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11.4 Relays
11.4.1 Combinations of latching and
acknowledgment of alarms
The following examples give an overview of relay
acknowledgment combinations.
Latching
(Manual relay reset)
Acknowledge-
Relay reset possible at any time.
able
Non-acknowl-
Relay reset not possible before alarm con-
edgeable
dition cleared.
Latching and non-latching signals are not time-limited.
Latching signals stay active until they are acknowledged.
Non-latching signals stop as soon as the triggering condition
clears.
11.4.2 Configuring relay A1 or A2
This function is used to specify whether the alarm relay is
energized in measuring mode or in the alarm status.
A1/A2 ENERG
The relay contact is energized in measuring
mode and is changed when an alarm is trig-
- ON
gered. In the event of a power failure, an
alarm is triggered (fail-safety).
A1/A2 ENERG
If an alarm is triggered, the relay contact is
energized.
- OFF
1. Select A1 - ENERG - OFF / ON or A2 - ENERG - OFF /
ON.
The display alternates between the current value and
the menu item.
2. Tap [OK].
The value flashes (data entry mode).
3. Modify the value.
● Tap [UP] for energized on alarm (OFF).
● Tap [DOWN] for normally energized (ON).
4. Confirm with [OK].
The value is set and the menu is displayed again.
11.4.3 Configuring the fault relay for the warm-up
time
This function displays the behavior of the fault relay during the
warm-up phase.
The fault relay permanently triggers a con-
FAIL - FREQ -
Stdy
nected alarm indicator (static behavior).
The yellow LED is permanently lit up.
Instructions for use
|
Dräger Polytron 5000 Series
Non-Latching
(Automatic relay
reset after alarm
condition cleared)
1. Select FAIL - FREQ - Stdy / PULS.
2. Tap [OK].
3. Modify the value.
4. Confirm with [OK].
11.5 Configuring alarms
A hysteresis of 5% of the full scale deflection is programmed
into the instruments for the alarms.
status until the gas concentration is outside the defined
interval. This prevents the relay from switching between
energized and de-energized when the gas concentration is
very close to the alarm threshold.
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 can prevent a relay from bouncing when an alarm
threshold is reached.
Setting the alarm threshold
The lowest alarm threshold is a display unit of gas, depending
on the configured sensor type. Select
1. A1 - set or A2 - set.
2. Tap [OK] and set the value for the alarm threshold.
3. Confirm with [OK].
Setting the alarm direction
The fault relay changes status (dynamic
FAIL-FREQ -
PULS
behavior).
Example:
– A signal horn is connected to the nor-
mally open contact of the fault relay.
– The relays are configured as normally
energized.
The signal horn and the yellow LED of
the transmitter are activated for
1 second and deactivated for
9 seconds.
The display alternates between the current value and
the menu item.
The value flashes (data entry mode).
● Tap [UP] for static (Stdy).
● Tap [DOWN] for dynamic (PULS).
The value is set and the menu is displayed again.
Hysteresis is a small interval in which a relay retains its
The display alternates between the current value and
the menu item.
The value flashes (data entry mode).
The value is set and the menu is displayed again.
Rising (ris)
A rising alarm direction means that the gas
concentration must exceed a certain value
for an alarm to be triggered.
Falling (FALL) A falling alarm direction means that the gas
concentration must fall below a certain
value for an alarm to be triggered. Select
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Instrument settings
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