemens Industry, Inc.
Application Note, App 2928
140-1302
2015-07-07
CTL TEMP = ROOM TEMP + TEMP OFFSET
Example
If the actual room temperature is 72.0°F, and the value of ROOM TEMP is 73.0°F, then
the value entered into TEMP OFFSET is
-1.0. In this case, the value of ROOM TEMP
would read 73.0°F, but the value of CTL TEMP would read 72.0°F.
Room Unit Identification
 For Analog Room Units (Series 1000) – The revision number is visually identified
by its case.
 For Digital Room Units (Series 200/2300 Firmware Revision 25 or earlier) – The
revision number displays for 5 seconds when the room unit is first powered up.
These room units will display laptop when a laptop is connected and will no
longer update room temperature sensor values.
 For Digital Room Units (Series 2200/2300 Firmware Revision 26 and later) – The
revision number displays for 5 seconds when the room unit is first powered up or
when a laptop is disconnected. These room units will continue to display and
update the room temperature sensor values when a laptop is connected.
Room Unit Operation
Sensor Select
SENSOR SEL is a configurable, enumerated point (values are additive). This point tells
the controller what type of room unit is being used and how to handle loss of
communication, for more information see Fail Mode Operation [➙ 39]. It also provides
the ability to enable the optional RH and CO2 sensors and indicates which thermistor
type is connected.
Room Temperature, Setpoint, RH and CO2
 When the digital room unit (Series 2200/2300) is used, SENSOR SEL selects the
source for temperature and setpoint and enables a loss of communications
indication:
– 1 = enables supervision (from the room unit) for fail communications for
temperature and setpoint.
– 2 = enables supervision (from the room unit) for fail communications for relative
humidity.
– 4 = enables supervision (from the room unit) for fail communications for CO2.
 When the analog room unit (Series 1000/2000) is used, SENSOR SEL values for
temperature/setpoint, relative humidity and CO2 should be left at their default
values (0).
Thermistor Inputs
 Default for input is 10K.
 To enable 100K Ω thermistor on input, see the following table for additive values.