Ilford Multigrade 500

[Leigh]

Is it possible to splice on the proper pins?

Difficult question.

If the round pin is on the power supply with a mating flat pin on the head, you could replace the head connector with a round pin connector. That is just a question of mechanical comparability, since the power supply is known to be able to handle 300W bulbs.

The main problem would be that the round-pin plug is not a standard configuration. It's a special, probably not available except by cannibalizing one from a junk head.

- Leigh

[Larry Gebhardt]

You could also see if you can find another connector layout that would fit the power supply opening and replace both connectors.

[Ginette]

Thanks for the clarification Ginette. However, the head that I acquired was marked 500 H and the lamps were marked as 300 watt but it had the 8 flat pins. I would also swear that it said it was a 600 output but that may have come from the seller. So, I don't know where this unit fits into this mess. I was unaware of this problem prior to purchasing. The seller of the light source informed me that the unit had 8 pins. The person selling me the power supply told me it had 8 pins. Neither one of these guys were familiar with system to know these finer details. I learned the hard way. Is it possible to splice on the proper pins? Some have said I could and others said no.

500H only means head, 500S is the power supply, 500C is the controller (or 500CPM), 500P is the probe.
Once again:
First generation of Ilford head is 8 flat pins and 2x 150W bulbs
Second generation of Ilford head is 8 flat pins and 2x 300W bulbs and you can found 600W power supply with the 8 flat pins receptacle.
Last generation in 7flat and 1 round pin and 2x 300W bulbs, 600w corresponding power supply have 7 flat and 1 round pin (easy to see it on closeup picture)

As you keep the latest power supply, ask the next seller to show you a picture of the head connector. To change the connector, you need to take it on another head, easier to buy a good working one instead. You will be able to find an head easily, 8 flat pins are more frequent (probably that more units was produced) but the latest connector are not rare.

[Leigh]

General information...

Here in the US, those rectangular connectors are called "Jones" plugs and receptacles.
They come in a couple of different pin sizes (current ratings) and many different pin counts.

I would need to make a bunch of measurements to determine whether the Ilford connectors are actually US versions or just look the same.

- Leigh

[Ron789]

I'd suggest you try to find a head that matches the power supply. The power supply is the weak part of the system, they tend to blow up. You can find heads, controllers etc. on eBay but I've never seen a spare power supply being offered.

[Leigh]

The power supply is the weak part of the system, they tend to blow up.

This is a universal problem with power supplies.
It has nothing to do with Ilford or the Multigrade 500 system.

The problem is with the electrolytic capacitors in the power supply.
If the supply sits unused for more than a year, these can degrade internally.
When power is applied subsequently, they fail.

The solution (before the supply has failed) is to turn the supply on for only one minute, then off.
The next day at the same time, turn it on for two minutes, then off.
On subsequent days at the same time, turn it on for twice as long each day (4, 8, 16, etc minutes)
until you reach a full hour on. This takes 7 days. At this time, it should work properly.

If it fails at any point during that process or later, it must be sent in for service.
That's simple, and should not be expensive. The capacitors are readily available.

If you have one of these systems that you're no longer using, you should turn the power supply
on for a few minutes every six months or so to avoid this problem. The controller and head need
not be connected.

- Leigh

[Ron789]

Leigh, that is great information! I did not know this. My first Multigrade 500 power supply got overheated and the transformer burnt. It actually happened while the system was powered off but the power cable was in the wall outlet. Service is no option: neither Ilford nor the supplier of the transformer can provide a replacement. So an addition to your really helpful information might be: not only switch the unit on/off but also disconnect the power cable from the wall outlet when not in use.
Luckily I got that first system free and I was able to buy a second system (including an Agfa Varioscop 60 enlarger) for 100 Euros. Since I still have the head of the first system I'm thinking of re-wiring the connector to connect it to my current system. I would then have 1 system with 2 heads, one on my Durst SM183 and one on my Focomat Iic.

[Bob Smith]

Leigh, that is great information! I did not know this. My first Multigrade 500 power supply got overheated and the transformer burnt. It actually happened while the system was powered off but the power cable was in the wall outlet. Service is no option: neither Ilford nor the supplier of the transformer can provide a replacement. So an addition to your really helpful information might be: not only switch the unit on/off but also disconnect the power cable from the wall outlet when not in use.
Luckily I got that first system free and I was able to buy a second system (including an Agfa Varioscop 60 enlarger) for 100 Euros. Since I still have the head of the first system I'm thinking of re-wiring the connector to connect it to my current system. I would then have 1 system with 2 heads, one on my Durst SM183 and one on my Focomat Iic.

Sorry this post is a wee bit late, the weak spot in the power supply is the power input socket it has a line conditioning choke attached (integral part of the power in socket). This is very easy to change and the power in socket is inexpensive, a standard off the shelf component.

Bob Smith

[thorley]

Pin 1 is the ground, if that is any help.
Attachment 187115

It would be very helpful if that diagram was a little higher resolution. I can't read it.
Thanks for posting.

[I_have_more_pixels]

Does anyone have a schematic of the control unit?
The one I have has a Intel P8035 processor.