Timer press-switch rated 400w for 350w shower pump?

[Jon Parker]

Obviously 350w is under 400w but when the pump spins up could it surge instantaneously past 400w, and if so will it fry the switch?

Kind regards Jon

[Andy Burns]

I wouldn't have expected it to be rated for inductive loads, the Amazon details says that it isn't, but one of the Q&A on Amazon is from someone who has done just that

The Varilight website can be a bit difficult to find stuff, I think this applies, which says no

[harryagain]

Yes. The rating is for a resistive (heating or filiment light bulbs). Conventionally, if you sees a switch rated say 10aX this means inductive loads such as fluorescent lights are OK for ten amps. Typically for a motor (inductive load) the rating is half what it would carry as a resistive (heating) load.

You could make things work by wiring in a relay.

[meow2222]

Motors & filament lamps both take large startup current surges, the latter more so.

NT

[Andrew Gabriel]

Look for an immersion heater timer - you can get ones which do 15, 30, 60,

120 mins depending how many times you press the button, and they will have a relay switching the load.

[Andy Burns]

I suspect the O/P wants to restrict showers to shorter durations than that ...

[Jon Parker]

Cheers for that, was not aware of inductive vs resistive.

How about this one?

which is rated at 20A resistive and 6A inductive.

6A at 240v = 1440W so this should be ample for a 350W pump.

Regards Jon

[Andy Burns]

Looks OK rating wise, but 15 minute minimum run time?

[meow2222]

Relays are far more reliable than triacs in practice in these sort of apps.

FWIW a 350w pump is most likely over 400VA.

NT

[Jon Parker]

Yep, that's fine.

We have a shower pump which has a tendency to start itself up for the briefest of moments after 3-4 hours of switch off, so with this I'll set it to 30 mins, press it, shower, then in 30 mins the pump supply will be cut off and no spontaneous startup.

The pump isn't leaking, and the plmbing is good. I've checked all that :-)

Jon

[Andy Burns]

Ah, I was imagining a teenage child using all the water was the problem

Flow switch/sensor on a hair trigger?

[Jon Parker]

Looks that way. It sort judders as if it's trying to start up, then the bac k-pressure turns it off again. It's a pain in the arse frankly but there ar e no shut-offs with which to isolate the pump so this is a quick workaround until such time as I can afford to do it properly.

Jon