Checking The Alignment Of The Gas Warning System; Calibrating The 4 To 20 Ma Interface - Dräger Pulsar 7000 Serie Instrucciones De Uso

en Maintenance
6.3.2

Checking the alignment of the gas warning system

If no DIGITAL LINK connection is installed, alignment mode needs to be switched on separately at the transmitter and
switched off again before zero calibration is performed.
1. Check that the gas warning system is correctly aligned.
a. Connect the Pulsar Interface Adapter to the receiver communication port and switch on the communication mode.
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b. Connect the HART
c. Establish communication on the HART
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d. On the HART handheld terminal, select 5 / Maintenance in the main menu.
e. In the 5 / Maintenance menu, select 1 Start alignment.
Active must be displayed next to 3 Alignment Mode.
The maintenance signal is output on the 4 to 20 mA interface.
The green LEDs blink on the transmitter and receiver.
f. In the 5 / Maintenance menu, select 4 Graphical alignment.
Select 1 Alignment graph.
g. Ensure that the measuring points of the transmitter and receiver on the HART
divisions from 0.
2. If the measuring points are not within the desired range, align the gas warning system (see Chapter 4.2.6 on Page 52,
step 6.).
3. Perform a zero calibration (see Chapter 4.2.5 on Page 51, step 8.).
6.3.3

Calibrating the 4 to 20 mA interface

NOTICE
For the duration of the maintenance work, deactivate the alarm function in the control unit if necessary. During the maintenance
work, the gas warning system issues current values of 4 mA to 20 mA.
Dräger recommends a zero calibration before the 4 to 20 mA interface is calibrated. On the HART
measured gas value and the output current are displayed under 2 / Measurement values. If the digital display of the
measured gas value is 0.0 LELm and the 4 to 20 mA signal in the control unit deviates from 4.00 mA, Dräger recommends
calibrating the 4 to 20 mA interface.
The current ranges in which the 4 to 20 mA interface can be calibrated are significantly smaller than ±0.5 mA around
4.00 mA or 20.00 mA. A permanent current signal that is too low or too high can indicate a small gas concentration or that
the zero-point is no longer correct.
A suitable ammeter must be used for calibration. This must be integrated as closely as possible to the control unit so that
the current of the 4 to 20 mA interface can be measured with sufficient accuracy.
1. Connect the Pulsar Interface Adapter to the communication port and switch on the communication mode.
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2. Connect the HART handheld terminal to the Pulsar Interface Adapter.
3. Establish communication on the HART
4. In the 6 / Analog config menu, select 8 4-20 mA calibration.
The LEDs on the receiver indicate the "Calibration of the 4 - 20 mA interface" state.
5. Follow the instructions on the HART
Enter the value from the ammeter for "4.00 mA output".
Enter the value from the ammeter for "20.00 mA output".
6. Repeat step 5 as necessary.
7. Exit the 8 4-20 mA calibration function
The gas warning system changes to measuring mode.
The LEDs indicate "Measuring mode".
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8. Exit the HART application.
1) The gas warning system exits the 4-20 mA calibration mode automatically after 1 hour and returns to measuring mode.
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handheld terminal to the Pulsar Interface Adapter.
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handheld terminal via the Device Description.
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handheld terminal via the Device Description.
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handheld terminal:
1)
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handheld terminal are less than 30 scale
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handheld terminal, the