Fridges, freezers and powerboards....

Forums › Home Workshop DIY › Fridges, freezers and powerboards....

kiwifidget

"Cookie"
3423 posts

Uber Geek

Lifetime subscriber

#281243 7-Feb-2021 15:48

I have a fridge, and a freezer next to each other, each plugged into the two sockets of a dual power outlet.

I would like to plug something else in there, so was wondering if it was a good idea to run one of the appliances off a powerboard to get an extra outlet?

The thing I want to plug in is a smartphone that can tell me when that couple of outlets lose power.

Delete cookies?! Are you insane?!

1 | 2 | 3

1524 posts

Uber Geek

#2649017 7-Feb-2021 16:08

Is there another socket that is on the same fuse you could use instead?

kiwifidget

"Cookie"
3423 posts

Uber Geek

Lifetime subscriber

#2649019 7-Feb-2021 16:14

I don't know.

Would I need an electrician to tell me which other outlets are on the same fuse?

Delete cookies?! Are you insane?!

Fred99

13684 posts

Uber Geek

#2649032 7-Feb-2021 16:56

kiwifidget:

I don't know.

Would I need an electrician to tell me which other outlets are on the same fuse?

Check other outlets to see which other ones aren't working by plugging in a lamp or whatever. Turn the breaker back on just to double check.

Next job after identifying that is to go around the house and reset clocks in all the annoying devices that stop or reset time when the power's been disconnected.

timmmay

20580 posts

Uber Geek

Trusted

Lifetime subscriber

#2649208 7-Feb-2021 20:44

Why would the outlets lose power? If they do then get an electrician in to fix it, rather than plugging appliances into a multibox. IMHO.

richms

28187 posts

Uber Geek

Trusted

Lifetime subscriber

#2649227 7-Feb-2021 21:40

I have tripping issues in the garage here with the old dinosaur whiteware with direct drive ac motors, inside with the newer ones with inverters and never a problem.

Richard rich.ms

elpenguino

3424 posts

Uber Geek

#2649255 7-Feb-2021 23:35

In your situation I wouldnt use a powerboard cos I hate the clutter. If you only want one more device, consider replacing one of the appliance plugs with a 'tapon'.

It's one of those mains plugs that has a socket on the back of it.

Can be approx $25 if you buy a new one but are also found on many old appliances if you want to re-use one.

Most of the posters in this thread are just like chimpanzees on MDMA, full of feelings of bonhomie, joy, and optimism. Fred99 8/4/21

fe31nz

1232 posts

Uber Geek

#2649268 8-Feb-2021 00:28

The basic rule is that each socket is only rated to supply a maximum of 10 amps. So you need to check the specifications for each device you want plugged into one socket and make sure the total is not more than 10 amps. If it is less, then you can use a plug board or double plug or tapon to have them connected to the same socket. Be conservative - if the total current ratings are close to 10 amps, then avoid running them on the same socket. It also pays to check when they are all running if the socket or wiring is getting hot. If so, reduce the load. Electricity is dangerous - always be careful.

A further complication is that some devices (such as fridges and freezers) can have a large inrush current for a short time whenever their motor turns on. The inrush current can briefly exceed the rating of the socket safely, but if you have two such devices on one socket and both have their motors turn on at the same time, it can cause a dangerous overload (ie overheating = fire risk). And it can possibly blow the fuse or trip the breaker. But the latter problem also would happen if the two devices were on two different sockets on the same circuit.

You also need to check the total load on the circuit. To do that, you need to know which sockets are connected to which fuse or circuit breaker. You can find out by using a portable lamp to plug into sockets and then turning off the breaker or pulling the fuse to see if the lamp goes off. If you have fuses, it is best to turn off the main switch before pulling them out, as there is an electrocution hazard if you pull them out with the power on. I always do this when I move into a new place as it is best done before you have lots of things plugged in and working. I make a list of what sockets are connected to what circuits and print a copy to put next to the switchboard. I do the same for the lighting circuits also. If wiring changes are done later, I update the list.

Once you know what sockets are on the circuit you are working with, then you need to find the specifications for all the devices plugged into that circuit and add them up so that you can compare them to the rating of the fuse or circuit breaker on that circuit. Circuits with sockets on them are typically rated at 10, 15 or 20 amps, but almost always will have enough sockets on the circuit that if you put a 10 amp load on each socket, you will exceed the rating of the circuit. So each time you plug in a new device, you need to think about what is also on the circuit and whether you have just created a potential overload.

A typical scenario for a problem like this is an old house with a 10 amp circuit. It already has a clothes drier on that circuit, which is typically a 10 amp load and uses the entire maximum load of the circuit. But the circuit has two other sockets on it, and someone plugs a big TV into one of them, which is in another room. The TV uses say 230 watts which is a 1 amp load at 230 volts. So now whenever both the TV and drier are on, the circuit is 10% overloaded. But the house is old and the wiring on the circuit is a bit degraded - its breaker does not trip on a 10% overload. The wiring gets very hot. And then one day months later a fire starts in a section of that circuit where the wire is most degraded and it was getting hottest.

Sharesies

Trade NZ and US shares and funds with Sharesies (affiliate link).

kiwifidget

"Cookie"
3423 posts

Uber Geek

Lifetime subscriber

#2649272 8-Feb-2021 07:18

So yes, I have tripping issues which take out the fridge and the freezer in the garage.

They are not super old, somewhere between 10-20 years.

Its an RCD which usually trips so it also takes out about a third of the house as well.

Its a modernish switchboard with flippy switches.

Whatever the cause, until it is identified and rectified, I would like to know when the freezer loses power.

It is always guaranteed to happen when we are away.

In the garage I have a couple of RPis and a NAS connected to an APC UPS.

I did find an article on how to setup apcupsd to do power outage alerts but I didnt get far in the instructions before I got "command not found" responses.

Then I read about smartphone apps that can do a similar thing if they are plugged in to their charger.

I hadnt thought of a tap-on plug.

The fridge and freezer probably have hard wired power cords, but would a tap-on extension cord work?

Tap-on ext into socket, fridge or freezer into tap-on, smartphone in to other end of ext-cord?

All the computery stuff sits behind UPSes, does this eliminate them from being the cause?

I can see that I will need to do an electrical audit of all appliances and how they connect back to the switchboard.

Fun times 😀

Delete cookies?! Are you insane?!

timmmay

20580 posts

Uber Geek

Trusted

Lifetime subscriber

#2649273 8-Feb-2021 08:04

fe31nz:

The basic rule is that each socket is only rated to supply a maximum of 10 amps. So you need to check the specifications for each device you want plugged into one socket and make sure the total is not more than 10 amps. If it is less, then you can use a plug board or double plug or tapon to have them connected to the same socket. Be conservative - if the total current ratings are close to 10 amps, then avoid running them on the same socket. It also pays to check when they are all running if the socket or wiring is getting hot. If so, reduce the load. Electricity is dangerous - always be careful.

In many cases the 10A rating is a total for all the plugs in an outlet, rather than for each outlet. For example, a wall plate with two plugs can supply 10A total, not 10A per socket. This can vary.

Fred99

13684 posts

Uber Geek

#2649276 8-Feb-2021 08:40

kiwifidget:

Its an RCD which usually trips so it also takes out about a third of the house as well.

Its a modernish switchboard with flippy switches.

You probably do need a sparky to check things out:

Check that the RCD is working properly, is the correct type and within spec, that the circuit is OK, and check the fridge and freezer (and other possible culprits on the circuit).

The latter (checking the fridge and freezer) may not be easy to check, there seem to be issues/faults with some fridge/freezers with a faulty heater element used for auto defrosting tripping RCDs, intermittent (only tripping the RCD is some conditions, when there's ice build-up etc) but testing okay in normal use. Power is only going to the faulty element when the defrost cycle is active, that trips the RCD. Or it could be a different intermittent problem with the fridges. If you google the brand/model of fridge and "RCD tripping" it might lead to clues as to what the problem is.

Bung

6487 posts

Uber Geek

Subscriber

#2649278 8-Feb-2021 08:49

kiwifidget:
So yes, I have tripping issues which take out the fridge and the freezer in the garage.

They are not super old, somewhere between 10-20 years.

Its an RCD which usually trips so it also takes out about a third of the house as well.

Its a modernish switchboard with flippy switches.

<

Write out 100 times "Flippy switches are circuit breakers."

If it's an RCD tripping and it takes out a third of the house there must be plenty of sockets your phone could be plugged into.

The defrost elements in older fridges are frequent causes of RCD nuisance tripping. Get the fridge tested.

gzt

17134 posts

Uber Geek

Lifetime subscriber

#2649279 8-Feb-2021 08:53

Manual defrosting before you go away could be an option assuming space to swap to.

I wonder if putting an RCD on each appliance could narrow down the culprit.