Is it ok when high wattage power cables get hot?

[Paul36x]

Should power cables stay cold at all times? My shower heater cable gets warm when I use it, now I know the cable should be replaced anyway in this case but I read many posts on the internet with people saying it is normal for high wattage devices like water cookers, AC units and shower heaters to have their power cable heat up during usage. My power cables have a 70*C rating written on them.

Should you be alarmed at all times when a cable gets warm and immediately replace it? Would this be a good way to indicate whether painted over cables should be upgraded or not if you don't know their load capacity?

 

[pushrod]

Cable will often get quite warm in normal use. Current carrying capacity is calculated using formulae and tables. Aging cables can be checked by an electrician with test instruments. If the cable was professionally installed and the shower has not been upgraded to a more powerful one i would not be worried by the cable getting warm - if you are concerned get a recommendation for a good electrician and ask to have it checked.

 

[Marvo]

If a cable gets considerably warmer in a short time when under load that's a fair indication it's overloaded. I would also suggest you have it checked by an electrician.

The temperature rating on the cable shows the maximum temperature before damage occurs. The general working temperature of the cable should be a lot lower that the temperature indicated.

 

[Des 56]

Feeling cables with a finger thermometer will not give an acurate assessment of the capability of the cable to carry the load
The main concern with generating heat in a cable,is ,how is it dispersed
If the cable is routeed through insulation that traps that heat,then problems could occur,breakdown of insulation etc
If the cable is in free air,the heat is dispersed pretty effectively

 

[spsparks]

Hi You need to get this checked

 

[GStueyXR]

If you can see the temp rating of the shower, can you also see the cross sectional area of the conductors?

You should see either 6mm or 10mm!

 

[nickblake]

Problem you may find if its getting considerabley hot in free air conditions then there may be a potential problem over load etc one of my main concerns would be if the cable runs under insulation ,where the heat will be unable to dissipate this area would then be getting hotter and could potentially cause a fire check the cable size and kw rating of the shower so many shower been installed with the wrong cable size

 

[telectrix]

as previous posts, but there is warm and too warm. if in doubt, call in an electrician who will have the equipment to check the current and cable suitability, and ( if he has the test gear ) to measure the actual temperature of the cable. what may feel warm may only be normal for the loading.