More Confusion

[Negita43]

I see many Thai extension leads rated at max load 2400 watts and they use 3 core 0.75mm cable.

Using my back to school equation: Watts = Volts x Amps I get roughly a maximum value for amps as:

2400/240 (for ease) = 10 amps.

My understanding was that the max load for a 0.75 cable was 6 amps.

Is my ignorance showing or is there something different in Thailand?

[worgeordie]

Thai electricity is different ..... according to some Thai electricians*  I have talked to  ????

* did actually find a really good one once ,knew what he was doing and did it well ,

but they are rare as hens teeth ...

 

regards Worgeordie

[VocalNeal]

I'm not a manufacturer of cable.

It depends a lot on the construction and materials of the cable. Japanese info ranges from 7A to 15A depending on cable construction. Then there is usage. 

Unless you intend to plug in your shower heater, most domestic users will be less than, say, 1500W. So nearer to the 7A end of the scale. 

[xylophone]

17 minutes ago, worgeordie said:

Thai electricity is different ..... according to some Thai electricians*  I have talked to  ????

* did actually find a really good one once ,knew what he was doing and did it well ,

but they are rare as hens teeth ...

 

regards Worgeordie

Yes I've had that very same thing said to me before by a Thai "electrician" but he said that Thai electricity doesn't need an earth! 

 

This when I was helping a Thai lady I know,  with her restaurant and trying to install a water heater in the bathroom.....obviously I took no notice of him and ran a separate earth in the ceiling and down to an earthing rod just outside, and whilst I was at it I ran an earth to the socket outlets in the kitchen, because staff were getting "tingles" from a couple of the appliances. 
 

[Kwasaki]

Make up your own if you no happy. 

 

[OneMoreFarang]

It also depends on the length of the cable.

I don't know the exact rules and regulations, but a short distance with a little cable is a lot more acceptable than a long cable of the same size.

[Crossy]

3 hours ago, Negita43 said:

I see many Thai extension leads rated at max load 2400 watts and they use 3 core 0.75mm cable.

Using my back to school equation: Watts = Volts x Amps I get roughly a maximum value for amps as:

2400/240 (for ease) = 10 amps.

My understanding was that the max load for a 0.75 cable was 6 amps.

Is my ignorance showing or is there something different in Thailand?

 

Nothing awry with your understanding, Bangkok Cable 0.75mm² flex is indeed rated at 6A (in free air - coil it and all bets are off). But do note that our 1,800W (about 8A at 220V) kettle has 0.75mm² flex, it definitely gets warm but no real hazard unless you have a million Brits needing a brew.

 

The extension manufacturers definitely play fast-n-loose with their cable specs, but in reality, you're not going to be hooking your portable heater or welder up to it. Are you?

 

If you want a "proper" 16A extension cord it's easy enough to get the requisite 1.5mm² 3-core along with 3-pin plugs and traily outlets in order to make up your own.

 

[sometimewoodworker]

50 minutes ago, Crossy said:

If you want a "proper" 16A extension cord it's easy enough to get the requisite 1.5mm² 3-core along with 3-pin plugs and traily outlets in order to make up your own.

So does that mean that my extension is not a "proper" one ???? 

[Kwasaki]

56 minutes ago, Crossy said:

 

Nothing awry with your understanding, Bangkok Cable 0.75mm² flex is indeed rated at 6A (in free air - coil it and all bets are off). But do note that our 1,800W (about 8A at 220V) kettle has 0.75mm² flex, it definitely gets warm but no real hazard unless you have a million Brits needing a brew.

 

The extension manufacturers definitely play fast-n-loose with their cable specs, but in reality, you're not going to be hooking your portable heater or welder up to it. Are you?

 

If you want a "proper" 16A extension cord it's easy enough to get the requisite 1.5mm² 3-core along with 3-pin plugs and traily outlets in order to make up your own.

 

I luv the welder bit, that's cool so to speak. ????????????

[dddave]

 My condo building just had a thankfully minor fire in a unit.  It was caused by a rice cooker left unattended using a 7-11 style extension cord.  The outlet portion of the extension cord first melted, then set fire to a rug is was sitting on.  A lot of smoke but caught before major flames erupted.  Good thing a neighbor had a sharp nose because no smoke alarms were tripped.

Now signs in all the lifts warning about substandard extension cords...like there was any standard in the first place.

I use all industrial grade ex. cords I buy at Thai Watsadu.

[Kwasaki]

3 minutes ago, dddave said:

 My condo building just had a thankfully minor fire in a unit.  It was caused by a rice cooker left unattended using a 7-11 style extension cord.  The outlet portion of the extension cord first melted, then set fire to a rug is was sitting on.  A lot of smoke but caught before major flames erupted.  Good thing a neighbor had a sharp nose because no smoke alarms were tripped.

Now signs in all the lifts warning about substandard extension cords...like there was any standard in the first place.

I use all industrial grade ex. cords I buy at Thai Watsadu.

Something left unattended switched on, powered on an extension cord and No-one bothering to check smoke alarms is a problem. 

[goloeilmanz]

Your calculation is correct that a 2400 watt load on a 240 volt circuit would result in a current of about 10 amps. However, your understanding that the maximum load for a 0.75 mm cable is 6 amps is also correct. It is not safe to use a 0.75 mm cable to carry a current of 10 amps because it is not rated for that amount of current.

 

There are a few possible explanations for why you are seeing extension leads in Thailand rated for a higher load than the cable is capable of safely carrying:

 

- The extension leads may not actually be rated for a load of 2400 watts. It is possible that the rating is incorrect or that the extension leads are not actually tested and rated for the load they claim to be able to handle. It is also possible that the extension lead you are seeing is incorrectly labeled. 

- The extension leads may be intended for use in a different type of electrical system. In some countries, the voltage of the electrical system is lower than it is in Thailand, so a 0.75 mm cable may be rated for a higher load.

- The extension leads may be intended for use in a specific type of application where the load is not continuous. For example, they may be intended for use with tools or appliances that have a high starting current but a lower running current. In this case, the extension lead may be able to safely handle the high starting current for a short period of time without overheating.

[Negita43]

Welder NO - life support system YES????

Seriously though I've looked on Lazada but I'm not clear about the ratings the suppliers give

Does anyone know a reliable Lazada supplier of 1.5mm cable in short lengths I need about 3 meters (I did try to look at buying an extension lead and just cutting the cable out but they are few and far between and very expensive.

[simon43]

[quote]

but in reality, you're not going to be hooking your portable heater or welder up to it. 

[/quote]

 

My incompetent Thai brother-in-law wired up his arc-welder to the temporary electricity supply when I was building a small hotel in Phuket many years ago.  I was surprised when he called me late one evening shouting 'Fai Mai!' (fire!). Indeed, when I raced to the building site, he had managed to create so much heat in the wires that he had set the plastic box housing the electricity connection alight, as well as the wooden pole that it was fixed to.... Nice fire!

 

Having ascertained that there was no risk of electric shock (the electricity company wires had burnt away about 3 metres above the box), I went back to bed and left him to explain to the electricity company next day what he had done!

[Negita43]

1 hour ago, simon43 said:

[quote]

but in reality, you're not going to be hooking your portable heater or welder up to it. 

[/quote]

 

My incompetent Thai brother-in-law wired up his arc-welder to the temporary electricity supply when I was building a small hotel in Phuket many years ago.  I was surprised when he called me late one evening shouting 'Fai Mai!' (fire!). Indeed, when I raced to the building site, he had managed to create so much heat in the wires that he had set the plastic box housing the electricity connection alight, as well as the wooden pole that it was fixed to.... Nice fire!

 

Having ascertained that there was no risk of electric shock (the electricity company wires had burnt away about 3 metres above the box), I went back to bed and left him to explain to the electricity company next day what he had done!

Thanks for reminding me. The 3 pictures show what happened when I was building my house - well when Thai builders were building my house to be exact!

[sometimewoodworker]

2 hours ago, Negita43 said:

Welder NO - life support system YES????

Seriously though I've looked on Lazada but I'm not clear about the ratings the suppliers give

Does anyone know a reliable Lazada supplier of 1.5mm cable in short lengths I need about 3 meters (I did try to look at buying an extension lead and just cutting the cable out but they are few and far between and very expensive.

I have a supply and any actual electrical supply shop will have it, our local (well 50km away) supplier has it. But you haven’t bothered to complete your profile so I’ve no idea where you are located.

[Crossy]

13 hours ago, Negita43 said:

Welder NO - life support system YES????

Seriously though I've looked on Lazada but I'm not clear about the ratings the suppliers give

Does anyone know a reliable Lazada supplier of 1.5mm cable in short lengths I need about 3 meters (I did try to look at buying an extension lead and just cutting the cable out but they are few and far between and very expensive.

 

https://www.lazada.co.th/products/vct-2x05-2x1-2x15-2x25-3x15-3x25-pks-i4101713175-s16031798046.html?

 

Order 3 x 1.5 by the metre.