Over Range; Under Range - Dräger REGARD 39 0 Series Instructions For Use Manual

2. Press Hold / II / ▲ again for less than 1 second to unfreeze the display screen
(restart scrolling).
6.1.2 Gas type or measuring range
The display screen can toggle between the gas type and the measuring range. By
default, the gas type is shown.
● Press Hold / II / ▲ for longer than 1 second to display the full scale.
6.1.3

Over range

If the gas value rises above the measuring range (the transmitter signal rises above
20 mA), Over-range is displayed. The over range reading is latching (i.e. it remains
on the display even if the gas value falls back into the measuring range).
● Press Acknowledge/OK (or if available, carry out a remote acknowledgement),
in order to reset the display. If the button is pressed while the gas value is above
the measurement range, the display will be reset as soon as the gas value falls
back into the measuring range.
6.1.4

Under range

If the gas value falls under the measuring range (the transmitter signal drops below
3.8 mA - but this is not a maintenance or fault signal), Under-range is displayed.
6.1.5 Maintenance
If the transmitter needs to be serviced (the transmitter emits a maintenance signal),
Maintenance is displayed.
6.2 Alarm, fault and activity LEDs
The alarm thresholds and activation modes are adapted to the requirements of the
user. The actions and measures to be taken upon activation of an alarm or fault
LED must be specified by the person responsible for the gas detection system.
Although there are up to three gas alarms (A1 to A3) and two fault alarms (F1 and
F2), the control unit has no LEDs for alarm A3 and fault F2. External warning units
can be configured to display alarm A3 and fault F2.
LED
Alarm A1
Alarm A2
Fault F1
REGARD
Condition
Flashes A1 alarm triggered
Lights up A1 alarm acknowledged, however alarm state pres-
Off ent
No alarm state
Flashes A2 alarm triggered
Lights up A2 alarm acknowledged, however alarm state pres-
Off ent
No alarm state
Flashes F1 alarm triggered
Lights up F1 alarm acknowledged, however fault present
Off Channel fault-free
®
3900
Operation