Here is my chime box opened up. Consumer units enclosures devices surge protection rotary isolators and accessories.

Hi Elliot I Connected My Nest Using Bell By Artur Bardo
British general bell transformer wiring diagram. I got mines from screwfix link to it is above. Provides constant power to a mains powered door bell. A huge range of accessories in a wide variety of finishes and profiles bg wiring devices cater for any application. With multiple voltage outputs and overload protection these power supplies are perfect for continual use and fit neatly in to a standard consumer unit. Bell transformer module 230 v ac 8 12 24 v 50 60 hz 8 va 8v 1a 12v 0667a 24v 0333a indoor 115 w white gloss continuous operation suitable on 35mm din rail accepts up to 16mm² cable introduction this bell transformer is part of the bg range of control devices and is suitable for use within any bg metal or insulated consumer unit. 230v to 8 24vac 8va door bell power power supply an 8 to 24 volt ac power supply designed to be din rail mounted.
Quick demo of how i wired the nest hello doorbell to a common uk door chime deta c3500 c3501 with a british general 8 24v 8 va bell transformer module. Can be used in a high integrity circuit. Surface mounted fuse box. Chime box removed cover of inbuilt. British general 8 24v 8va bell transformer module. For use with metal or insulated consumer units and enclosures.
British general 8 24v 8va bell transformer module. The transformer you require must be able to supply at a minimum of 12v to be able to power the camera. The bell transformer should be connected in series with an mcb not exceeding 6a. Works with a hard wired door bell stepping down the voltage from 230v to 8 24v. Free next day delivery available free collection in 5 minutes.