Maintenance
Reference Manual
June 2016
MAN-0076, Revision 09
36
Maintenance
Section 7:
Maintenance
7.1
Periodic response check
Net Safety Monitoring recommends that a bump test be performed every 90 days to ensure continued
functionality and accuracy of the detection system. Full calibration is recommended when the sensor
fails to meet acceptable accuracy standards. This involves the application of calibration gas to the
sensor, then the observation of the response LEDs, analog output, and external monitoring equipment.
Be sure to prevent unwanted response of external monitoring devices and equipment during this
procedure. If the Millennium II’s response to calibration gas is within the specified accuracy then it is
not necessary to perform a calibration.
Example: When 50% of full scale is applied, the response is expected to be between 11.5 mA (47% of full
scale) and 12.5 mA (53% of full scale). An additional consideration is the accuracy tolerance of the
calibration gas which may be + or - a few percent. If the calibration gas is + or - 10% of full scale then the
reading may be from 10.7 mA (42% of full scale) to 13.3 mA (58% of full scale).
7.2
Troubleshooting
Response to the input should be checked and, if necessary, calibration should be performed whenever
the accuracy of this check is not satisfactory. The system should also be checked when sensor or
transmitter is added or removed. If problems should develop, first check for faulty wiring, confirm
proper voltage to transmitter and attempt a calibration. If problems persist, please contact Net
Safety’s Service Department first by phone to try and resolve any issues. If issues cannot be resolved,
please follow the procedure on ‘how to return equipment’.
7.3
Storage
The transmitter and its electronic components/parts should be stored in locations free from dust and
moisture. The storage temperature should be well within the limits of the certified temperatures of the
equipment. See
Section 10
for storage temperatures.