How to determine the size in Amps of a switch?
- Thread starter --tom
- Start date
Sponsored Links
The rating is usually printed on the back of the switch, but check the rating of the appliance in case the wrong switch has been fitted.
An immersion heater is usually about 3000 Watts (3KW)
Divide by the supply voltage (usually quoted as 230 Volts)
So 3000 W / 230 V = 13.034.... Amps
That is the minimum rating of a suitable switch.
You may find switches rated at 6 Amp, 10 Amp, 20 Amp, 45 Amp etc. etc.
The first two would not be up to the job, and 45 Amp would be OTT, so I would select a 20 Amp switch.
You may also find a choice of single pole or double pole switches.
Single pole switches usually have two or three terminals, and double pole switches have four terminals.
An immersion heater is usually about 3000 Watts (3KW)
Divide by the supply voltage (usually quoted as 230 Volts)
So 3000 W / 230 V = 13.034.... Amps
That is the minimum rating of a suitable switch.
You may find switches rated at 6 Amp, 10 Amp, 20 Amp, 45 Amp etc. etc.
The first two would not be up to the job, and 45 Amp would be OTT, so I would select a 20 Amp switch.
You may also find a choice of single pole or double pole switches.
Single pole switches usually have two or three terminals, and double pole switches have four terminals.
^shouldnt the switch be rated equal or higher than that of the protective device of the circuit. And the protective device should itself should be higher than the anticipated load as you describe, but lower than the cables maximum (given the length and installation methods of the cable not the B&Q ratings).
Sponsored Links
--Tom
Is this related to the other three topics you have raised today.??
Maybe it would be easier if you just did one post with the whole story and then we can help you properly....?
Is this related to the other three topics you have raised today.??
Maybe it would be easier if you just did one post with the whole story and then we can help you properly....?
Sometimes that is a problem.
Its ok asking lots of single question relating to problem as long as they are asked in a structured order.
Theres no hard & fast rule
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
Sponsored Links
