Can I use three pin plug 240V mains to supply DIN rail transformer?

[stefan9107]

I recently moved into a new house that had a ring camera hard wired using bell wire. This was also hooked up to the houses old chime. I didn't want the ring camera so switched it for Eufy C31 which I also want to hardwire in the same way. Unfortunately the transformer for the Ring only supplied 8VA and I need a whopping 30VA apparently... It did survive a while as the battery was fully charged, but over time it just lost power bit by bit.

The existing install has the transformer wired up to a 3-pin plug that goes into a socket under the stairs. So that I don't have to re-wire everything I want to use the same bell wire and a 3-pin plug, but just swap the transformer. The camera needs AC rather than DC so an LED driver is out, but I did find this Vemer DIN rail transformer that fits the bill.

https://www.amazon.co.uk/dp/B00F4QGVIA/?th=1

The 3-pin obviously has an earth, which the transformer doesn't have the facility for... so what do I do with it?
I'm not planning put the transformer into the consumer unit as there isn't space, so I just want it standalone in its own enclosure.

Do I just use 2-core for the plug and forget the earth?
Do I leave the earth hanging and just tape up the end?
Do I extend the earth and run it to the consumer unit (also under the stairs not far away).

Any help is much appreciated?

 

[mainline]

I recently moved into a new house that had a ring camera hard wired using bell wire. This was also hooked up to the houses old chime. I didn't want the ring camera so switched it for Eufy C31 which I also want to hardwire in the same way. Unfortunately the transformer for the Ring only supplied 8VA and I need a whopping 30VA apparently... It did survive a while as the battery was fully charged, but over time it just lost power bit by bit.

The existing install has the transformer wired up to a 3-pin plug that goes into a socket under the stairs. So that I don't have to re-wire everything I want to use the same bell wire and a 3-pin plug, but just swap the transformer. The camera needs AC rather than DC so an LED driver is out, but I did find this Vemer DIN rail transformer that fits the bill.

https://www.amazon.co.uk/dp/B00F4QGVIA/?th=1

The 3-pin obviously has an earth, which the transformer doesn't have the facility for... so what do I do with it?
I'm not planning put the transformer into the consumer unit as there isn't space, so I just want it standalone in its own enclosure.

Do I just use 2-core for the plug and forget the earth?
Do I leave the earth hanging and just tape up the end?
Do I extend the earth and run it to the consumer unit (also under the stairs not far away).

Any help is much appreciated?

The transformer should be in a suitable din rail enclosure where the earth would be terminated.

Can you not buy a 24v ac plug in transformer ?

 

[stefan9107]

The transformer should be in a suitable din rail enclosure where the earth would be terminated.

Can you not buy a 24v ac plug in transformer ?

You can, but not with the required VA. They all seem to be only 8-12VA whereas I need 30.
They also seem to be mostly AC to DC whereas I need to stay AC.

 

[mainline]

You can, but not with the required VA. They all seem to be only 8-12VA whereas I need 30.

40va or more should be easy to find.

I just had a quick look.

eBay item 326344090572

eBay item 312590907191

eBay item 153422866636

 

[w0z]

I recently moved into a new house that had a ring camera hard wired using bell wire. This was also hooked up to the houses old chime. I didn't want the ring camera so switched it for Eufy C31 which I also want to hardwire in the same way. Unfortunately the transformer for the Ring only supplied 8VA and I need a whopping 30VA apparently... It did survive a while as the battery was fully charged, but over time it just lost power bit by bit.

The existing install has the transformer wired up to a 3-pin plug that goes into a socket under the stairs. So that I don't have to re-wire everything I want to use the same bell wire and a 3-pin plug, but just swap the transformer. The camera needs AC rather than DC so an LED driver is out, but I did find this Vemer DIN rail transformer that fits the bill.

https://www.amazon.co.uk/dp/B00F4QGVIA/?th=1

The 3-pin obviously has an earth, which the transformer doesn't have the facility for... so what do I do with it?
I'm not planning put the transformer into the consumer unit as there isn't space, so I just want it standalone in its own enclosure.

Do I just use 2-core for the plug and forget the earth?
Do I leave the earth hanging and just tape up the end?
Do I extend the earth and run it to the consumer unit (also under the stairs not far away).

Any help is much appreciated?

As long as you fix the transformer into an enclosure which fingers can't access and the mains cable can't be pulled out (a cable wrap around the cable on the inside of the hole (or gland) the mains cable passes through is usually adequate) it will be fine.
What you can't do is leave it free standing where mains terminals are accessible.
As long as the DIN rail transformers are isolated (always the case) no earth is required so you can come in with 2 core (or 3 core and either ignore the earth in the box or if there's a suitable hole on the mounting plate of the transformer connect it there -it matters not. And out with 2 core bell wire.
Also a low amp fuse in the plug as an extra precaution 2A if you can find one or 3A more common.

 

[brianmoooore]

Open for correction, but doesn''t the transformer have to meet certain standards for this application? For a conventional 50Hz transformer, either the primary and secondary windings must be side by side with insulation between them, or, if they are wound on top of each other, must have a earthed metal shield between them, usually thick copper foil, insulated so as not to become a shorted turn.

 

[w0z]

Open for correction, but doesn''t the transformer have to meet certain standards for this application? For a conventional 50Hz transformer, either the primary and secondary windings must be side by side with insulation between them, or, if they are wound on top of each other, must have a earthed metal shield between them, usually thick copper foil, insulated so as not to become a shorted turn.

You may be correct although I've not seen that regulation.
I assumed (dangerous I know) that this type of DIN rail transformer would be compliant as specifically quoted as being suitable for LV doorbells etc. If they do have an earthed metal shield or conventional transformer which I doubt (unfortunately I've never had the opportunity to dissect one) then connecting the earth to the mount would cover that, but I'm fairly sure most of them are switch mode with (hopefully) well designed separation between LV and HV.
Yes the worst case scenario is mains on the LV side, but the presence of mains on the LV side could still happen whether or not there's an earth. An RCD should protect if plugged in rather that installed in the (metal) enclosure