[stevieboy]

BMC 20 Ultimax 3.

Over the past year or two I've been getting several different errors with this machine that stop it running. These have been:

Magazine reference limit switch not seen.
ATC. Error. magazine is not in position.
Encoder fault on axis S.
Servo drive fault on axis S.
Servo drive fault on axis Y.

It throws up a different one of these most times but will run fine for a period of time in between. The ATC errors can be sorted by rotating the carousel in diagnostics. The servo drive and encoder errors need a reboot to clear but it's fine afterwards. However the latest one, Servo drive fault on axis Y seems to be there for good this time.

This is what I can't understand. The machine will switch on and calibrate no problem. I can also do a warm up and feed/rapid the table around ok. If I go to start the spindle at anything above 2000 RPM though it trips out and throws up the error Servo drive fault on axis Y. There can't be anything wrong with axis Y as it moves about perfectly ok.

If I go to run a program it will select the tool and rapid to the start position. Then it starts the spindle and straight away trips out as the revs build up. I can set the manual spindle speed to 2500 RPM, turn the override right down and then start the spindle in manual but as I slowly turn up the override it gets almost to 3000 RPM and then trips out with the warning Servo drive fault on axis Y.

I'm going to ring the service department on Monday morning but has anyone on here any ideas what it could be.

[bloke]

Check the spindle drive for an error code after it has faulted.
Post it bere and I may be able to help.

[stevieboy]

Hi Bloke,

There's no error code on the spindle drive however there is an alarm number 3 on one of the axis drives. This is on the left of the cabinet under the power supply. I presume this is the Y axis drive. I spoke to Roy in service this afternoon and he was thinking high speed contactor but wanted some photos of inside the cabinet to see if it had one or not.

Doesn't it allways stop in the middle of a big job that needs to be finished.

Any ideas?

[stevieboy]

Update.

I spoke to Roy after he looked at all the photos I sent him and said there doesn't appear to be a high speed contactor but to check all the voltages to the spindle drive. I get a good 200 volts to the PKZM 1-10 contactor and the same out. I also get a good 200 volts going into the spindle drive accross all 3 phases (R,S,T,). With the spindle running at 500 RPM it was showing 890 volts accross U,V,W.

I can get the spindle to run right up to max rpm of 6000 by setting the manual spindle speed at 2500 and starting it in manual with the override turned right down then slowly turn it up. I'll leave it running for a couple of minutes and then repeat but with a higher setting typed in untill eventually it's set at 5500, starting ok with the dial turned down and then slowly turn it up to max. It will run like that ok, I can even turn the dial up and down as quick as I like and the revs go up and down with it.

If I set the manual speed to 3000 and start it with the override in the middle it will start off but then trips out as the revs build up. The thing that's baffling is why does it report an error on the Y axis.

I can right a quick program with drilling ops all over the bed and a low spindle speed of 1000 RPM and it will go through the program fine, rapid traversing from one location to the next.

I forgot to mention there was a power cut on saturday, luckily it happened as I was changing the material but it was only out for about 5 seconds and came back on before I managed to get round the back of the machine to turn the main switch off.

Any ideas?

[bloke]

There should be a contactor in a box (about 8" square box) that isolates the machine when the back doors are opened. This may need to be taken out of the circuit and have the the contactor removed. They were known to cause all sorts of problems. If you take the thick cable from the bottom of phase one and connect it to the top cable in phase one using the contactor terminal to join them, it will stop the connection jumping out if the contacts are bad. Repeat for the other two phases.

[stevieboy]

Ok I tried that and it made no difference Bloke.

I managed to run a couple of programs last night by setting all the tool speeds to 2500 in the program and then have the override turned right down when it selects a tool. Then press motion hold, turn the speed right up and release hold. I slowed the feed down as well accordingly. It got progressively worse tripping out at a lower and lower speed until in the end I gave up.

This afternoon I switched it on and went to do a calibrate and it tripped as soon as the table moved. Now if I switch it on and go Manual, Power, start it cuts out straight away, within a second of the servos being powered up. The same error appears on the screen, "Servo drive fault on axis Y", and an alarm number 3 on the drive. Is it possible the spindle powering up is causing a slight current drop and if the axis drive was on it's way out this was causing it to trip out and report a fault?

[stevieboy]

Ok, now I know exactly where the problem is. I swapped the X and Y servo drives around in the cabinet and it does exactly the same thing but this time faults out in the X axis with the same alarm number 3. So it was the Y axis servo drive going bad and I guess a slight current drop of the spindle starting up was just making it faint. I suppose I just needed it to fall over completely before I could find the fault. It must of had a spike of some kind when the power went out.

So can these be repaired or will it have to be replaced. The number on the side is CACR-SR-10BB1BF. Also, once I've got one sorted will it need to be adjusted when fitted to the machine?

What do you think Bloke?

[bloke]

They can be replaced by Yaskawa but the cost is very high. Your fault indicates a fault in the regen circuit of the drive. It may just need a new regen resistor fitting (the odd looking white block under the main board) or it may need a new control card.
If it is swapped, it'll need the signal voltage setting up and the zero offset adjusting.

[stevieboy]

Cheers Bloke,

Got one of the hurco guys coming out to it on Tuesday next week to fit a second hand drive and set it up. I couldn't afford a new one from Yaskawa at £1200 plus £500 for installing, plus VAT although it would have been nice to have a new one.

Thanks for all your help.

[hurco_man]

Maybe i am too late, but question. When you swap X and Y servo drives did you swap and power cables to it or just data cabels? If you left power source same, doesnt have to be servo drive.

[CORN11]

Hello Mr BLOKE

I have a project at home regarding servo motor, already buy a Panasonic servo driver MADDT1207. But my problem is My PANASONIC SERVO DRIVER always giving ERR 60 when i connect the power supply. Any component spoil in my servo driver or got any method to clear the ERROR 60.