Which switch for a pond pump?

[HappyHippyDad]

Hello,

A friend has asked me to replace a broken 2 gang switch in her garden which works electrically but is very badly cracked. One switches her pond lights and the other her pond pump.

I am not registered yet (will be in oct hopefully!) but believe it is ok to do a like for like change? I will check out first where the feed is coming from and if not RCD protected I wont do it, I'll also check that it is suitable cable and again am not going to get into this job unless it is just a simple change.

She presently has a normal suitably IP rated switch, see below



Should I fit this or one that is specifically for pond pumps/lights, see below




The rather fancy one just above has seperate fuses for each switch. Does the switch have to be fused?

Thanks.

 

[ian.settle1]

Why not replace it with a metalclad 2-gang switch

 

[londonlec]

Why not replace it with a metalclad 2-gang switch

In the garden?

Replace like for like with an MK masterseal one

 

[Strima]

Is this equipment on it's own circuit? If they run off a spur I would be tempted to fit DP switches incase there are any earthing problems in the future, you can then at least isolate those circuits without effecting the rest of the ring.

 

[ian.settle1]

In the garden?

Replace like for like with an MK masterseal one

Misread the garden part.

 

[Guitarist]

Doesn't really matter, just as long as it's IP rated as you say. The advantage of the larger units is that it's much easier to fit the glands in without being so fiddly, though the MK masterseal range are good.
Just make sure the cable is suitable and protected with a 3A fuse as well as from mechanical damage.
Also, make sure you drill the appropriate drain hole in the bottom (usually around 3mm). Any unit which is subject to changes in temperature will end up with condensation inside, which will need a way out.

 

[Rampage]

The Blagdon switches as above are very expensive, B&Q sell something similar but much cheaper in their larger stores, it shoulda be on their website.

 

[HappyHippyDad]

Thanks all,
Yes, the masterseal look good and scewfix do a good price.

Doesn't really matter, just as long as it's IP rated as you say. The advantage of the larger units is that it's much easier to fit the glands in without being so fiddly, though the MK masterseal range are good.
Just make sure the cable is suitable and protected with a 3A fuse as well as from mechanical damage.
Also, make sure you drill the appropriate drain hole in the bottom (usually around 3mm). Any unit which is subject to changes in temperature will end up with condensation inside, which will need a way out.

I'm not too sure if you are saying 'to fuse or not to fuse' Guitarist? You said it doesn't really matter, its more to do with IP, and then suggested a 3A fuse? The MK masterseal will not have fuses and I doubt the circuit will have any other protection than the MCB (and hopefully RCD) in the CU. Should it be fused?
The lady said it is fed from somewhere in the garage, so I need to investigate further and find out exactly what is protecting it. If it is from a 6A MCB is that sufficient or does it need a FCU as well because it is outside?
I didn't realise the drain hole was for condensation, just thought about rain water, thanks..

 

[PEG]

Good call from Guitarist re; drain hole. I do a fair bit of external work,tanks,bio-filters etc and even though the good quality IP rated enclosures and swichgear can 99% exclude moisture,only a vent of sorts can release that inevitable 1% which ends up there due to temp variations.RS and a couple of other suppliers do some nice drains and filter vents which fit unused gland ports or where convienient. Otherwise,mount soundly,3mm hole as advised,little chamfer both sides,job done. Nowt more annoying than opening up a decent,suitably IP rated enclosure to find fishy rust goo because some herbert fixed box with paslode/clout/screw and gave this summers rain somewhere to go...

 

[Richard Burns]

Thanks all,

I'm not too sure if you are saying 'to fuse or not to fuse'? Should it be fused?
f it is from a 6A MCB is that sufficient or does it need a FCU as well because it is outside?

You should not need to fuse down a switch. Just replace the existing switch with a suitable outdoor switch.

 

[Guitarist]

Thanks all,
Yes, the masterseal look good and scewfix do a good price.




I'm not too sure if you are saying 'to fuse or not to fuse' Guitarist? You said it doesn't really matter, its more to do with IP, and then suggested a 3A fuse? The MK masterseal will not have fuses and I doubt the circuit will have any other protection than the MCB (and hopefully RCD) in the CU. Should it be fused?
The lady said it is fed from somewhere in the garage, so I need to investigate further and find out exactly what is protecting it. If it is from a 6A MCB is that sufficient or does it need a FCU as well because it is outside?
I didn't realise the drain hole was for condensation, just thought about rain water, thanks..

Obviously hippy, the fuse is there to protect the cable, but in the situation you will have, unless you buy a switch unit with individual fuses built-in, you will be relying on the main supply fuse to fulfil manufacturers instructions also. As most pond equipment requires a 3A fuse, then that is what I recommend you install (if not already there)
I worked as an electrical engineer in the food and drink industry for over 15 years, and trust me, I've tried all kinds of ways to keep moisture out of IP rated switchgear. It does not work, hence you will find most units actually have a special slot where the drain-hole goes. No disrespect to you new guys, but this is where apprenticeships and experience can save a customer a lot of grief down the line. All the apprentices I have trained go out into the world with a few little tricks up their sleeves