Dräger Polytron 8000 Serie Instrucciones De Uso página 31

b. Set the alarm direction.
The alarm direction is called rising if the gas
Rising
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 the latch mode.
Latching Once the alarm threshold is reached, the
instrument will trigger the alarm. It will
remain in the alarm state even if the gas
concentration no longer meets the alarm
condition. To clear a latching alarm, it must
be acknowledged.
Non-latching The alarm state clears if the gas concentra-
tion no longer meets the alarm condition.
d. Set the acknowledgement mode.
Acknowledge- The alarm relay and the alarm LED can be
able reset before the alarm condition clears.
Non-acknowl- The alarm relay and the alarm LED cannot
be reset until the alarm condition clears.
edgeable
The alarm state can be acknowledged
Pre-Acknowl-
edgeable before the alarm condition clears. The
alarm relay and the alarm LED stay active
until the alarm condition clears, however.
e. Set the hysteresis value.
The hysteresis function defines a range in which a
triggered relay will remain in its state until the gas
concentration is outside the defined range again.
Example: The alarm threshold is set to 40 ppm and
hysteresis to 3 ppm. The alarm remains active until the
value falls below 37 ppm. This prevents relays from
closing and opening in rapid succession at an alarm
threshold ("chattering").
If the direction of an alarm is changed (from falling
to rising or vice versa), the hysteresis value must be
checked and corrected if necessary.
 A confirmation screen shows all settings.
f. Select Confirm and confirm with OK.
✓ The new settings are saved.
11.9.3 Testing alarms/relays
These functions change the statuses of a relay and an LED
for test purposes (e.g., to check the function of alarm devices
connected to the relay). The
exiting this function, the statuses of the relay and the LED will
automatically return to their previous statuses.
Instructions for use |
Dräger Polytron
symbol is displayed. After
®
8000 Series
1. Select and confirm the desired alarm condition via
Settings > Instrument > Alarm.
Set Alarm A1 Simulates a pre-alarm
Set alarm A2 Simulates a main alarm
Set fault Simulates a fault signal
2. Select and confirm Enable.
 The fault relay is de-energized and the 4 to 20 mA
interface is set to fault current. The yellow LED is lit,
the symbol for maintenance is shown.
When the menu is exited, the simulation is ended.
11.10 Data logger settings
11.10.1 Displaying graph
The last 15 minutes as a time/concentration graph can be
viewed.
1. Select Information > Data logger > Graph
11.10.2 Switching data logger on or off
1. Select Settings > Data logger > Datalogr. on/off and
confirm.
2. Select Enable or Disable and confirm.
11.10.3 Setting the sampling time
This function defines how often a value is stored.
1. Select Settings > Data logger > Datalogr. on/off >
Sample time and confirm.
2. Select the sample time and confirm.
11.10.4 Setting peak/average
This function determines which value is stored.
1. Select Settings > Data logger > Data logger >
Peak/Average and confirm.
2. Select Peak or Average and confirm.
Peak
Average
Instrument settings |
The maximum value (if moni-
toring falling concentrations,
the minimum value) of the
measured concentrations
within the selected sampling
time is stored.
The average value of all the
measured concentrations
within the selected sampling
time is stored
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