Sciencemadness Discussion Board

Powering a 2400w hotplate?

Mesa - 26-9-2013 at 21:08

Hi, I recently recieved a hotplate that was formerly used in an industrial lab. All attempts to identify it have failed, as the logo on it(selby) doesn't seem to belong to any company manufacturing hotplates.

The hotplate itself was still being used in the plant up until the day before I got it, however when attempting to use it at home, it will switch on for 5 minutes, then blow the circuit breaker for the mains. Given that I can't identify the specific model of hotplate, I can't find any technical specifications other than the wattage(which is displayed on the back.)

Short of getting a larger fuse for the house mains, is there any way I can get this plate working at home?

violet sin - 26-9-2013 at 22:53

what voltage does it take? are you in Europe standard or US standard region? this would be good information to have.

b/c most US wall outlets are 120V( give or take a little) on a 20A breaker. if you take the wattage divided by supply voltage ya get the draw in amps. so 2400W/120V = 20A. so if this is on standard US wall outlet you see why it trips the breaker. but if instead it is on 220V US / 230 Europe. I have no clue why it's tripping the breaker.

I was gonna suggest a variac but one capable of dealing with that many amps is nice and pricey. though like I said if it's 220-230V a different creature with potentially different malfunction and cure. 2400W/220V = 10.9A draw and most 220V US breakers are at least 20A(google images shows a 15A version though). so it shouldn't be popping a breaker. the dryer or range is some times 50A (only socket in the house that would run my stick welder).

heavy duty dimmer might work. a current limiting resistor in the form of another smaller heater element could work, though if unused wasteful. there are ways for sure, but I don't feel comfortable in my ability to suggest or describe a safe approach to give advice here. don't wanna cause a fire or get anyone shocked. I'm sure some one else here can possibly help with a little more info.

-Violet Sin-

Organikum - 27-9-2013 at 01:29

These dimmers are cheap and work well, tried and true.
They use a high rated STC TRIAC so no surprise. Regulate from zero to full.

Beware of the little brother with about 2000W which is big shit, regulates only from 20% up and loves to disintegrate for no reason. No surprise the TRIAC used has its numbers sanded away.....

/ORG

[Edited on 27-9-2013 by Organikum]

Mesa - 27-9-2013 at 12:43

240v, sorry to have excluded that. It is the standard for Australia and everywhere I've lived in EU so I kinda forget that other standards exist.

Organikum: Wouldn't that still draw the same amount of power from the mains, just altering the amount available to the other devices on the line? The issue I'm having is with the circuit breaker for the house, not the fuse in the hotplate itself. If it does work for this issue, that'd be fantastic!

Dr.Bob - 27-9-2013 at 13:17

If you are on 240V, then you might just be overloading that circuit, perhaps the plug you are using is also on the same circuit as the lights, an appliance, or some other item. I have an air compressor that does the same thing, it will run fine on a circuit with nothing else, but if I plug it into a plug that has any other loads on it, it will blow the breaker in a short time. So when the breaker blows, what other devices turn off, and can you simply turn them off during the use of the hotplate?

Mesa - 27-9-2013 at 13:34

Quote: Originally posted by Dr.Bob  
If you are on 240V, then you might just be overloading that circuit, perhaps the plug you are using is also on the same circuit as the lights, an appliance, or some other item. I have an air compressor that does the same thing, it will run fine on a circuit with nothing else, but if I plug it into a plug that has any other loads on it, it will blow the breaker in a short time. So when the breaker blows, what other devices turn off, and can you simply turn them off during the use of the hotplate?


Every other device in the house turns off. My 2.5hp compressor runs fine off the same plug.

Dariusrussell - 27-9-2013 at 17:39

Ok so your hotplate is pulling roughly 10A from a 240V circuit (I'd hope it is designed for 240V). In the US, your average breaker is between 15-20A at 120V. If you look at your breaker box it should say it on the breaker. Anyways, Dr. Bob is most likely right, if it is turning other things off, then you are overloading the circuit. I find it odd that your 2.5 hp compressor doesn't blow the circuit but it draw around 7A at 240, which 3A could make a difference.

My solution would be to find a different plug on a different circuit with considerably less on it, and use that. Or you'll just have to unplug tons of stuff to use it.
Awesome find though, it must heat stuff up reallllly fast!

Organikum - 28-9-2013 at 02:09

If you turn it full open then it might still trigger the circuit breaker but 2400W is overkill anyways, just put a stopper at about 75% on the knob and thats that.