Dräger Polytron 7000, Инструкция по эксплуатации

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Device settings
2. Make the settings. Use Next to call up the steps in turn.
a. Set the value for the alarm threshold.
Min./max. Alarm thresholds are dependent on the sensor.
Alarm thresholds for O
2
sensors can be set anywhere between 0.1 vol% and
25 vol%.
b. Set the alarm direction.
c. Set the latch mode.
If the gas detector is used to detect oxygen, Alarm A1 and Alarm A2 must be
configured as latching. If both alarm thresholds have the same direction
(activation when the oxygen concentration is increasing or decreasing), the
first alarm may be configured as
Non Latching .
d. Set the alarm acknowledge mode. For safety-relevant switching actions,
configure the alarm as Non Acknowledging .
e. Set the hysteresis value.
This feature prevents the relay from being energised and deenergised in
rapid sequence.
Example: The alarm threshold was set to 40 ppm and the hysteresis to
3 ppm. The alarm remains active until the measured value has fallen below
37 ppm.
f. At the overview of the settings made, select Confirm .
9.2.5 Switching alarm acknowledgement on or off at the gas detector
Enables/disables the possibility to acknowledge alarms at the gas detector by
pressing .
When this function is switched off and the alarm is configured as latching, an alarm
can only be acknowledged by a voltage interruption to the gas detector.
1. Select
Settings > Instrument > Alarm > Acknowledge mode .
2. Select Enable or Disable .
Rising An alarm is issued if the measured value is above the
alarm threshold.
Falling An alarm is issued if the measured value is below the
alarm threshold.
Latching Alarm relays do not change their state automatically
when the alarm condition ceases. Alarm must be
acknowledged manually.
Non Latching Alarm relays change their state when the alarm condi-
tion ceases. Alarm does not need to be acknowledged
manually. The gas detector is no longer in alarm state.
Acknowledging Alarm relays can be acknowledged although an alarm
is active.
Non Acknowledg-
ing Alarm relays can only be acknowledged when the
alarm is no longer active.
OK