Interface Settings; Full Scale Deflection; Setting Maintenance Signal; Testing The Analog Interface - Dräger Polytron 5000 Série Mode D'emploi

en

Interface settings

2. Tap [OK]
 The value flashes (data entry mode)
3. Set the wire configuration.
● Select [UP] for 2-wire configuration (2-on)
● Select [DOWN] for 3-wire configuration (3-on)
4. Confirm with [OK] and exit the menu.
5. Cycle power to the instrument and ensure the setting of
this function matches the wiring for power and signal.
13 Interface settings
13.1 4-20mA interface
The current output of the instrument during normal operation
is between 4 and 20 mA and is proportional to the detected
gas concentration.
®
Polytron 5xx0 uses different current values to indicate
various modes of operation. The factory default settings are
user adjustable for application specific requirements. This
follows the NAMUR recommendation NE43.

13.1.1 Full scale deflection

®
Polytron 5100 EC and Polytron
Some sensors offer an adjustable full scale deflection to limit
the measuring range for the 4-20 mA interface.
The full scale deflection (FSD) sets an endpoint within the
measuring range of the sensor. If the gas concentration
reaches this endpoint, the 4-20mA interface transmits 20mA.
Example: Required range 0 to 500 ppm CO (e.g. part number
6809605 default 300 ppm, range min/max = 50/1000
ppm).Select full scale deflection as 500 ppm. The analog
output will be linear between 4 mA = 0 ppm and 20 mA = 500
ppm.

13.1.2 Setting maintenance signal

Configuring the maintenance signal.
The maintenance signal is transmitted on the analog output
anytime the menu is accessed.
Steady (Stdy) a steady 3.4 mA output signal
Dynamic (3-5) an oscillating 3 to 5 mA signal with a fre-
quency of 1 Hz
1. Select CAL - set
 The display toggles between the current value and the
menu item.
2. Tap [OK]
 The value flashes (data entry mode).
3. Set acknowledgment mode.
● Select [UP] for dynamic (3-5)
● Select [DOWN] for steady (Stdy)
4. Confirm with [OK].
The value is set and the instrument returns to the menu.
®
57x0 IR only
13.1.3 4-20 mA offset
Configuring the 4-20mA offset is a 2-step process. First the
offset for the 4mA output (Adj - 4 ) is set, then the 20mA (Adj
- 20) output is set.
4mA output This function adds an offset to the analog
(Adj - 4 ) output at 4 mA.
The limits can be set between 3.8 mA and
4.2 mA.
20mA output This function adds an offset to the 20 mA
(Adj - 20) analog output.
The limits can be set between 19.5 mA and
20.5 mA.
1. Match the current output with the reading at the control
unit.
To adjust the current output at the transmitter:
2. Select Adj - 4
3. Tap [OK]
 The value flashes (data entry mode).
4. Change the value using [UP] and [DOWN].
5. Confirm with [OK].
 Adj - 20 is displayed.
6. Tap [OK]
 The value flashes (data entry mode).
7. Change the value using [UP] and [DOWN].
8. Confirm with [OK].
The value is set and the instrument returns to the menu.
Polytron 57x0 (IR)-specific
The transmitter displays 4 - Adj - OK or 4 - Adj - FAIL after
changing the value for Adj - 4 and confirming with [OK]. The
same goes for the 20mA output.
If 4 - Adj - FAIL is displayed, the PIR 7x00 sensor could not
trim its output to match the entered value.
Retry to trim the offset.

13.1.4 Testing the analog interface

These functions change the current of the analog interface for
test purposes (e.g. to check the programming of the control
unit). It might be necessary to inhibit the alarms at the control
unit to avoid false alarms.
1. Select 4-20 - test
2. Tap [OK]
 The value flashes (data entry mode).
3. Change the value using [UP] and [DOWN]
 The current output is adjusted accordingly.
4. To end the test, tap [OK].
The currents automatically return to the maintenance
signal and the instrument returns to the menu
®
Dräger Polytron 5000 Series