Woodward AtlasPC, Руководство по оборудованию

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AtlasPC Digital Control, Vol. I Manual 85586V1
40 Woodward
Analog Inputs
If an analog 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
0–5 V.
•
Verify that there are no or minimal ac components to the analog input signal.
ac components can be caused by improper shielding.
•
Check the wiring. If the inputs are reading 0 or the engineering units that
correspond to 0 mA, look for a loose connection at the terminal blocks and
disconnected or misconnected cables. If the unit is a 4–20 mA input, check
for proper jumper installation on the terminal block.
•
If all of the inputs are reading high, check that the power is not connected
across the input directly.
•
Check the software configuration to ensure that the input is configured
properly.
•
If the input is loop powered, ensure that power is provided externally, the
Atlas control does not provide this power.
After verifying all of the above, the AtlasPC should be returned for service.
Analog Outputs
If an analog output 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.
•
Check the load resistance, ensure that it is less than the specification limit
for the output current.
•
Check to ensure that the load wiring is isolated.
•
Check the wiring, look for a loose connection at the terminal blocks and
disconnected or misconnected cables.
•
Disconnect the field wiring and connect a resistor across the output. If the
output is correct across the resistor, there is a problem with the field wiring.
•
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.