Cyclone TU150-P - 401 VRDY OFF alarm

[ti nut]

Hi all,

We have a ‘96 Cyclone TU150-P with Fanuc 0T-C which has had a few problems recently. We’ve been racking out heads (with very limited knowledge!) on how to fix the machine so any help would be really appreciated!

The machine throws a 401 VRDY OFF alarm on start up. On hitting Reset, the alarm disappears -> after a couple of seconds the magnetic connector (MCC) pulls in (and stays in) -> there’s a click from one of the Fanuc servo amplifier units (after a couple of seconds), which throws the MCC up again -> setting off the 401 alarm.

The post on the VRDY alarm was helpful: viewtopic.php?f=4&t=3413

The issue was temporarily resolved (for a whole 5 minutes!) by disconnecting and reconnecting a bunch of cables, including the ones running from the servo amplifier to the motherboard. It is not clear whether the issue lies with the Honda cables or the connection of the board to the motherboard or another cable?

Not sure if pulling the boards from the motherboard is advisable (risk of losing memory)?
The Honda connectors seem really fiddly to have to solder so any tips on what might be wrong with connections, or advice on how problematic it might be to remove the boards from the motherboard, would be super helpful!

Some pics attached (new to this so took a while just to figure out the basics – hope this can help other newbies).

Many thanks in advance!

[Martin]

Can you post a picture of the relays?

[ti nut]

Hi Martin,

Thank you for your reply and sorry about the super long delay in getting back.

Attached is a photo (of what I think are) the relays.. Let me know if these are OK, can post more photos if not.

A post from 2010 (viewtopic.php?f=33&t=2514) seems to suggest the 401 alarm might be due to a fault with the drive or a loose wire tripping the drive.

We don't have electrical drawings for Fanuc 0T-C so are working blind when it comes to checking connections.
We've looked for drawings online but haven't managed to find any (somehow found 21i, 0T-A and 0T-B drawings from various periods - just not the ones we need!).

Did find various manuals for the 0T-C on https://cncmanual.com/fanuc/fanuc-0-tc/ May be obvious but again, hope it can be of use to fellow newbies.

Any help/pointers would be really appreciated!