Auto resetting RCD? help please...

[papalazarou]

Hi guys, wonder if anybody can give me a little advice.

I work away from home and own a salt water aquarium. Although I have somebody checking on and and feeding the tank eack day the house is often empty for 24 hours. On monday my electrics tripped and I lost the power in the house. The result was the loss of all my fish and corals, costing a not inconsiderable amount of money, not to mention the time I have spent building the tank.

Someone told me there was some sort of auto resetting rcd that could be put in place that would chech the current and if all was okay reset the electrics. (My house is pretty new and the electrics have always been stable but the aquarium lights are on timer switches which I have heard can sometimes cause a spike and trip the switch)? Knowing very little about this sort of stuff I came onhere. Does this sound like a possible solution? If so, any ideas where I would get one and the costs involved? If I'm barking up the wrong tree is there anything else on the market that could safeguard my tank.

Sorry for the long post, any advice or thoughts greatly appreciated.

Shaun.

 

[High Tower]

I have never seen one, defeats the object to be fair!

 

[Marvo]

There are auto resetting RCD's but they're not very often used because they're expensive and they'll only auto reset if a miracle occurs and the earth leakage fault disappears or at least drops below the 30mA tripping threshold. See the Gewiss range, I know they have them.

 

[Doomed]

Restart

 

[tony mc]

Put the aquarium on its own circuit used only for the aquarium on a un RCD protected side of the consumer unit.
As long as certain precations are taken as per the regs this would at least take some worry out of it happening again.

 

[papalazarou]

Thanks for the replies, I can't open the link at the moment as I'm at work on the phone browser. I'll look at it and also the gewiss later though.

Putting the aquarium onto its own circuit is an option but not a direction I really want to take at the moment as the house is regularly (most days) empty for 24 hour periods.

What about some sort of battery back up in case of an electrical shutdown? Have anybody come across anthing like this? I know that you can get them for a pc so you don't use the data but I'm not sure how long one of these would last. Any device would have to be capable of running a small pump and also a 200w aquarium heater for as long as possibe.

Anybody got any thoughts on this?

Once again thanks for the replies, you're helping me at least narrow my options!

 

[papalazarou]

Put the aquarium on its own circuit used only for the aquarium on a un RCD protected side of the consumer unit.
As long as certain precations are taken as per the regs this would at least take some worry out of it happening again.

Thanks Tony, I have been looking at UPS machines and it seems most if not all of them are designed to keep a computer running for minutes rather than hours.

What kind of precautions would we be talking about here? would this be legal? also what would home insurance implications be?

Again sorry for all the questions, I am just trying to explore all options then I can see which direction I need to be going.

Shaun.

 

[Octopus]

Thanks Tony, I have been looking at UPS machines and it seems most if not all of them are designed to keep a computer running for minutes rather than hours.

What kind of precautions would we be talking about here? would this be legal? also what would home insurance implications be?

Again sorry for all the questions, I am just trying to explore all options then I can see which direction I need to be going.

Shaun.

UPS's come in different sizes - there are wizzards on the web that help you "size" them, the bigger they get the more expensive they get.....

 

[j.mawer]

Tony's idea of putting of a seperate circuit requires precautions to protect the cable. Current regulations have pretty much all wires which are buried in walls less than 5cm protected by an RCD , essentially these regs are to protect from people nailing through wire and the like (regs 522.6.6).
The alternatives include surface mounting (then its not buried!) or burying the cable with it either in an earthed conduit or using a cable with appropriate earthed metallic covering.

Now most sockets should have RCD protection as its in a domestic situation however it is permitted to not have RCD if it is for a specific piece of equipment (and it must be labelled as such regs 411.3.3b). Typically this is where something bad happens if the RCD trips e.g. a freezer defrosts or your fish die! You could always get it wired on a fused non socket outlet if you wanted which would stop someone unplugging it too!

Now as this work involves adding a new circuit it it notifiable to building control (the law). You could have to get an electrician who is in a part P scheme to do it (e.g. a member of NICEIC napit or elecsa) they will register the work with building control for you and provide an appropriate certificate (Electrical Installation Certificate). If you are tempted to DIY it then there is a procedure and a cost of around £150 they will come and inspect the work conforms to all regs so its cheaper/safer to get it done for you!
The solution perfectly legal but might not be very pretty depending on where the aquarium is with regards to the consumer unit.

 

[ian.settle1]

Thanks Tony, I have been looking at UPS machines and it seems most if not all of them are designed to keep a computer running for minutes rather than hours.

What kind of precautions would we be talking about here? would this be legal? also what would home insurance implications be?

Again sorry for all the questions, I am just trying to explore all options then I can see which direction I need to be going.

Shaun.

Most desktop UPS are designed so that should you lose power when using computer you have enough time to do a safe switch off rather than it going off straight away thus losing or corrupting data.

 

[papalazarou]

Thank you J. Mawer

A very informative and helpful post.

As it stands the tank is in my living room (which has not long been decorated) and the rcd is in the downstairs toilet (which has just been decorated)!! it sounds like I really don't want to be having new circuits put in if I can possibly help it.

Last night on a very boring night shift I was trawling the internet and racking my brains and believe I may have come across a possible solution. It is a mains power failure alarm. It has a gsm module in it for a sim card and back up battery power and it plugs into a mains socket on your circuit. In the event if power to the socket failing it dials up to 3 numbers via the mobile network and also sends an sms text alert to up to 3 phones. This would theoretically enable somebody to be round at the house within 10 mins or so and check the electrics.

Has anybody come across one of these before? They are quite pricey at around £200 but that is a lot less than the cost of a tank full of fish and coral!

 

[oldtimer]

Run a seperate circuit to your tank and get an RCBO fitted. In other words seperate the supply to your tank from the main RCDs and protect it with its own RCD/CB or RCBO this will do 2 things if one of the main RCDs trip then your tank will not be affected if your RCBO supply to the tank trips then theres no discussion you have a problem with the tank electrics.

 

[Deleted member 26818]

If you were to run a new circuit, then you might as well install it in such a manner that RCD protection is not required.
Another option might be to install a Type C RCBO, Zs permitting of course.

 

[j.mawer]

See where you are coming from with the decoration, always the way. Some surface mount trunking looks better than others e.g. semicircular or quadrant can blend in with skirting, however if the toilet is the other side of the hall from the lounge then its probably not going to look perfect! worth thinking about though as it still might be cheaper than the alternatives e.g. GSM module or dead fish.

 

[SMB]

Dig a pond and enjoy natural British aquatics?

Laugh.



Oldtimer posted the correct answer to your question I reckon.

All the best.