Parker OEM750, User Manual

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OEM750 •
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Troubleshooting
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6. Use the ohmmeter to check the resistance between Phase B and Earth (the motor
case shaft). It should be infinite.
7. Turn the shaft manually. There should not be any torque.
If the motor responds as described to each of these steps, it is
functioning properly. The source of the problem is probably
within the drive.
RS-232C Problems
Use the following procedure to troubleshoot communication
problems that you may have with the OEM750X.
1. Be sure the host computer’s transmit (Tx) wire is wired to the peripheral’s receive
(Rx) connection, and the host computer’s receive (Rx) wire is wired to the
peripheral’s transmit (Tx) connection. Switch the receive and transmit wires on
either the host or peripheral if the problem persists.
CAUTION
OEM750X Rx, Tx, and GND pins are not 2, 3, and 7 like most devices.
2. Confirm that the host and peripheral are configured for the same baud rate, 8 data
bits, 1 stop bit, and no parity.
3. Use DC common or signal ground (pin 7) as a reference, not earth ground.
4. Cable lengths should not exceed 50 feet (15 m) unless you are using some form of
line driver, optical coupler, or shield. As with any control signal, be sure to shield
the cable-to-earth ground at one end only.
5. To test the terminal or terminal emulation software and the RS-232C cable for
proper three-wire communication, unhook the OEM750X and enter a character.
You should not receive an echoed character. If you do, you are in half duplex
mode. Connect the host’s transmit and receive lines together and send another
character. You should receive the echoed character. If not, consult the manufac-
turer of the host’s serial interface for proper pin outs.
Software Debugging Tools
The OEM750/OEM750X has several tools that you can use to
debug a problem in the system. The software tools are listed
below:
RA Limit Switch Status Report
R Report Status
IS Input Status Report
BS Buffer Status Report
B Buffer Status Report