Technical Manual
|
Dräger Polytron
®
8000 Series
69
Instrument settings
e. Set the hysteresis mode.
The hysteresis function defines an interval where a triggered relay maintains
its status until the gas concentration is outside the defined interval. Example:
Alarm threshold is set to 40 ppm and hysteresis to 3 ppm The alarm stays
active until the value falls below 37 ppm. This prevents relays from chattering
at an alarm threshold.
A confirmation screen shows all settings.
f. Select
Confirm
and confirm with OK.
✓
The new settings are saved.
12.11 Testing
alarms/relays
These functions change the status of a relay and LED for test purposes (e.g. to
check the function of alarm devices connected to the relay) and the symbol is
displayed. After exiting this function, the status of the relay and LED will
automatically return to their previous status.
1. Select
Settings
>
Instrument
>
Alarm
the desired alarm condition and confirm.
2. Select
Enable
or
Disable
and confirm.
✓
If the function is activated, the fault relay is de-energized and the 4 to 20 mA
interface is set to the fault current. The yellow LED is lit, the symbol for
maintenance is shown.
Set Alarm A1
Simulates pre-alarm
Set alarm A2
Simulates main alarm
Set fault
Simulates fault signal
Содержание Polytron 8000 Series
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