Just wondering if the hive mind can help…

I’m trying to figure out how to connect up a Nest Hello doorbell – the existing (perfectly serviceable normal – I know, don’t ask) doorbell isn’t hard wired and the Nest needs a transformer to function.

I’ve figured out I can connect the Nest Hello to a google mini speaker thing which will then act as the “chime” but I can’t work out how to install the transformer. Most doorbell transformers are hard wired to a fuse box / consumer unit – which I have zero intention of touching.

I’m therefore wondering if it’s possible to wire up the transformer to a normal power lead and fused plug – like any other consumer electronic item? If that works I’ll wire it up, plug it into a socket and then mount it out of sight.

The transformer is this one:

https://www.screwfix.com/p/british-general-8-24v-8va-bell-transformer-module/8707p

Could that be wired to a mains lead and plug?

Thanks in advance.

That’s a transformer that’s designed to be fastened to a DIN rail, so you’d need an additional enclosure.

https://www.screwfix.com/p/wylex-ese2-ip40-2-module-unpopulated-din-enclosure/32311?_requestid=203810

Should work fine with Nest.

As above that’s a din rail mounted transformer but you could always fit it in an adaptable box with din rail and glands for cable access.

Understood on the DIN rail – thanks for the advice but it is safe to wire up to a mains lead and fused plug on one side and then connect to the Nest Hello on the other side?

Yeah it would work no issue, safe would depend on where you put the transformer. Ideally out the way and in a mounted box.

sounds complicated. just buy one of these?

Yes it will work.

No need to use a DIN rail transformer, just buy a plug in power supply and plug it into the nearest socket

I used a normal 8v AC (might be DC) transformer straight from the plug for a vuebell, using some of the spare alarm cable wires. It sounds as though you already have good access from the CU to the door, so your (and others) solution sounds neater.

jam bo – looked at the item you posted but the cable length is too short and it’s not designed for continuous operation. Also comes from China so will probably burn the house down at some point 🙂

Also comes from China so will probably burn the house down at some point

Phew, thank goodness none of us have any Chinese manufactured electrical items in our homes!

johnners – get your point but for years China has allowed its traders to fraudulently use the CE mark (normally used to indicate compliance with European safety standards) to indicate China Export. It fools consumers and professionals and there’s plenty of evidence from Trading Standards of huge volumes of chinese made electronics being unsafe / a fire risk:

https://support.ce-check.eu/hc/en-us/articles/360008642600-How-To-Distinguish-A-Real-CE-Mark-From-A-Fake-Chinese-Export-Mark

This has also been a problem with PPE in Covid with government’s buying equipment from China that then fails basic quality tests – Italy and Spain have both had issues with this.

Another issue with the fake CE marked electrical equipment aside to the risk to consumers is that some insurers won’t pay out for fire damage when the ignition source is equipment that isn’t compliant with relevant legislation and standards.

A quick / safe way of buying online is to look for UK Ltd companies or only buying stuff from Amazon when Amazon UK is the seller. A lot of the apparently UK “sellers” are chinese or hong kong traders when you start to poke around the company details and Amazon will only take the commercial risk selling items that have actually been tested.

Also see:

https://www.tradingstandards.uk/news-policy/news-room/2016/warning-over-fake-chargers-and-second-hand-electrics

https://www.electricalsafetyfirst.org.uk/guidance/product-safety/chargers/

Can you use a mini speaker as a chime. Thought you needed a home hub.

Our nest doorbell was temporarily connected to a transformer with a plug until the electrician could source a correctly rated transformer.

Just installed one of these last week. I already had a wired doorbell so just replaced the transformer, but yes you can put a plug on a normal transformer and power it that way. Or butcher a normal plug transformer.

For transformers you need to look at the continuous power rating…I got a Protec 24v transformer with 12v, 16v and 24v outputs and originally intended to connect to the 16v output as the Nest Hello paperwork says it needs 16v to operate, but reading the spec of the transformer it was only rated for continuous use at 12v. However checking with Nest for the UK it actually only needs 12v continuous to work.

Edit: for non DIN mounted transformer (the Protek is DIN mounted), look for a Friedland transformer which is flat mount (and what I had before replacing with the Protek) and you can put it in any old plastic box.

Here’s a Friedland transformer but you need to check it can output 12v continuous. Some doorbells don’t need the power supply to be continuous but the Nest Hello needs 12v continuous.

https://www.fruugo.co.uk/friedland-e3538n-bell-transformer-12-v-ac-15-a/p-5733524-12762849