General Monitors S800, Инструкция по эксплуатации

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Model S800
9
System power “ON” Test
Ensure that all mining machine switches for main power, pumps, cutting heads,
headlights, loading arms, etc. are “OFF”
Energize mining machine cable main power and note the following.
During a 20 second start-up, the digital display will show an increasing, then
decreasing gas level as the sensor warms up and stabilizes. At the end of the 20
second start-up, the display may still indicate an elevated sensor level that will
decrease to the present gas level. Additionally, the
READY LED will light indicating
system readiness.
If the indicated gas level exceeds the Alarm or Warn set-points during start-up, the
relays will not activate and the LED’s will remain off. However, if the gas level is still
elevated after the system has stabilized, the appropriate relay will be activated and the
LED will light.
The level the sensor ramps to during stabilization is directly related to how cool the
sensor has become. The length of time off power and ambient temperature are
contributing factors.
3.7 Sensor Locations
The sensor should be mounted as close as practical to the miner cutting head. For
longwall, one at the head gate and one at the tail gate. These are the recommended
locations for Methane detection.
In addition, there are certain considerations to be taken into account when locating
sensors. The optimum sensor location is different for each application; and, therefore,
the customer must evaluate conditions at the sensor site in order to make the proper
determination.
Generally:
•
The sensor should be easily accessible for calibration checks. Ensure that sufficient
clearance exists to allow the use of field calibration devices.
•
The sensor head should always be pointing down and out of the direct blast of
water spray to prevent water build up on the sensing element.
•
The sensor should not be placed where it may be coated by contaminating
substances.