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9
Installtion of a semi-bridge converters
(on Dräger RailGard-W1 and -W4 only)
The catalytic sensor in the Polytron SE Ex forms one half of a Wheatstone bridge
while the converter board has to provide the second half of this bridge.
Therefore it is necesarry to use a semi-bridge converter (Part No. SC00016), if one
or more Polytron SE Ex sensing heads are connected to a Dräger RailGard-W1 or -
W4.
Thus the converter powers the sensor and converts the semi-bridge signal into
a 4 to 20 mA signal, suitable for internal processing within the Dräger RailGard.
Procedure:
Switch off the supply voltage.
Remove the short-circuit strap and insert the converter.
Install the converter fastening before closing the case.