BULLETIN I-680
3-2-99
2
1.22 Proportional Output Wiring
See the 4.0 Specification Section (Page 3)
for minimum/maximum loads for the
proportional outputs. The wiring of the
proportional output signals is done by
lifting the white lever, inserting the signal
wire and pressing the white lever flat. Use
copper conductors only, rated for a
minimum of 250 volts, with a minimum
wire size of 26 AWG (22 AWG
maximum). Figure #3, Proportional
Output Wiring shows the wiring to a
remote Brasch Gas Detector Control
Panel, DDCS or BMS.
2.0 Unit Operation
When power is applied to the Nitrogen Dioxide Gas Transmitter the internal green power LED will
illuminate. This LED will stay ON as long as power is supplied to the transmitter. If the power ON
LED should go out, see the 5.0 Troubleshooting Section (Page 4) for help.
This Nitrogen Dioxide Gas Transmitter has one mode of operation, Normal. Upon the application of
power the unit will enter the Normal mode.
In the Normal mode the transmitter monitors the concentration of nitrogen dioxide (NO
2
) and generates
the proportional output signal.
3.0 Operational Settings
3.1 PROPORTIONAL OUTPUT OPTIONS
The gas transmitter has four different proportional output options that are selectable on the transmitter
board. The four options are 4 – 20 maDC current loop, 0 – 1 VDC voltage output, 0 – 5 VDC voltage
output and 0 – 10 VDC voltage output. The 4 – 20 maDC current loop is used with the Brasch Gas
Detector Control Panel. Any of the four options can be connected to a Direct Digital Control System
(DDCS) or Building Management System (BMS). See 4.0 the Specification Section (Page 3) for the
input impedance for each of the proportional outputs.
Figure #3 Proportional Output Wiring
Figure #2 Input Power Wiring
