Dimmer ratings

[DrV]

Thinking of specifying an Anytronics 8x4A wall mount dimmer pack to supply some 1kW lanterns but strictly speaking 1kW is 4.17A at 240v and 4.4 Euroamps at 230v so would it do the job? Am I being nitpicky or just rigorous?

 

Dave

[Davethsparky]

Surely the question answers itself? A 4 amp dimmer is not suitable for a 4.17 amp load.

[dbuckley]

Depends on your mains voltage and the rating of the lamp. If they are the same you can just do the math, as a 1000W 250V lamp run on 250V will consume 4A and use 1000W.

 

That same lamp run at 240V will consume less current, and use less watts.

 

Lamps are not a constant power load!

[Brian]

A 4 amp dimmer is not suitable for a 4.17 amp load.

Absolute rubbish.

 

It's a 4% difference. The tolerance on the mains voltage is greater than that.

[TomHoward]

For our house lighting circuits we run 4x650W on 10A circuits. When we first installed them we checked the load with a clamp meter and it read around 9.5-9.8A.

 

That said, our mains voltage out here usually runs very high, often 255V+.

[timsabre]

Anytronics use components which are well over-rated anyway, it will be fine. They are designed as "1KW a channel" dimmers.

 

Now if it was a cheap Chinese dimmer pack, I would be more cautious.

[adam2]

In practice a load of 4.17 amps on a 4 amp dimmer should be fine, though for legal and liability reasons I would not actually recomend it.

 

One can overthink this sort of thing !

If the mains voltage may be more or less than than the alleged 230 volt nominal, which will influence the current used.

The lamps used may be designed for 220 volts, 230 volts or 240 volts, which will influence the current used.

The manufacture of lamps is not as precise as some believe, a 1,000 watt lamp (run at exactly the design voltage) can range from at least 975 watts to 1,025 watts.

 

Heat is the enemy of electronics, and if running equipment right at the limit/slightly over the limit, it should be in a well ventilated area to reduce the risks of failure.

 

Higher capacity dimmers would probably be more reliable in the long term.

 

After all no one worries about useing an "ultra fast boiling" electric kettle from a 13 amp socket.

Some draw 14 amps, at 240 volts, and still more at 250 volts.

[Brian]

... a 1,000 watt lamp (run at exactly the design voltage) can range from at least 975 watts to 1,025 watts....

And when cold will consume significantly more. It can take up to half a second for a stage lamp's consumption to drop to its labelled value from somewhere around 6-10 times that value.

[DrV]

One can overthink this sort of thing !

Precisely what I thought I might be doing.

 

So - I did what I should have done in the first place and just asked the manufacturer and they have confirmed that it'll be fine. I guess I knew that anyway but just wanted to hear it from the right place!

 

Dave

[dbuckley]

I should note at this point that we always have 3K of house lights on a 2.5K channel...