Need help fixing/understanding rotary grill

[Niels]

Hi, I got an old professional rotary grill from my butcher. The thing was realy good when he bought it. And you've not tasted chicken untill you got it from under a nice grill.

But it has a short. I messured the power cable, and with the switch full on, 0 Ohms.
I disassembled it and messured the individual components.
The 3 heating elements all gave me about 50 Ohms, wich I thought was good.
The thermostat works and doesn't have a short.
The timer is just a switch, which works fine.
There are some indicator lights and some resistors, all measure the indicated values.
The motor gives me about 5k, also not a short.

The one thing I am unsure of is the power switch. It has 3 modes, all off, and two different selections for the grills. I took the switch out and measured what it does in the 3 modes. But it makes no sence to me. It has 6 pins. In mode 1, pins 4/5 and 2/3 connect. In mode 2 nothing connects. In mode 3 pins 5/6 and 1/2 connect.

I rewired the lot the same way it was before (I took pictures, I am sure it is exactly wired as before), but this time outside the big metal casing. Again, in any of the on modes it gives a short.

I made a diagram for myself to help me understand what is wrong. But I can not figure out how the thing is supposed to work. It's been a while for me working with this kind of stuff. It's not complicated, but I just can't work it out. I even run a simulation, but nothing mutch happens and I do not understand the readings I got. I guess it's been too long for me.

Can somebody explain to me if there is something really wrong with the wireing.
And if possible, can somebody give me an alternate wireing?
I'm in the Netherlands, so I've got 240V going trough that thing. The rating is 1600W.
I made a screenshot of my diagram.

Edit: I made a quick diagram for how I would like to rewire it. Oven2.jpg. Would this work? I think the resistors where there for the indicator lights. Can I leave them out?

 

[Harald Kapp]

You haven't marked pins 1-6 on the switch, which makes it hard to decipher the workings.
It looks like in one of the modes (let's say 1) all heating elements are on, as indicated by Light 1. That would be the switch position as shown in your first diagram.

In the inverse mode (let's say 3) only the upper heating element 1 is on, Upper heating element 2 and lower heating element are off, short circuited by the switch.Indicator light 2 is on.

In the mode 2 (no connections) all heatrs are off, no indicator lights are on.

Try to locate the short by removing one element after the other from the circuit.
Finally there is a chance that the switch has an internal short.

Last not least I think the way you want to re-wire the grill is o.k.. Note, however, that the re-wired grill will operate differently from the original one. You wil have different combinations of heating elements:
- none
- lower only
- both upper only
- lower + both upper
That is different from what the original circuit does, see explanation above.

 

[Niels]

Right you are. I've added the pin numbers in the diagram oven.jpg.

Thank you for your explanation! I couldn't work out how the short works in this diagram.
I was hoping for the switch being broken. But since I didn't see how the thing worked, it was hard to figure that out for myself.

I'll replace the switch first with some other switches I have laying around. I don't have a 6 pin switch, but I'll improvise.

In using my diagram, won't that cause problems for either the motor or the heating elements? Is my idea correct that the resistors are only there for the indicator lights?

My prefered way of fixing this is indeed with my working, so I can also use only the lower element. But I am hesitant to just go ahaid and try, because I'm afraid I might burn out the motor or the heating elements.

Oh and is my math correct? There should be about 4.8A going through the heating elements and 48mA trough the motor. I want to add a fuse to the motor and one to the elements.

 

[duke37]

You have not said if there is a short with the power switch off.
Progressivley disconnect the switch and see where the short disappears.
The timer may have a short.

The motor seems to be mains driven and will not be damaged by anything you do.

 

[Niels]

There is not short when the button is in the off position.

The timer is mechanical. The motor for the rotor drives a wormscrew which in turn drives an uneven shaped keg. The keg presses 2 connectors shut, forming a connection. The timer isn't the problem.

If the problem isn't helped by replacing the switch, I'll try disconnecting the pins to find the problem.

Thank you for the advice!