Instrument Settings; Switching The Alarms On Or Off; Configuring Alarms; Testing Alarms/Relays - Dräger Polytron 8900 UGLD Notice D'utilisation

|
en

Instrument settings

c. Remove old sensor.
d. Insert sensor (4) into the opening. The Dräger logo on
the sensor must point to the mark on the sensing head
housing (5).
e. Lock sensor with bayonet ring (3)
f. Tighten set-screw (2).
The display shows: Loading data, please wait
3. When the sensor data are loaded, the display shows: Data
loaded.
4. Select Back to menu and confirm.
 The maintenance signal on the 4-20mA interface
remains pending until the sensor is warmed-up.
5. Perform bump test to check the instrument for proper
operation.
6. Check the installation requirements and instrument for SIL
status.
10 Instrument settings
10.1 Alarms
To avoid false alarms triggered by short ultrasonic peaks,
do not use alarm settings of the instrument without alarm
delay.

10.1.1 Switching the alarms on or off

If the alarm is set to Off, an alarm condition will not be shown
by the LEDs or asserted relays! Using relays the maintenance
signal is transmitted via the 4-20 mA interface and the symbol
is displayed.
1. Select Settings > Instrument > Alarm > Alarm on/off.
2. Select Enable or Disable and confirm.

10.1.2 Configuring alarms

1. Select Settings > Instrument > Alarm > Alarm A1 or
Alarm A2 and confirm.
The current alarm threshold is displayed.
2. Apply settings and confirm the configuration steps
successively with Next.
a. Set value for alarm threshold.
b. Set alarm direction.
Rising The alarm direction is called rising, if the
gas concentration has to exceed a certain
value to activate an alarm.
Falling The alarm direction is called falling, if the
gas concentration has to fall below a certain
value to activate an alarm.
c. Set latching mode.
Latching Once the alarm threshold is reached, the
instrument will trigger the alarm. It will
remain in alarm status even if the gas con-
centration does not meet the alarm condi-
tion any more. To clear a latching alarm it
has to be acknowledged.
18
Non-latching The alarm status clears if the gas concen-
tration does not meet the alarm condition
anymore.
d. Set acknowledgement mode.
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 40 % and hysteresis to 3 %
The alarm stays active until the value falls below 37 %.
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.

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].
Instructions for use
is displayed. After
®
|
Dräger Polytron 8900 UGLD