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PLC problem

  1. Jul 8, 2015 #1
    Hi, everybody today I have got a problem in my Allen Breadly PLC which is after getting emergency HMI shows emergency button pressed and after pull the emergency it can't reset and it was noticed that Plc fault indicator shows blinking. I have checked all corresponding issue & make all things right but the fault indicator still blinking.

    Anybody please help me to rectify this fault.
    Note: The Plc is MicroLogic 1400.

    Your co operation will be highly appreciated.
    Last edited by a moderator: Jul 8, 2015
  2. jcsd
  3. Jul 8, 2015 #2


    User Avatar

    Staff: Mentor

    Can you call MicroLogic technical support?
  4. Jul 8, 2015 #3
    No technical support is not available here.
  5. Jul 8, 2015 #4
    Pure speculation here...

    Does the e-stop circuit kill power to the plc?

    If so, on power up when the e-stop was cleared a fault bit may have been set. Check the s: data table for a set PLC fault bit. If the condition is cleared you may be able to simply set it back to 0. Also if it is an ongoing nuisance problem you could SSV the bit to 0 on first scan or power up. Just make sure it is not a "real" problem with the processor or programming.
  6. Jul 8, 2015 #5


    Staff: Mentor

    As Montoya said, make sure it's not a real problem. The PLC is trying to tell you it's broken. Your ability to diagnose may be too limited in the field.

    Bypassing the warning without fixing the problem may cause more damage.

    Good luck.
  7. Jul 9, 2015 #6
    Thanks to all of you for help,
    but the Plc power is on and the fault indicator floushing, from the Plc manual it's for application fault and it can minimized. So, please help me to minimize this.
    If there are any hardware failure then the fault indicator should solid on.

    Thanks again
    Last edited by a moderator: Jul 9, 2015
  8. Jul 9, 2015 #7
    I understand. PLC power is on and a fault is indicated by a flashing LED on the front of the processor. Everything I said still applies.

    Do you have access to the PLC program and can you view the data tables? RSLogix?

    If you don't you need to get someone with the ability to access the PLC software. The problem may not be solvable from the normal HMI.
  9. Jul 9, 2015 #8


    Staff: Mentor

    In that case, maybe all you need to do is reboot. Disconnect it from all power, wait one minute, then connect again.
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