584,812 active members*
5,484 visitors online*
Register for free
Login
Results 1 to 5 of 5
  1. #1
    Join Date
    Jun 2015
    Posts
    13

    FANUC 0MF VRDY OFF ALARM 401

    Hi
    I need emergency help to solve a fault in FANUC 0MF
    The problem: ALARM 401 + VRDY OFF (no more alarms)
    1. INTERFACE CABLE JX1B-JX1A = OK
    2. TERMINATING DUMMY CONNECTOR = OK
    3. X021.4=1 G121.4 G230.1 *ESP *ESPA SIGNALS OK
    4. EM. STOP SIGNAL IN THE PSM CONNECTOR CX4=OK
    5. THE EM STOP SIGNAL LINE (PIN 3 OF CONNECTOR CX2A CX2B BETWEEN THE PSM SVM AND SPM OK (24V)
    6. I CHECK MCON SIGNALS TO ALL AXES :THE LEVEL SIGNALS GO FROM HIGH TO LOW FOR 2 SEC AND GO BACK TO HIGH
    7. I CHECK THE MCCOFF PIN 7 IN OUT OF SVM ITS GO TO LOW ALSO FOR 2 SEC
    8. I CHECK THE MCCOFF PIN 7 IN THE INPUT OF PSM THIS SIGNAL GO TO LOW LEVEL
    9. THE READ RELAY CONTACT ( IN PSM CONNECTOR CX3) Completely NOT WORK (Not work even for a second)
    (And therefore main contactor not working )
    (PSM replaced
    Axes card replaced)
    Please what should I check to solve the problem ?
    Thanks
    David Relevi [email protected]
    PSM:A06B -6077-H111A
    SPM:A06B-6078-H211 #500
    Y Z AMP: A06B-6079-H206A
    X AMP :A06B -6079-H103A

    VERTICAL MACHINING CENTER
    MODEL: MCV-610CR
    SERIAL NO:LISIE0127
    MFG DATE :JUL. 1995
    CNC UNIT
    MODEL :FANUC-0MF
    MFG NO:T95420136

  2. #2
    Join Date
    Apr 2015
    Posts
    10

    Re: FANUC 0MF VRDY OFF ALARM 401

    Hi have you checked the overloads for the drives in the back cabinet and also all fuses , obvious i know but sometimes missed and make sure they are reset, i have had this alarm before , check your parameters ( hope you have listing), they have a habit of dissapearing sometimes on the fanuc T systems..

  3. #3
    Join Date
    Jun 2015
    Posts
    13
    Quote Originally Posted by desmond4518 View Post
    Hi have you checked the overloads for the drives in the back cabinet and also all fuses , obvious i know but sometimes missed and make sure they are reset, i have had this alarm before , check your parameters ( hope you have listing), they have a habit of dissapearing sometimes on the fanuc T systems..
    thank you
    do you know parameter no to check for this alarm ?

  4. #4
    Join Date
    Apr 2015
    Posts
    10

    Re: FANUC 0MF VRDY OFF ALARM 401

    Quote Originally Posted by RASH1 View Post
    thank you
    do you know parameter no to check for this alarm ?
    The machine will be disabled if any parameter has been corrupted, the 401 alarm is not specific to a fault it is telling you that conditions to start up are not being met.
    if there has been a collision or machine has stood for a while , with power off try to manually rotate the lead screws a little .
    also check that all 3 phases are being fed to machine. from source and then from feed inside machine. check over/travel switches and make sure emergency stop button is ok.
    for the parameters you need to scroll through them and check the bit number sequence is correct to the factory settings.

    eg paremeter
    1 00001011
    2 11000010
    3 00000011
    there is a parameter disable switch on the memory board in the cabinet that needs to be flicked up if change of data input is needed.

  5. #5
    Join Date
    Jun 2015
    Posts
    13

    Re: FANUC 0MF VRDY OFF ALARM 401

    thank you

    I test :the control sends a signal ENABLE *MCON to servo also *mccoff is ok (PSM JX1B PIN 7)go to 0volt !
    This means that the machine ladder right?and the parameters ok ?
    The problem must be in only in the servo ?
    It cant be limit switch or sensor like air, oil and……..others sensors ?

Similar Threads

  1. Replies: 29
    Last Post: 07-12-2023, 01:43 PM
  2. VRDY OFF Alarm
    By NID in forum Fanuc
    Replies: 12
    Last Post: 04-02-2014, 07:49 PM
  3. Replies: 0
    Last Post: 01-28-2013, 12:55 AM
  4. Alarm 403: VRdy off , Fanuc OM
    By ThomasS in forum Fanuc
    Replies: 8
    Last Post: 07-27-2012, 01:39 PM
  5. 401 alarm (VRDY OFF)
    By sting007 in forum Fanuc
    Replies: 4
    Last Post: 03-20-2007, 02:47 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •