Triac ATC - Drives/Main contactor problem

[sweep]

First off; i'm glad this forum is free
Secondly; this mail is a continuation of my machine problems discussed and pictured on the mail :
viewtopic.php?t=789

So, i've managed to establish that the reason that the toolchanger wasn't working, so far that is, is due to it's supply coming from the Main Contactor located at the side of the Drive boards which wasn't being energised.
When I first got the machine fuse F1 was blown so I have replaced that and also checked all other fuses are ok.
To eliminate a faulty Main Contactor I powered up the machine and then 'made' the contator by pressing (with insulated screw driver) the grey button on the top of it.
When I did this the green LED, just visible in the pic between fuses F1 & F2, briefly lit before both fuses were blown. On the up side power was supplied to the ATC control, main PCB, and spindle DC motor control board. I appreciate at this point I ain't going to get drive to the axis but I pressed the ABS Datum button on the machine front panel. The machine then displayed that it was moving to Z datum, which obviously it wasn't as the drives had fused. I removed my screw driver from the Main Contactor and powered down the machine.
So, looking at the Drive Cards nothing looks too obviously wrong but it took out the fuses so something must be up.

Appreciate any advice ...again!

Thanks ...Richard

[Mr Magoo]

I'd suggets removing the 3 x Digiplan axis drive cards, replacing the fuses then powering up again.

If the fuses stay good then start adding the cards one by one (powering down in between!!!) to see which axis has the fault.
If you find a faulty axis it could be the card that's faulty, or a short on the motor output cables (I've seen a z axis stepper motor cable get trapped inside the column and short out before now).

You can temporarely interchange cards to check if it's a faulty card, but make sure they finally end up back in the right place (becuase the Z axis has a 3 amp card and so a 2 amp card in this slot will give you Z axis stalling problems further down the line)

[sweep]

It lives ...I have movement
The problem with the fuses must have been down to ageing fatigue, if there is such a thing, and the problem with the contactor didn't exist at all. The 'problem' was that I pressed ABS-Datum button before starting the drives; start the drives first and the relay pulls in and then ABS-Datum and we have movement ...well in Z & Y only!
It might sound sad but I hand wound the Z & Y as far away from their datums as possible just to watch them datum again when I next powered up easily pleased.
The X axis still refuses to work so I did a 'T' test and all drives were showing ok so I will strip the motor off tonight and see if we have any supply there.

Also, can anyone advise the correct value of fuse F2, as on page 10 of the maintenance manual, downloaded from this site, it says 3.15A, whilst on page 11 it says 5A?

thanks ...Richard

[Denford Admin]

I'd buy a bag of each - if the 3 amp ones keep blowing, fit the 5 amp

The difference between manuals will probably be down to the fact the the smaller fuses blew more often.
You (hopefully) won't do any damage fitting a 5 amp fuse, but it would be safer to try the 3amp first

[sweep]

That's probably why I blew the 3.15A in the first place! I have some 5A so will try those next.
By the way, my ATC has serial number 001. Do you want to buy it for your museum?
By the looks of all the holes blanked off in the rear electrical enclosures, and the degree of white overspray, it looks like it was probably done as an experimental refit to an existing machine. That would also explain why it came back to Brighouse in 1990 and had a 1990 serial number fitted whilst the main electronics are dated 1988.

...Richard

[Denford Admin]

Do you want to buy it for your museum

No thanks - we've got enough old junk

[sweep]

...can tell you're not from the marketing dept

Your reply should have been:

Denford machine tools will give a lifetime of reliable service, and a machine with such a unique history can only appreciate in value over time. You would be well advised to hold on to this piece of our nations engineering heritage ..blah, blah, blah.

Too right it will appreciate if I could only get the damned thing to work!

...Richard

[Denford Admin]

Don't worry - you'll get there in the end, and you will then have a machine worth its weight in gold

[Mr Magoo]

Take a look at the 2 x 24 pin plugs that connect the umbilical electrics to the machine too. I've known the pins get pushed back into the housing and not make connection.

Hopefully it's just a dodgy connection / broken cable

[sweep]

only wish it was a dicky pin on the plug but I think it is one of the cards!
Swapped over the X and Y cards and that reversed the problem. Checked the surface mounted fuses on the suspect card and they were ok.
Tricked the machine into thinking the faulty axis had datumed and everythin came on line ...even the ATC!

So, does anyone have a spare or redundant PKS-Digiplan SD2/1 card which they could donate, gift, or even at a push, sell me?

Tried the advert from November last year on the classified ads section but all that stuff had gone.

Yours in hope ...Richard

[Denford Admin]

We don't have any here, although there could be some lying around -will have a check.

Otherwise, they do come up on ebay fairly often - do a saved search for "parker digiplan" / "denford" and you will be notified whenever anyone adds relevant stuff to ebay

[sweep]

Would appreciate you having a look just in case.
I have set my ebay searches, one for 'Digiplan' and another for 'Denford' so I will just have to wait and see what appears.

Thanks ...Richard

[sweep]

There is a God!

After scouring my contacts in machine automation (HNC, PAL etc) and pestering people that probably had better things to do, trying to source a new SD2/1 card for the Triac I ended up phoning Parker.
They told me that they did a repair service for the SD2/1 at £96+vat. The bloke then went on to explain that the cards were in fact very simple devices and that normally the only things to fail are one of the two chips and these were readily available off the internet for around £5 each.
Being from Yorkshire I baulked at spending £96+vat but £5 didn't sound that bad. As the main chip was plugged into the board I decided to swap it over with the chip on the good board to confirm that it was faulty.
I then refitted the boards and powered up the machine only to find I had movement on ALL axis
The problem must have been a 'dry' or corroded connection on one of the chips pins and swapping them over must have solved it.

Now watch out for my posts asking how to program the machine.

Richard

[bradders]

God must have thought it was easier to perform a miracle on an electronic device than trying to perform an unachievable miracle of getting us Yorkshire folk to part with some brass!!!!!!!!!!!!!!