TELEDYNE OLDHAM SIMTRONICS Everywhereyoulook BM 25A, Руководство пользователя

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BM 25A/AW
AREA GAS MONITOR
USER MANUAL
6 NPB25AEN
Revision D.0
1.4.4 Dry logic inputs (yellow ring)
•
Pin 2: logic input for alarm transfer
•
Pin 5: logic input for alarm acknowledgement
•
Pin 7: common ground
Unused connectors must be equipped with their
protective cap.
See details on pages 12 and 41.
Figure 7: dry logic inputs
1.4.5 Intrinsic safety parameters
•
Alarm relay output: dry relay contact, Ui = 30 V, Ii = 150 mA, no L or C condition
•
Power supply for trickle charging: Ui = 30 V, Ii = 160 mA, no L or C condition
•
Dry logic input: Uo = 5 V, Io = 50 mA, Lo = 8 mH, Co = 7 µF
The person responsible for the gas monitor must create a Descriptive System
Document (for intrinsically safe circuits).
1.5 Gas sensors
The sensors are located on the front of the monitor (Figure 2, ref. 10). They are smart, pre-
calibrated from factory and interchangeable. They are composed of a sensitive element and
electrical components, including an EEPROM memory in which the sensor characteristics are
stored (gas type, range, span value, instantaneous, STEL and TWA alarm values, date of
manufacture, serial number, date of last calibration, span reserve, etc.). The span reserve is
updated after each calibration and allows the user to gage the optimal time for changing the
sensor. Sensors must be positioned as indicated in the table above.
Figure 8: sensors configuration