Troubleshooting

The method of communication used is an RS-485 daisy chain. This, in effect, puts all machines in parallel making troubleshooting somewhat difficult.

The three most common symptoms are as follows:

1. One machine does not communicate.
2. All the machines on one line do not communicate.
3. All the machines on all lines do not communicate.

Troubleshooting procedures:

1. One machine does not communicate:
   1. Exchange the IA with an IA from a machine that is communicating making sure to set the correct machine numbers. If the problem moves to the other machine, the IA is defective and should be shipped to Murata of America, Inc. for repair service. If the problem remains with the original machine number - go to step 2.
   2. If the IA in question is an IA/2 or an IA/3 - correct the communication line wiring defect.
      If the IA in question is an IA/1, inspect the wiring connections inside the interface converter. If the wiring is good, exchange the interface converter with one from another (working) machine. If the problem moves with the interface converter, contact Black Box for repair or replacement. If the problem remains with the machine, correct the communication line wiring defect.
2. All the machines on one line do not communicate:
   1. Separate the communication line into two parts making the separation in the middle of the line. Wait 30 minutes (this time may be longer or shorter depending upon the scan time of your system). If the machines in the first half of the line begin to communicate, the problem is in the second half of the line. Use this procedure (dividing the line in half) in the second half of the line to run the problem down to the perpetrating machine. If the machines in the first half of the line do not begin to communicate, apply the separation method (described previously in this step) to the beginning of the line. After locating the problem device, go to step 2. If the IA's in question are IA/1's, this troubleshooting method will be applied with respect to the interface converters. If the problem is caused by an interface converter, contact Black Box for repair or replacement.
   2. Ship the defective IA to Murata of America, Inc. for repair service.
3. All the machines on all lines do not communicate:
   1. Restart the computer.
   2. Restart the polling module (this should start automatically after the computer restarts).
   3. If the problem remains after steps one and two, you may have a problem with the computer. Contact your data processing department or local computer store to have diagnostics run on the computer. If you still cannot resolve the problem, contact the vendor from whom you purchased the MJS32 software for assistance.

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