Woodward AtlasPC, Руководство по оборудованию

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Manual 85586V1 AtlasPC Digital Control, Vol. I
Woodward 39
Troubleshooting Guide
Speed Sensor Inputs
MPUs —If a magnetic pickup input is not functioning properly, verify the following:
•
Check that the cable is shielded and the shield is properly grounded per the
shields and grounding section in Chapter 2.
•
Measure the input voltage on the terminal block. It should be greater than
that shown in Figure 5-3.
•
Verify that the signal waveform is clean and void of double zero crossings.
•
Verify that no ground connection exists and that the resulting 60 Hz signal is
absent.
•
Measure the frequency. Frequency should be in the range of 100 Hz to 25
kHz.
•
Check the wiring. Look for a loose connection at the terminal blocks and
disconnected or misconnected cables.
•
Check the software configuration to ensure that the input is configured
properly.
After verifying all of the above, the AtlasPC should be returned for service.
Proximity Probes —If a proximity probe input is not functioning properly, verify
the following:
•
Check that the cable is shielded and the shield is properly grounded per the
shields and grounding section in Chapter 2.
•
Measure the input voltage on the terminal block. It should be in the range of
16–28 V peak, and the duty cycle should be within the specified range for
the input voltage.
•
Verify that the signal waveform is clean and void of double zero crossings.
•
Verify that no ground connection exists and that the resulting 60 Hz signal is
absent.
•
Measure the frequency. Frequency should be in the range of 0.5 Hz to 3
kHz.
•
Check the wiring. Look for a loose connection at the terminal blocks and
disconnected or misconnected cables. If an open collector probe is used,
check to ensure that the pull-up resistor is installed properly.
•
Check the software configuration to ensure that the input is configured
properly.
•
Verify that the corresponding MPU input is jumpered.
After verifying all of the above, the AtlasPC should be returned for service.