When I use the oven the power cuts out

[mankondang]

Our OP is still active on the forum, so he's not cooked himself.

The larger of the ovens shown above will pull about 13A, most power strips are fused at 10A, so no wonder the protection opened.

Even at 9A these things get warmer than I like, if I have to run on an extension I make up a lead, 3 x 1.5mm² flex is readily available as are decent traily sockets and 3-pin plugs.

Should be using 2.5mm2 for the wiring not 1.5mm2

Why??

Are ALL the leads on ALL your appliances 2.5mm2 ? I doubt it......

Rule of thumb, 1;5mm2 = 15 Amps, 2.5mm2 = 20 Amps........

RigPig

Think that the other guy is from country who use 110 volts supply (USA) and not 220 volts as in Thailand. So for the same power, when you half the voltage you double the current P=VxI. So if you double the current you have to increase the "cross sectional area" of the cables used. Must cost a bundle with the amount of copper etc these countries use. Good day

[mogandave]

Our OP is still active on the forum, so he's not cooked himself.

The larger of the ovens shown above will pull about 13A, most power strips are fused at 10A, so no wonder the protection opened.

Even at 9A these things get warmer than I like, if I have to run on an extension I make up a lead, 3 x 1.5mm² flex is readily available as are decent traily sockets and 3-pin plugs.

Should be using 2.5mm2 for the wiring not 1.5mm2

Why??

Are ALL the leads on ALL your appliances 2.5mm2 ? I doubt it......

Rule of thumb, 1;5mm2 = 15 Amps, 2.5mm2 = 20 Amps........

Rule of thumb for what length wire?

I'm not an electrician, but it is my understanding that the longer the wire, the greater the resistance, the greater the resistance, the lower the voltage, the lower the voltage, the greater the amperage, the greater the amperage, the bigger the wire.

If you are extending the lead on an appliance, it's a good bet the extension needs to be heavier than what came on the appliance.

I think the OP is referring to what we in the U.S. would call a toaster-oven.

[marios]

Electricity in Thailand is dangerous at the best of times. First thing to check is the EARTH. There is a good chance there is no earth.

Then check the power coming into the property, see how great the supply is.

Then throw away the regular oven and go and buy a good size and quality halogen oven. They draw low power and if you get one with a rotisserie, cook

joints of meat really well. There is one that has a kebab attachment.

I know people will say " oh but the air con draws lots of power " and they are right however that unit is outside the house.

One should indeed check the earth. It very possible that the insulation of an unused oven to fail and result int an earth fault. If there is an earth fault relay on the main board or on the power point used then the trip would be instantaneous. If there is no earth fault relay a leakage to earth may be such to create the overcurrnt condition which will trip the circuit.

In my opinion overcurrent can be caused due to 'normal' overload or by leakage to earth. (if suitable earth leakage protection not present) Both cases are dangerous with the latter being deadly.

[RichCor]

I think the OP is referring to what we in the U.S. would call a toaster-oven.

These things are 53/60/70/90 liter in capacity, but yes I would call it a toaster-oven.

[GOLDBUGGY]

that power strip is not powerful enough. I had the same problem. you have to get a power strip that will cover the watts.read on the back and make sure you get one for the watts your using, 2,200. their like 500 baht

and only use the oven in it.or one unit at a time,

Nothing to do with power, it is all about the current. Rule of thumb is 4A per Kw, so a 2Kw & 3Kw oven would be 8A & 12A respectively. Extension leads are normally rated at 10A so the 2Kw oven would be borderline at least.

One of the problems with extension leads is that they are often designed to accept a variety of plug styles. This can lead to poor contact area in many cases. With currents of this value poor contact can become a resistive load and start to generate heat. It is a degenerative process as if the temperature gets to a certain level the surface of the material starts to oxidise which increases the resistance and pushes the temperature up even more, invariably leading to the contact burning out.

Appliances of this nature should be plugged directly to the wall socket with the correct plug for the wall socket.

Yes. Very true.

The Rule is Volts x Amps = Watts. The Watts you can read from the back of your Oven. Since you can't change the Watts or the Volts, all you can change is the Amp Circuit. So for 2,800 Watts then:

220V x 15 Amp = 3,300 Watts.

With a 10 amp circuit you only get 220V x 10 amps = 2,200 Watts which trips your breaker or burns out your Extension Cord..

Your Breaker for that circuit will have a number written on it which in your case I am guessing it is 10. That means 10 Amps. You cannot and should not just replace this 10 Amp Breaker with a 15 Amp Breaker or your house wires would burn up You need to change your wiring first to 15 Amps, and then the Breaker.

[SOUTHERNSTAR]

The safety device operated so you threw it away? (twice)

What is the rating (Amps or Watts) of the oven, it will be on the back?

I would not use any kind of multi-lead with a high power device like an oven just plug it directly in to the wall, do you have a fire extinguisher?

...... OP are you shock proof ?

[gandalf12]

Our OP is still active on the forum, so he's not cooked himself.

The larger of the ovens shown above will pull about 13A, most power strips are fused at 10A, so no wonder the protection opened.

Even at 9A these things get warmer than I like, if I have to run on an extension I make up a lead, 3 x 1.5mm² flex is readily available as are decent traily sockets and 3-pin plugs.

Should be using 2.5mm2 for the wiring not 1.5mm2

Why??

Are ALL the leads on ALL your appliances 2.5mm2 ? I doubt it......

Rule of thumb, 1;5mm2 = 15 Amps, 2.5mm2 = 20 Amps........

Because for appliances such as cookers that is te standard. Read the IEE regulations 17 edition plus amendments

[RichCor]

kxcd

Ohm

Title text: More generally, with great power comes great dEnergy/dt

[RigPig]

Our OP is still active on the forum, so he's not cooked himself.

The larger of the ovens shown above will pull about 13A, most power strips are fused at 10A, so no wonder the protection opened.

Even at 9A these things get warmer than I like, if I have to run on an extension I make up a lead, 3 x 1.5mm² flex is readily available as are decent traily sockets and 3-pin plugs.

Should be using 2.5mm2 for the wiring not 1.5mm2

Why??

Are ALL the leads on ALL your appliances 2.5mm2 ? I doubt it......

Rule of thumb, 1;5mm2 = 15 Amps, 2.5mm2 = 20 Amps........

Because for appliances such as cookers that is te standard. Read the IEE regulations 17 edition plus amendments

It's a portable appliance, with it's own intragal plug and lead a short extension lead doen't need to be rated at twice it's current carrying capacity. Of course if the lead is longer than 20 metres then I guess you should consider voltage drop.......

And yes we are 220 volts in Thailand, it's not the States.....

[JHolmesJr]

This happens when you don't use the oven for a whilemoisture affects the heating element, shorting the circuit every time you switch it on.

Usually changing the element is the solution.which costs a bitthereafter be sure to run the oven on high for at least 10 minutes once a week, then two weeks then three and finally one a month as maintenance.

That's a new one,,I am a Sparky by trade and I have never heard of that one before ,Are you sure ? can you prove that?

Its happened to me before hence i know.....quite a common reason for ovens tripping in the tropics where there is lot of moisture in the air and if people dont turn on their oven for months.

Recently i also had a new oven that was tripping the power to the apt....it had its own dedicated 20A switch and the heating element was fine too.

They took it to the workshop and turns out there was a problem with internal wiring.

[sandyf]

I agree with most of what sandyf has said. Except that when he stated "Power has nothing to do with it it's about current". In fact Power (watts) is the product of the voltage/emf (volts) supplied to the outlet and is normaly 220 volts AC , single phase, in ThIland, and the current (Amps) drawn by your device. Power (in Watts) is egual to the supplied Voltage (Volts), multiplied by the drawn Current (I or A, Amps).

P = V x I, or P = V x A. So the number of amps that a large microwave like yours which I gather is rated at 2800 watts (2.8 kW) would draw a current of 2800 watts divided by 220 volts = 12.727 Amps. Much more than the 10 Amps rated by your Extension device, and probably more than the Circuit Breaker (Fuse box) rating for the socket outlets ( the white boxes) of which it may protect many.

So your extension devise was doing it's job. Do not increase the size of the fuse in it.

Do get the Circuit Breaker rating checked and consider having an individual Circuit Breaker fitted to protect only the circuit for your oven.

In a previous life I designed electrical laboratory and industrial ovens for about 10 years. The surface temperature of the element was manipulated by varying the length of the element to get the best all round performance and temperature distribution. I am not an electrician, just an electrical engineer.

As far as extension leads go, you would get the same problem with 50 watts on a 6v supply as you would with 2Kw on 220v. It is not about the watts.

[sandyf]

This happens when you don't use the oven for a whilemoisture affects the heating element, shorting the circuit every time you switch it on.

Usually changing the element is the solution.which costs a bitthereafter be sure to run the oven on high for at least 10 minutes once a week, then two weeks then three and finally one a month as maintenance.

That's a new one,,I am a Sparky by trade and I have never heard of that one before ,Are you sure ? can you prove that?

Its happened to me before hence i know.....quite a common reason for ovens tripping in the tropics where there is lot of moisture in the air and if people dont turn on their oven for months.

Recently i also had a new oven that was tripping the power to the apt....it had its own dedicated 20A switch and the heating element was fine too.

They took it to the workshop and turns out there was a problem with internal wiring.

Years ago many ovens were made using coiled resistance wire. Depending on how the element was fitted, damp insulation could cause tracking across the coil reducing the resistance and causing a hot spot on the element. The breaker would trip or the element burn out.

Modern day oven are normally fitted with a mineral insulated element which is unlikely to be affected by humidity.

[hawksway]

Ovens often need a lot of power so you will need a qualified Electrician to put in a dedicated 30 AMP breaker as the normal ones might not be able to cope with the load. Best to run the Oven from a dedicated circuit.

[Crossy]

There is some, er, interesting, advice here.

To summarise:

Our OP has a large 'toaster' oven, as a portable device this should have a regular 3-pin plug.

The biggest unit in this range is 2,800 Watts and will draw about 13A at 220V which will be fine on a normal power circuit. A dedicated circuit (or rather a second circuit for the kitchen) would be a good idea if he has other high power equipment in use at the same time.

Most traily extensions are fused at 10A = pop! Even at 10A the cheapies get very warm.

If you make up a DIY extension use 1.5mm² 3-core flex, it's rated at 15A so will be fine. As a guide read the size of the appliance flex and use that as a minimum. You'll struggle to get 3 x 2.5mm² flex into a normal Thai plug (or even a UK plug) and it's not needed in this case.

[jacko45k]

I am not sure what you mean by 'one of those 4 pronged power adaptors' as here plugs and sockets have 3 prongs and sometimes even 2. At a guess you mean an extension chord with 4 outlets and a built in circuit breaker, the type with a little red or black button perhaps.

Well first get it out of the bin as it sounds like it is under-rated for your oven but the breaker is doing its job. The fact that it happens after a few minutes suggests it is not far out, and no it does not suggest there is anything wrong with the wall socket at the other end.

These extension chords are not really good for heavy duty loads. I just checked one I use for my TV and it is rated at 10A, and another I have is rated at 13A, or let us say 2000W and 2500W respectively. What is the power rating of your oven? Likely higher as even an electric kettle could be 2000W.

Try it directly from the wall outlet, without the extension. It may well still give problems at the main breaker box, tripping one of the circuits there, particularly if you run it at the same time as another high powered device.

If you cannot position ithe oven close to the wall outlet, you may have to go shopping for a heavy duty extension chord with a higher rating. Look for a good quality item with a thick cable, and ensure it's rating is higher than the oven. (Power (Watts)=Current (Amps) x Voltage (240 here)). They sometimes rate things in amps, sometimes in Watts or kilowatts (1KW=1000W).

And don't plug an electric kettle into the same extension chord!

My apologies if I have been seemingly patronising.

Edited August 23, 2015 by jacko45k

[sandyf]

Ovens often need a lot of power so you will need a qualified Electrician to put in a dedicated 30 AMP breaker as the normal ones might not be able to cope with the load. Best to run the Oven from a dedicated circuit.

Unnecessary expense due to a lack of understanding.

If in doubt follow the manufacturers instructions.