Setra System SRCM - Manual (Page 14)

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If selecting Analog Ch1 or Analog Ch2 for
either Primary of Secondary Room, enter
full-scale (FS) range that matches the trans-
ducer being used
Also enter voltage or milliampere range
that matches the transducer being used
Select desired units of measure to display on the Home
screen, either “WC or Pa. The unit of measure for the exter-
nal transducer must be selected before entering range and
output of the unit. After entering all data the units may be
changed and the range will scale accordingly.
The SRCM has 2 Analog Input Channels (ADC-CH1 and ADC-CH2)
Note: If a 4-20 mA transmitter is used as an analog input then a 250 ohm resistor
must be field installed and this will be translated into a 1-5 VDC input at the input
terminals.
This takes an analog input from any transducer or transmitter: pressure, temperature
or humidity. If an external transducer is used, the full scale values and parameters
need to be configured into the SRCM so the unit understands the scale of measure-
ment being received on inputs ADC CH-1 or ADC CH-2.
The following is an example using a pressure transducer to measure secondary room
pressures. This is showing a pressure transducer with a range of ±1"WC and output
of 4-20 mA over that range.
The following is an example using a temperature sensor to measure primary room
temperature. This is showing a temperature range of ±50°C and output of 1-10 VDC
over that range.
The following is an example using a humidity sensor to measure primary room rela-
Analog Inputs