Best way to wire in new GU10 fittings

Hi all,

I'd be grateful for some advice on how to wire in some new GU10 fittings. I bought these fire rated Minisun ones: https://www.amazon.co.uk/dp/B00GSPFK2O/ref=pe_3187911_185740111_TE_item

I will be removing the existing GU5.3 (MR16) fittings before starting. These fittings have a standard wiring: i.e. bulb to GU5.3 fitting to transformer to mains. The connection between the transformer and the mains uses wiring that's built into the transformer (i.e. two single wires, one each for live and neutral). The connection to the mains (which I assume is 2 core and earth) is done through a standard round junction box.

I'd like to know the best way to wire the mains to the new GU10 fittings once I've removed the transformer (and the GU5.3 fittings)

- Option 1: Is it safe to connect the mains directly into the choc box that is pre-attached to the GU10 fitting, i.e. removing the existing junction box and wiring the mains to the fitting? If I do this, the fittings are not class II, so I assume I would need to strip the mains wire sufficiently to be able to run the earth wire down to the metal body of the fitting. This doesn't seem very elegant to me, and I'm concerned that the external insulation will be gone and the choc box will only be gripping the wires themselves.

- Option 2: Would it be better to use Wago lighting connectors and a Wagobox? In which case, would I:

2A. Replace the choc box built into the GU10 fitting with a wagobox? I.e. by removing the existing junction box and then wiring both the mains and the bulb connector into the Wagobox. If so, would it matter that the wagobox was not fixed to the fitting, i.e. would this put stress on the connections? Or would it be better to attach the wagobox to the fitting, e.g. with a zip tie?

OR

2B. Use both a wagobox and the choc box on the GU10 fitting? I.e. by replacing the existing junction box with a wagobox, and then running a new wire between the wagobox and the choc box on the fitting. If so, what kind of wire would I need?

Thanks!!

Matt

in your situation i would pre-flex the new fittings each with approx. 10" of 3 core 0.75mm flex. then connect the other end of the flex into the existing round JBs. making sure all connections are good. if the fittings have an earth terminal, use it. if not just fit a single choc block to the cpc.

telectrix said:

in your situation i would pre-flex the new fittings each with approx. 10" of 3 core 0.75mm flex. then connect the other end of the flex into the existing round JBs. making sure all connections are good. if the fittings have an earth terminal, use it. if not just fit a single choc block to the cpc.

Click to expand...

he meant connector block

Pre wire your new fittings with Click flow connectors.

Easy and simple to connect up, and easy to change a fitting in future.

telectrix said:

in your situation i would pre-flex the new fittings each with approx. 10" of 3 core 0.75mm flex. then connect the other end of the flex into the existing round JBs. making sure all connections are good. if the fittings have an earth terminal, use it. if not just fit a single choc block to the cpc.

Click to expand...

Thanks very much for this advice. I take this to be similar to my option 2B, but just re-using the existing junction box instead of using a Wagobox.

If I can't get the round junction boxes through the ceiling holes to re-wire them then presumably it would be fine to switch the junction boxes with wagoboxes (or click flow connectors)?

On the cable to use, I think I heard that it's not allowed to step down the diameter of the cable in a ceiling? In which case, wouldn't I need 1.5 mm cable rather than 0.75 mm flex? Or would 0.75mm be okay?

Thanks,

Matt

p.s. I've read that the GU10 fittings do have earth/cpc terminals.

Cadgey123 said:

Pre wire your new fittings with Click flow connectors.

Easy and simple to connect up, and easy to change a fitting in future.

Click to expand...

Interesting suggestion thanks. I'd need a matching one to wire to the mains?

what you do need to ensure is that the cpc is continuous from the fuseboard to each and every downlight.

Murdoch said:

what you do need to ensure is that the cpc is continuous from the fuseboard to each and every downlight.

Click to expand...

Okay, thanks. How would I check that?

Matteo2000 said:

Okay, thanks. How would I check that?

Click to expand...

with a tester ...........

Murdoch said:

with a tester ...........

Click to expand...

Okay, something like this?
https://www.amazon.co.uk/Multimeter...19031_1_1?s=diy&ie=UTF8&qid=1508959342&sr=1-1

Matteo2000 said:

Okay, something like this?
https://www.amazon.co.uk/Multimeter...19031_1_1?s=diy&ie=UTF8&qid=1508959342&sr=1-1

Click to expand...

you would need a long lead to reach the origin of the circuit as well. something like:
Electricians R2 15m test lead extension wander lead, Megger, Fluke, metrel etc | eBay - https://www.ebay.co.uk/itm/Electricians-R2-15m-test-lead-extension-wander-lead-Megger-Fluke-metrel-etc/181393042234?hash=item2a3bde2b3a:g:U7UAAOSwU9xUQjip

Matteo2000 said:

Interesting suggestion thanks. I'd need a matching one to wire to the mains?

Click to expand...

Put male on the fitting and female on the mains wires.

Male pins goes out
Female pins goes inwards

Like humans

Those quick flow connectors save alot of faffing about, but thought why the male end does not exactly grip the cable(s) in place, whereas the female end does.

Matteo2000 said:

Okay, thanks. How would I check that?

Click to expand...

When you do your EFLI test. With your EFLI tester.

Okay, thanks all. Presumably I can use a long length of cable in place of the dedicated one on eBay. I have no idea where to connect it on the consumer unit though!

On the cable to use between the junction boxes and the gu10 fittings, I just read elsewhere that if I use flex it has to be the same diameter as the existing twin and earth in the ceiling (at least 1 mm). Is this correct?

Thanks.