Earthshaker transformer

[robm]

As mentioned in another thread, i just picked this earthshaker up.  The bloke was playing it and it let a puff of smoke out and stopped.  The pics are of the power supply board that obviously has had some trouble.  When we turned the machine on (with the power supply board disconnected) it tripped the safety switch in the house.

When i got it home, disconnected everything after the transformer and turned the machine on, there was quiet sizzling noise (1 second) and a small bit of smoke coming from the transformer as well as a burning smell.  This time it did not trip the safety switch in my shed.

I'm assuming the transformer is stuffed.  The part number is 5610-12136-00.  The question is, do i run and get (dunno from where) a new transformer or get it rebuilt or something else???

Also is it a reasonable assumption that the transformer is the problem? - i looked in the box where the lead comes in and everything looks very clean and no sign of any shorts or something sinister.

[MartyJ]

Can you post a pic of the transformer?

I know sometimes the transformers have to be jumpered to suit local voltage.  From the Williams stickers inside the cab - was it an export?

Either way, smoke and hissing from it is not good...but easy to replace.  Check with MarkC - he may even have a spare floating around.

[ajlaird]

OK, it was working - do we know how long it had been working before it died? Weeks, days, hours?

I assume that is a voltage regulator that has been cooked there? I wouldn't be too hasty in connecting up a replacement PSU or transformer until the reason the problem occurred in the first place is addressed. You might just end up cooking the replacement as well. A good look through the schematics would be in order to find out what lives at the other end of that particular supply rail - for example, I wouldn't be surprised if the shaker motor has some sort of problem - but it could be anything really. Check that the fuses are correct, too - if they aren't this might give you some clues.

I guess a faulty transformer could cause the problem on the power supply board, but I am suspicious that the problem lies on the other side of the PSU? That is, whatever caused the voltage regulator to cook may have caused damage to the transformer at the same time.

Someone with more experience will be able to give you more insight.

[robm]

Thanks for the replys - will go out and check fuse ratings now

The machine i understand was working fine for a number of weeks for the previous owner.

The machine looks to be an aussie delivered one as the sticker says 220V.

Below is a pic of the transformer...

[robm]

Just checked the F2 and F3 fuses on the power supply board which according to the manual should be 1/8 A  250V - the ones in there have 10A stamped on the end and no marking if they are 12 or 240V - unsure if this will make any difference?

[ajlaird]

Just checked the F2 and F3 fuses on the power supply board which according to the manual should be 1/8 A  250V - the ones in there have 10A stamped on the end and no marking if they are 12 or 240V - unsure if this will make any difference?

Sounds like a major problem to me - if they are meant to be 1/8A and they are 10A then the problem was allowed to cook the board rather than blow the fuse. I forget whether you can substitute 12V with a higher rating for 240V with a lower rating, but even if this was the case 10A is still way too high.

I would still be trying to determine if there is a problem along the line.

[robm]

Will continue checking down the line - i guess the thing is the transformer made some smoke and burnt a bit when we had nothing connected - just power into the transformer.  But as suggested the problem may have occurred further along the line - half stuffed the transformer and now it is continuing to 'cook' even with nothing connected?

[ajlaird]

Will continue checking down the line - i guess the thing is the transformer made some smoke and burnt a bit when we had nothing connected - just power into the transformer.  But as suggested the problem may have occurred further along the line - half stuffed the transformer and now it is continuing to 'cook' even with nothing connected?

That's exactly what I would be wary of.

I have done a bit more reading on fuses and I am still not certain exactly of what the voltage ratings mean, but a 10A fuse in place of 1/8A is a disaster waiting to happen whether it was rated 12V or 240V. Hence the burnt board.

I will try to look at the schematics if they are online so I can better understand what might have happened.

[robm]

Have checked all the fuses and there are some that are amiss.  There are quite a few that are not marked 250v so i assume these are 12v as most of them are much higher amperage than specified.

On the power supply board
F1 is 10A 12v  should be            3/8 A 250v
F2 and F3 are 10a 12v should be 1/8 250v

On Aux Power driver board

F4 is 5A 250 should be 2 1/2A 250
F5 is 15A 12v should be 2a 250
F6 is 30A 12v should be 2a 250
F7 is 15a 12v should be 4a 250

On Interconnect board

F2 is 5A 12v should be 5a 250

Then there is another fuse that is the "+18vdc Lamp Ckt/ Lwr Rt Backbox Fuse Holder" which should be 8A 32V - it is an 8A but 250v and is a strange ceramic looking centre bit (instead of glass) and when tested on the multimeter - there is no continuity but a resistance of around 320 k ohm. (see pic)

So i don't know if this is a potential culprit, but i will certainly grab the correct other fuses for future testing.

[MartyJ]

Rob,

The first thing I always do with any new machine is (a) remove all fuses and check with DMM and ensure it is correct type before it goes back in.  Next is to visually inspect everywhere - ie behind displays, under playfield, on top of bumper coils etc... for any loose screws which may have come loose and shorted out G.I strings or your switch matrix.

Given that you've disconnected the 'out' / playfield side of transformer and it smoked and popped, me I would get this checked first.  I've never seen a transformer with that much corrosion on it.  ??  Is there any marks on the bottom of the cabinet - ie if someone has spilt something on it perhaps?

Once you know the transformers AOK, then as Ajlaird rightly suggested you will want to check everything upstream.  In a situation with a non working project you don't want to ruin good boards by rushing and missing something obvious causing you more headaches.  Given the cost of the machine, you can expect to have to purchase some things but if you take it slowly and methodical with a copy of the schematics on hand you'll have it up and running in no time!   

[The pinballist formally known as Dean Morgan]

You need 3AG fuse of the correct amp rating, they are all usally rated at 240v.  Sell them at Jaycar etc.  Also need to know which are fast blow which are slo-blow etc

[arcadoz]

You need 3AG fuse of the correct amp rating, they are all usally rated at 240v.  Sell them at Jaycar etc.  Also need to know which are fast blow which are slo-blow etc

The voltage of the fuse  doesn't matter unless in a high voltage situation where  more insulation around the fuse wire is needed, as Dean says the Amp rating needs to be correct and the standard 3AG is fine. The ceramic fuse is most likely an old slow blow and certainly shouldn't be reading more than an Ohm or two.

[robm]

Slowly working through potential problems and did find one loose screw that may have caused the fry up but also a burnt out 7810 ic - will replace this when i can get one.  One concern i have is there is 240v going into the transformer and it (the tranny) is clearly marker 115v.  Yet the sicker on the side of the cab says it is a 220v machine.  Below are some pics of the transformer and it doesn't look to me if it has been modified in any way to suit our 240v power - but i also don't know what i'm looking for. 

I am wondering if the seller told me a story that it was working for him.... can any of you guys tell if is the right tranny for 240v?

[MartyJ]

Rob,

My Police Force (sys 11b) which I believe was an import too, states 220v on the stickers and 50 hertz.

Attached is photo of my transformer

[ajlaird]

From the look of that transformer, I assume it was the low voltage sound that burnt a bit? Looks like a short caused that.