Dräger Polytron 8900 UGLD Instructions For Use Manual page 19

Acknowledge- Alarm relay and LED can be reset before
able
alarm condition clears.
Non-acknowl- Alarm relay and LED can not be reset until
edgeable the alarm condition clears.
Pre-Acknowl- Alarm status is acknowledgeable before the
edgeable alarm condition clears. However, the alarm
relay and LED stay active until the alarm
condition clears.
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 75 dB and hysteresis to 3 dB.
The alarm stays active until the value falls below
72 dB. This prevents relays from chattering at an alarm
threshold.
When the direction of an alarm was changed (from
falling to rising or vice versa), the value of the
hysteresis must be checked and corrected again if
necessary.
 A confirmation screen shows all settings.
f. Select Confirm and confirm with OK.
✓ The new settings are saved.
10.1.4 Adjusting alarm delay time and analyzed
time
The alarm delay time is per default set to 30 seconds and can
be adjusted between 1 second and the analyzed time.
The analyzed time is per default set to 60 seconds and can
be adjusted by DrägerService only between 1 second and
240 seconds.
1. Select Settings > Sensor > UGLD delay > Delay and
confirm.
2. Enter new alarm delay time in seconds and confirm with
OK.
3. Select Confirm and confirm with OK.
✓ The new alarm delay time is saved.
10.1.5 Activating delay function
The delay function can be individually activated for the
display, the alarm relays and the 4-20 mA output signal.
1. Select Settings > Sensor > UGLD delay and confirm.
2. Select desired output and confirm: Display, Alarm
Relays and 4-20 mA.
3. Select Enable or Disable for each output and confirm with
Back to menu.
✓ The delay function is activated for the selected output(s).
10.1.6 Setting analog output signal (4-20 mA)
characteristic
1. Select Settings > Communication > Analog interface >
UGLD signals and confirm.
2. Select analog output signal characteristic and confirm:
Instructions for use |
Dräger Polytron
®
8900 UGLD Firmware version ≥ 4.0.x
Alarm normal The 4-20 mA reacts proportional to the
detected ultrasonic signal.
Alarm The 4-20 mA reacts proportional to the
enhanced detected ultrasonic signal until an alarm is
reached. The signal then jumps to 16 mA if
A1 is triggered and to 20 mA if A2 is trig-
gered.
Alarm only The analog output signal stays at 4 mA until
an alarm is reached. The signal then jumps
to 16 mA if A1 is triggered and to 20 mA if
A2 is triggered.
3. Select Back to menu and confirm.
✓ The new settings are saved.
10.2 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
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.
Set Alarm A1 Simulates pre-alarm
Set alarm A2 Simulates main alarm
Set fault Simulates fault signal
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.
10.3 Setting passwords
1. Select Settings > Instrument > Passwords the desired
password and confirm.
Calibration Access to zero and span calibration
PWD
Settings PWD Access to all configuration parameters
2. Select the line for editing the password and confirm.
3. Set the password and confirm.
4. Select Confirm and confirm with [OK].
10.4 Setting date and time
1. Select Settings > Instrument > Date and time and
confirm.
2. Select the line for editing the date or time and confirm.
3. Select Confirm and confirm with [OK].
10.5 Setting language
1. Select Settings > Instrument > Language and confirm.
2. Select a language from the list and confirm
| en
Instrument settings
is displayed. After
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