PID keeps blowing fuses...

[Beagle333]

I was making several loads of boolits today and about every 5th ovenload, I would blow the fuse in my PID. It is a 10A fuse. Any of you 'lectric folks know if maybe running both elements of my convection oven through it is taking more than 10A? It must not be much more, because it'll bake a few loads, then blow the fuse again. I know that the extension cord gets pretty warm. (there's no outlet nearby where I spray and bake.)
The fan and light are on a separate line.

[Hannibal]

Do you know the wattage of your oven?

[Yodogsandman]

Why not replace your fuses with 15 amp, that should cover you up to 1500 Watts. That is, if your internal wiring in your PID can handle 15 amps.

[retread]

The SSR is carrying the work load. The 10 amp fuse is protecting the PID. I would NOT change to a 15 amp fuse! If you are using an extension cord it my be too small of gauge wire. It should be at least 12 gauge.

[gpidaho]

dBeagle333: Extension cords should never be loaded heavy enough to make them warm. Whatever is on the far end is taking an overload beating. Wish we were neighbors as I have spider boxes and heavy cords enough for us both.(retired carpenter) For the sake of the equipment and safety Don't overload the cord, it may be worth while to wire a conduit circuit out to your work area. GP

[Mike W1]

15 amp is good for #14 I believe and 20 amp for #12

You lose some capacity with a long extension cord. Even the outlet itself can make a difference. Had a #12 wired circuit for my air compressor with 20 amp breaker. But with it having a 15A socket it'd pop the breaker sometimes. Got a better 20A socket and end of problem.

[Beagle333]

I probably do need to just get somebody to run a box out there. It was a 50' 14ga cord. I figured it was overloaded a bit, since it was getting warm, but I didn't know it would work the PID any harder though. I just figured it wouldn't run the convection oven at 100% power. As long as it got to 400°, I didn't care how long it took to get there. I don't know much about ac usage.

I don't know the wattage of the oven. I'd have to go look again.

edit: It's 1500W. Hmmm.... so that would be what?.... 13.6amps?

[Hannibal]

The SSR is carrying the work load. The 10 amp fuse is protecting the PID. I would NOT change to a 15 amp fuse! If you are using an extension cord it my be too small of gauge wire. It should be at least 12 gauge.

That depends on how the person who wired up the controller wired it. Ideally, there would be 2 fuses. One for the PID, SSR and control wiring of 2 amps or so, and a second in the line side of the SSR. The size of this fuse would need to be determined by the size of the wire used in the SSR circuit and the rating of the SSR. The extension cord is not helping at all in any case, and should be eliminated (ideally) or replaced with at least a 14 gauge cord. Might even need to be a 12 gauge cord depending on the length of the cord and the wattage of the oven. No way of knowing for sure without more specifics.

[Hannibal]

I probably do need to just get somebody to run a box out there. It was a 50' 14ga cord. I figured it was overloaded a bit, since it was getting warm, but I didn't know it would work the PID any harder though. I just figured it wouldn't run the convection oven at 100% power. As long as it got to 400°, I didn't care how long it took to get there. I don't know much about ac usage.


I don't know the wattage of the oven. I'd have to go look again.

edit: It's 1500W.

Ah. That's going to draw too many amps for a 10 amp fuse. Especially on a 50' cord. You need to upgrade your service to your work area and go to a larger fuse. As to the size of the fuse, the person who built your controller should know what components were used. I suggest contacting them for a recommendation. I would not simply install a larger fuse without knowing your controller is set up to handle a load of that size.

Hope this helps.

[Beagle333]

Well, I build it. This is how it's wired. But it probably does need a service ran out to the work area. I gotta work on that. I guess I'll suspend baking until I can get some more power out to the baking area. Thanks for the replies!

[mongoose33]

Do you have a generator? Might be able to run the oven off that for the few hours you need it.

And yes, get service run out to your work area. Maybe you can find an electrician who shoots who will do some trading with you. You could teach him/her how to cast and PC!

[Beagle333]

But wait..... even if I do get the 110 right to the table.... the PID still only has a 10A fuse, and the oven wants 1500W. Hmmmm......


I got this SSR in it.... why wouldn't it handle a 15A fuse?

[Hannibal]

SSR is good. What gauge wire / power cord did you use?

[Beagle333]

It was a 50 foot 14 ga.

[bangerjim]

rough estimate:

10A = 1000 watts
15A = 1500 watts

You are exceeding the 10A capacity. Simple.

Running smaller wire will not blow a fuse. Smaller gauge would just starve the instrument of it's needed amperage and lower the available voltage.

You should be using 12gauge. Period. (not a shotgun!!!!) All outlets in a standard home are wired with 12ga copper romex. Lighting circuits are normally only 14ga copper romex.

banger

[Hannibal]

It was a 50 foot 14 ga.

No, I mean what gauge wire is the short power cord that you wired your controller with and what gauge wire did you use internally between the SSR and terminal board? Needs to be at least 14 gauge. You can get away with that internally. We'd have to go thru a year's worth of electrical theory to explain why the internal wiring can be 14 gauge but if you plug it into a 50' extension cord, the extension cord has to be 12 gauge.

[Beagle333]

Running smaller wire will not blow a fuse. Smaller gauge would just starve the instrument of it's needed amperage and lower the available voltage.

That's what I was thinking. The smaller wire was a problem, but not the problem. I need more power and a bigger fuse.

[Beagle333]

Yes, Expanman.... all internal wires are solid copper 14 ga.
The power cords (plugs) coming into and out of the PID are 12 ga.

[Beagle333]

I had initially wired up the insides with lamp cord, but somebody told me that was only 18ga and good for 13amps and I would one day want more out of it.

[Hannibal]

Then based on what you have told me, you can safely install a 15 amp fuse. However, DO NOT use a 50', 14 gauge cord. Have someone qualified run service to your work area or use your generator if it's rated for 1500 watts or more. You could possibly use a 50' 12 gauge cord, but those don't come cheap these days.

Hope this helps.