Help me before I cook myself

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xpd

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#265571 28-Jan-2020 14:31

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Even though I've been a home owner for.... 15 years ?.. I've never actually had to do much around the homes, especially when it comes to electrical stuff.

But now I've got a bunch of small things that I'd like to get sorted but have this small "fear" I guess, of electricity ;) Too many zaps when younger playing with stuff I shouldn't have been I guess....

Anyway, I need to replace the sensor lights, test a floodlight, and check if some outdoor cabling is live.

1) Sensor lights - take it I can just disconnect existing and wire up same as current set - would I need to turn off mains ?

2) Floodlight - has never worked, but I'm not sure if its the bulb, unit, or cabling at fault. Not sure if I can get into the unit (not taken a good look at it yet) so lets assume I cant - only thing to check is the power to it. Do I just cut/remove the power to it (turn off mains before doing so ?) , and get a multimeter onto it ?

3) Best way of checking if cable is live ? The cable is one I found in the garden, its end sticking up and the rest runs underground, no idea where it goes/came from.

One of these tester units ? https://www.bunnings.co.nz/deta-electronic-multi-function-tester_p00270066

Which leads onto another thing...... haven't touched a multimeter since my DSE Funway kit days, and cant for life of me remember anything about them settings wise :D Looking at getting one of these - https://www.bunnings.co.nz/kincrome-digital-multi-meter-08101_p00526176

What would I need to set it to for use with home power cabling etc ?

Geek yes, sparky no.

TIA :)

XPD / Gavin / DemiseNZ

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#2408235 28-Jan-2020 14:37

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Q: What's black and crispy and hangs from the ceiling?

A: An amateur electrician.

I'd suggest making a list of all these, and any other little electrical jobs, and get a pro in for a quick visit to take care of them all...

wellygary

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#2408248 28-Jan-2020 14:52

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As above, If you don't feel confident, get a professional in.....

A little knowledge can be a very dangerous thing... especially with electricity...

networkn

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#2408258 28-Jan-2020 15:05

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I am with the other two, if you have doubts, the potential for getting it wrong and putting your life or the life of your family at risk isn't worth the saving of probably < $300.

vexxxboy

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#2408261 28-Jan-2020 15:12

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rule of thumb in my house, i dont do any work without turning the mains off at the switch board , if i need the mains on to do the work them i call in an electrician, dont mess around.

Common sense is not as common as you think.

networkn

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#2408263 28-Jan-2020 15:14

vexxxboy:

rule of thumb in my house, i dont do any work without turning the mains off at the switch board , if i need the mains on to do the work them i call in an electrician, dont mess around.

This!

tripper1000

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#2408266 28-Jan-2020 15:22

Yes, turn off the mains before poking around in the wiring. If the mains is off, you can't get killed from an electric shock. Some will tell you that you don't need to turn the mains off, but this relies on turning the power off else-where (such as the circuit breaker or light switch) but given that the lights don't work, how are you to be sure that you have the correct breaker or switch? Only by testing with a multimeter, which you don't have and are rusty in the use of when you buy one.

Regarding the flood light - cutting the wiring to test it is the least preferred option: First if it was a blown bulb, then you need to reconnect the wire (extra work), 2nd under the old standards, the green wire could have been reused for phase, with false negatives when testing and potentially lethal consequences when reconnecting to a new fixture. If you look inside the existing flood light terminal cover, a re purposed earth/green will be sleeved with red sleeving warning you all bets are off re the colour coding but if you cut the cable you don't see this and could end up 1) testing the red and incorrectly presuming the cable is safe, 2) connecting a green phase wire to the chassis of the new flood-light and killing yourself.

xpd

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#2408270 28-Jan-2020 15:34

vexxxboy:

rule of thumb in my house, i dont do any work without turning the mains off at the switch board , if i need the mains on to do the work them i call in an electrician, dont mess around.

Yeah, the times I have done anything, Ive turned off the mains :)

XPD / Gavin / DemiseNZ

xpd

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#2408271 28-Jan-2020 15:35

Thanks all so far, think I'll have to become friends with a sparky ;)

Any sparkies need a friend ? ;)

XPD / Gavin / DemiseNZ

hsvhel

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#2408278 28-Jan-2020 15:47

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I could use another "friend" i can send invoices to, will that work for you?😉

sen8or

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#2408288 28-Jan-2020 16:06

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you might have to release the moths from your wallet and buy a friend....

neb

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#2408330 28-Jan-2020 17:45

tripper1000:
Yes, turn off the mains before poking around in the wiring. If the mains is off, you can't get killed from an electric shock. Some will tell you that you don't need to turn the mains off, but this relies on turning the power off else-where (such as the circuit breaker or light switch) but given that the lights don't work, how are you to be sure that you have the correct breaker or switch?

Yeah, see this thread. Took 1-2 hours of tracing circuits (with the right equipment, most of the delay was due to having to shut down devices cleanly and checking for safety) to figure it out. OK, it's obvious in hindsight but when you assume the problem is caused by randomly-connected house wiring, which is usually the case here, it takes awhile to track things down.

Bung

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#2408352 28-Jan-2020 19:07

neb: Yeah, see this thread. Took 1-2 hours of tracing circuits (with the right equipment, most of the delay was due to having to shut down devices cleanly and checking for safety) to figure it out. OK, it's obvious in hindsight but when you assume the problem is caused by randomly-connected house wiring, which is usually the case here, it takes awhile to track things down.

Did figuring it out include why as well as how?

neb

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#2408353 28-Jan-2020 19:17

Not just why but who, the sparkie who wired up the distribution board somehow bypassed the MCBs so only the RCD that covers the three MCBs has a function. Sorting out what's wrong in the wiring would require poking round in the distribution board which is well above my pay grade, we need to get more wiring done when we do the big rebuild so I'm leaving it until then.

richms

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#2408357 28-Jan-2020 19:32

neb: Not just why but who, the sparkie who wired up the distribution board somehow bypassed the MCBs so only the RCD that covers the three MCBs has a function. Sorting out what's wrong in the wiring would require poking round in the distribution board which is well above my pay grade, we need to get more wiring done when we do the big rebuild so I'm leaving it until then.

So there is potentially no over current protection on those circuits at the moment? Sounds like that "sparky" needs dobbing in to worksafe for doing a giant F up.

Richard rich.ms

neb

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#2408361 28-Jan-2020 19:43

richms:
neb: Not just why but who, the sparkie who wired up the distribution board somehow bypassed the MCBs so only the RCD that covers the three MCBs has a function. Sorting out what's wrong in the wiring would require poking round in the distribution board which is well above my pay grade, we need to get more wiring done when we do the big rebuild so I'm leaving it until then.

So there is potentially no over current protection on those circuits at the moment? Sounds like that "sparky" needs dobbing in to worksafe for doing a giant F up.

Doesn't the RCD do that too, or is it a pure RCD function?

I'm also not 100% certain that that's the actual problem, I went as far as I could without pulling apart the distribution panel but it could be something else. The symptoms are that with the RCD off there's no power, with the RCD on and the MCBs on or off, doesn't matter, there's power.

The reason why I hadn't noticed it until now is that one of the three MCBs powers nothing I can identify (see "Casa de Cowboy"), the second is for a circuit that never gets turned off because there's a bunch of stuff that may get upset about power losses, and the third is for the kitchen with nothing very obvious that changes state when power is lost.

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