Ask an Electrician anything...

[CheesecakeRunner]

MK1RS Bruce said:

How do you connect the cable between the consumer unit and the meter, there doesn't seem to be anyway to isolate the top of the meter to make such connections in mine.

Legitimate way is to contact your DNO and have them come and temporarily remove the fuse from the main cutout. Replace the cables, then have the DNO put the fuse back. Useful to install a switch whilst the power is off to enable you to isolate the consumer unit in the future.

Non-legitimate…. well, it’s amazing the amount of times the main fuse falls out when a sparky isn’t looking and jumps back in by itself after they’ve finished work…

[steve-V8s]

brman said:

I am also curious what equipment you have that cannot filter the noise locally?

It is mostly very sensitive radio equipment where I am trying to detect and measure fractions of microvolts. As a stating point you need a clean earth to reference the signal against, also you need a very clean incoming power supply for the measuring equipment ideally not using a switch mode supply. A good way of ditching incoming noise on the supply is a common mode choke which passes the filtered noise to ground. With PME the earth has so much noise on it that the filter actually increases the noise floor rather than reducing it. Running the equipment from batteries removes the noise but is not ideal. Other than converting the entire house, or working in the shed, the only solution I can come up with is to use a big isolation transformer so the supply is now floating with reference to the rest on the house and then connect to a local stake just to the isolated equipment.

A better solution would be to stop the import of all the horrible, cheap plug in chargers, laptop power supplies, and general junk which seem to be provided with almost everything. If your phone charger is very small and light it is almost certainly wasting a fair bit of energy making electrical noise rather than charging the phone.

[Belle427]

Why can't they install back boxes straight and securely?

[Volare]

stressfree said:

Hi, we bought a new build house and asked to install the outside socket. Socket is installed as a spur from the inside. My concern is that there is no isolating switch inside for the outside socket (water ingress or fault will be tripping an internal rcd on the same ring or someone can steal the electricity when we are not at home). Should they have installed the isolating switch or a separate rcd in the consumer unit? What is required by the regulations?

thank you

No requirements to have a separate isolator or circuit protection. To prevent nuisance tripping inside the house you can fit a socket with an integrated RCD, that will cover you for most circumstances except overloads or short circuits, it would have to have an RCBO for that, which I don't think you can get built into a socket.

[Watcher of the skies]

dundarach said:

If I have 12v's DC from a Scalextric transformer, how can I step this down inside a model to 5v's DC in a simple component say 1cm without much heat.

So that I can use 5v motors rather than 12v motors, across the power band from the standard Scalextric controllers.

Hugs kisses and thanks

I'd use a potential divider. Much simpler.

[nyt]

dundarach said:

If I have 12v's DC from a Scalextric transformer, how can I step this down inside a model to 5v's DC in a simple component say 1cm without much heat.

So that I can use 5v motors rather than 12v motors, across the power band from the standard Scalextric controllers.

Hugs kisses and thanks

Google 'Buck Converter'


https://www.ebay.co.uk/itm/283657020689?_trkparms=...

[PAT64]

Hi thanks for the topic, I wish to get a lamp or lighting installed in my attic, how much roughly would an sparky charge for this job ?

[take-good-care-of-the-forest-dewey]

944 Man said:

Why do you always park your vans directly outside the house that you're working on, on new build sites, making it impossible for HGVs to get through?

Because, like electrons, they follow the path of least resistance.

[MJNewton]

Volare said:

No requirements to have a separate isolator or circuit protection. To prevent nuisance tripping inside the house you can fit a socket with an integrated RCD

That wouldn't necessarily prevent nuisance tripping if still spurred from an RCD-protected circuit. The only way of providing discrimination between daisy-chained RCDs is to have one of them time delayed, but this then undermines the reason for having the RCD in the first place. Better to have a separate circuit with its own RCBO, if achievable. In practice however it is unlikely to be an issue and I'd just opt for a double-pole isolator to disconnect the socket when not in use.

[Jarcy]

I have halogen spot lights throughout my house. A mix of GU10 & MR16 (with individual transformers). Also fittings with G9 (some dimming) and even some G4 (non dimmed).
One room has 4 circuits, controlled by a Wise Control system ('Scene'), with dimming to both GU10 circuit and MR16. Also non dimming coloured LED on one circuit.

It's time to move to LED.
What should I get that is properly dimmable? Does each bulb require a driver? 240v or 12v? What will work with the Wise Control? How do I ensure that I get a consistent 'warm' colour throughout? Can you get a narrow beam LED GU10?

The answer might be to get a sparkie in, but that kind of goes against the grain to change a light bulb!

Many thanks!

Edited by Jarcy on Wednesday 27th October 12:48

[Last Visit]

Do these threads really exist for techical stuff? I thought it was more like 'how many times has a house wifes dressing gown come undone after her husband has gone to work' or 'have you ever priced up a job and the customer has commented that its considerably less than they imagined?'

[cwis]

Watcher of the skies said:

I'd use a potential divider. Much simpler.

Sensible!

Buck converters etc will just supply fixed 5v or whatever they are set to.... If the cars still work like they did on the old days and are powered by a variable voltage 0-12V and haven't gone digital, you will find buck converters and other voltage regulators a little binary in the throttle response department....

[dhutch]

Volare said:

stressfree said:

Hi, we bought a new build house and asked to install the outside socket. Socket is installed as a spur from the inside. My concern is that there is no isolating switch inside for the outside socket (water ingress or fault will be tripping an internal rcd on the same ring or someone can steal the electricity when we are not at home). Should they have installed the isolating switch or a separate rcd in the consumer unit? What is required by the regulations?

thank you

No requirements to have a separate isolator or circuit protection. To prevent nuisance tripping inside the house you can fit a socket with an integrated RCD, that will cover you for most circumstances except overloads or short circuits, it would have to have an RCBO for that, which I don't think you can get built into a socket.

RCD wont prevent nuisance tripping as there is no mechanism for the RCD in the socket to trip before the RCD in the house.

[LostM135idriver]

what balances out all of the electrons that come out of the socket into my TV and where do they go?

[Baldchap]

LostM135idriver said:

what balances out all of the electrons that come out of the socket into my TV and where do they go?

They basically just zoom round the circuit make magic happen like TV or light. They don't leave the circuit with the picture/light.

[dhutch]

Why would you fit MK (honeywell) when Hagar appears better and cheaper?

Socketry, switches, consumer unit. etc.

[Jarcy]

Last Visit said:

Do these threads really exist for techical stuff? I thought it was more like 'how many times has a house wifes dressing gown come undone after her husband has gone to work' or 'have you ever priced up a job and the customer has commented that its considerably less than they imagined?'

Yeap, Confessions of a Sparkie. I'll rephrase:

Much like for where in the car industry, you're now not 'allowed' to touch anything under the bonnet:
Did to the trade embrace the introduction of LED, so that homeowners can no longer change a light bulb?

[Volare]

dhutch said:

RCD wont prevent nuisance tripping as there is no mechanism for the RCD in the socket to trip before the RCD in the house.

True, it would be 50/50 as to what goes first, but its still better than nothing and easy to do.

[Cold]

Typical tradie. Promises loads, starts the job then buggers off without completing it.

[mikeveal]

take-good-care-of-the-forest-dewey said:

Because, like electrons, they follow the path of least resistance.

They follow the path of lowest impedance. Very often that's not the path of least resistance.