IRB4400 M98A S4 boot error

    Hi All


    Newbie to Robots here I have an irb4400 m98a with S4 controller. Acquired it a few months ago and at first it would boot ok but had several intermittent errors. Few days ago I powered it up however it will not boot anymore and displays startup error as per picture


    I do not have any discs or backups with the robot nor have I ever successfully got it to motors on stage


    Any help appreciated

    I have checked all cables and connections a few times, I have also replace the backup battery’s in the controller 1 at a time so system always had backup power.


    The battery pack on the resolver board is only showing 1 volt so I will replace it ASAP any other ideas?

    It's a shame you didn't get a backup while it would still power up. The backinfo file would have said which version of software it had. If for some reason you have to load software, you must NOT install RW3.1 if it had RW3.2 installed.

    Was the controller on when you replaced the batteries? Should always change them with the power on.

    The power supplies are susceptible to going bad with time. Seen noisy power supplies also cause this. The AC component on the DC voltages should be <50mV on a digital meter.

    It was not on when battery was changed however only one battery I dead so I changed the dead one first followed by the second battery so the power was never fully interrupted.


    I has booted successfully since the battery change


    I did managed to get it to boot yesterday I have attached a photo of the Teach pendant errors


    I had a feeling it could be a bad power supply as when running the fan RPM seems to fluxuate constantly which doesn’t sound right would this be inline with power supply issues ?


    Can you give me the steps to backup if I do get it to boot ok. FYI it has a USB port inplace of the FDD drive

    Can't remember that there are two redundant batteries. One is for the serial measurement board (in the robot socket) , one is for the cpu memory (consists of two serial connected batteries, in the cabinet).

    So You have good chance that you killed the system software.

    It has booted successfully since I did the battery change, that particular boot show a resolver error so I checked cables on robot and I did a reboot and it cleared the resolver error, I have never been able to get a green EN light or Motors on.

    Glad it was able to boot. You should do a backup ASAP!!


    Regarding the 2 controller batteries - it's unusual to have one good and one bad. Glad you were able to change them correctly although I always measure the new batteries first and then change them with the power on to ensure no issues.


    The power supply fan variation may indicate a power supply issue or it could just be going bad. Checking the DC outputs levels and the AC component of each one is needed to verify its operation.


    Regarding 'Error 38001' - did you check the SMB battery pack in the base of the robot? This is also done with the power on. If it is a 6-cell NiCad pack, the controller should be on for 24 hrs to ensure it is fully charged. If it is a 3-cell Lithium pack, it should be replaced be a 6-cell NiCad pack per ABB.


    Regarding the 'EN' (Enable) LED - check the error log for another system error. You can save the log file and post it if you're unsure about the errors.

    Thanks the SMB Pack is a 7.2v 6 cell pack although I didn’t check the chemistry but I would assume nicad going by what you say.


    I will do some more investigating today re error logs

    Update: the SMB battery pack is good but still showing error 38001


    I noted a faint hi pictched constant beep type tone coming from the SMB is this normal ?

    The 38001 error solution ABB suggests is that the battery pack may be the issue, but it could be the Serial Measurement Unit itself. I don't remember high pitch sounds from a good one, but the upper range of my hearing has diminished over the years.

    I've also had issues with intermittent battery connections dropping the rev counter.

    Interesting you comment regarding the rev counter as that was a consistent error when I first got the robot. With the controller powered on (1 hour) I removed the SMB Battrey pack and it was reading 8.3v waiting 5 minutes and 8.1v so I reconnected. I guess I could load test the pack.


    Also with reference to the main power supply transformer at the base of the control box. I couldnt find the specs in the manual but the on/off switches for each circuit are labeled something like 200v, 240v, 400v, 440v if I test each terminal I’m only getting 100v 120v 300v 330v respectively. Dose anybody him the specs and or correct procedure to test the main PSU ?

    The NiCad battery pack is rated at 7.2V (6 x 1.2V) but typically reads closer to 8V when fully charged. It loses the overcharge voltage at a faster rate but should flatten out around 7.4 to 7.7V.


    I measure the power supply voltages at the connectors on the front. For the M98A circuit diagrams, see page 365 of this manual > M98A IRB2400 Product Manual

    Thanks SK. I’m certain the T1 voltages are well Down compared to spec in the manual which I’m assuming indicates the Transformer requires replacing ? Or to be rebuilt ?


    Does anyone have any experience running robots on Aftermarket controllers? Most of my experience is from CNC some of which is using Linux Cnc Software which when paired with Mesa hardware can control 6 axis robots via CAD/CAM

    How low are the voltages? ABB specs for incoming voltage are -15% to +10%. The ideal voltage to the power supply is 55VAC 3-ph and 262VAC 3-ph going to contactor K1.


    The transformer is tapped for different incoming voltages, make sure the incoming voltage and the transformer jumpers match. If you're not sure, post the transformer part # and what the incoming voltage is. Page 363 (diagram sheet 12) in the previously mentioned manual gives the transformer jumpers needed.


    To get an answer in general regarding aftermarket controllers, I would start a new post in the General Discussion of Industrial Robots Only. If it's specific to only ABB, then start a new one here in the ABB forum.

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