Oldham MX 52, Installation Manual

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- European Standard EN 50271
Oxygen detectors:
- European Standard EN 50104 where the device is used with OLCT 20, 40, 50 and
60 gas detectors. Where the device is used with other types of sensor producing an
output measurement current of 4/20 mA, they must comply with paragraph 1.5 of
Appendix II of the ATEX 94/9/EC Directive and be compatible with their
characteristics (cf. device transfer curve).
- European Standard EN 50271
5.3. CONNECTING DETECTORS OTHER THAN OLDHAM DETECTORS
TO THE MX52 DEVICE
As previously explained, users wishing to connect detectors other than those
manufactured by OLDHAM, must ensure their compatibility with the device in order that the
resulting combination may be considered as a safety device.
5.3.1. Device transfer curves in 0% to 100% LEL configuration
The following curve shows the response of the device in terms of value measured, and
fault processing as a function of the input current value supplied by the detector. Where the
user connects a brand of detector other than OLDHAM to the MX52 device, he must check
carefully that the transfer curve is fully compatible with the device input characteristics, to
ensure that the data generated by the detector is correctly interpreted. Equally, the device must
supply a suitable power supply voltage, allowing for cable voltage losses.
4
mA 20
mA
100% LEL
Signal supplied by
the detector in mA
Display
in % LEL
Fault
Fault
1.2
mA
0% LEL
-17.5% LE L
SUP