Wired Doorbells

Wired doorbells at trade prices from Harbro Electrical, Peterlee. The range covers three products: the Byron 720K complete traditional wired doorbell kit including transformer at £17.25 + VAT, the Dahua VDKP01-BG 2K wired video doorbell kit with wireless Wi-Fi chime at £66.00 + VAT, and the Ener-J Smart Flexi which can be connected to an existing 2-wire bell circuit for continuous mains power at £49.00 + VAT.

All prices exclude 20% VAT. Doorbell transformers are stocked separately - see the dedicated Doorbell Transformer collection. Same-day collection from our Peterlee trade counter at SR8 2LY. Free UK Mainland delivery on orders over £70.

Byron 720K £17.25 + VAT • complete kit with transformer included Dahua VDKP01-BG £66.00 + VAT • 2K video + Wi-Fi chime Ener-J Smart Flexi £49.00 + VAT • connects to existing bell wire Doorbell transformers • stocked separately

How a wired doorbell circuit works

A wired doorbell uses a simple low-voltage bell circuit. A doorbell transformer steps mains voltage (230V AC) down to 8 to 12V AC. Two-core bell wire carries this low voltage from the transformer to the outdoor push button and from the transformer to the indoor chime unit. When the push is pressed, it completes the circuit and activates the chime.

Component	Role	Notes
Doorbell transformer	Steps 230V mains down to 8-12V AC	Required for all wired circuits. Byron 720K kit includes one. All others need a separate transformer.
Bell wire (2-core)	Carries low voltage from transformer to push and chime	Thin 2-core conductor. Run behind walls or surface-clipped.
Push button	Completes the circuit when pressed	Outdoor rated. Mounts at the door frame or pillar.
Chime unit	Produces the audible alert	Electro-mechanical (Byron) or wireless Wi-Fi (Dahua, Ener-J USB).

The transformer must be installed by a qualified electrician as it connects to the mains. The low-voltage bell wire can typically be run by a competent DIYer once the transformer is in place.

Byron 720K Wired Doorbell Kit

The Byron 720K at £17.25 + VAT is a complete traditional wired doorbell kit - everything needed for a new hardwired installation in one box. No separate transformer purchase required.

Electro-mechanical doorbell chime: classic ding-dong sound, 85dB
White bell push with clean, simple styling
8V 1A transformer included - no separate transformer needed
Bell wire, cable clips and fixing pack included
Simple 2-wire installation
Wall-mounted chime unit, White finish

The Byron 720K is the correct choice for new-build and refurb installs where a reliable traditional wired doorbell is required without video or app connectivity. The included transformer is matched to the chime unit, eliminating any voltage compatibility risk.

Dahua VDKP01-BG - 2K Wired Video Doorbell Kit

The Dahua VDKP01-BGat £66.00 + VAT is a wired video doorbell kit in Black. The doorbell unit is hardwired for continuous power, the chime unit is wireless (Wi-Fi) and connects to the home network. Managed via the Dahua DMSS mobile app.

Specification	Dahua VDKP01-BG
Price + VAT	£66.00 + VAT (£79.20 inc.)
Finish	Black
Video	2K high-resolution with ultra-wide fisheye lens
Motion detection	Passive IR (PIR)
Audio	Two-way - speak to visitors via DMSS app
Connectivity	2.4GHz Wi-Fi 6
Power (doorbell)	Wired - requires external power supply
Chime unit	Wireless Wi-Fi - indoor, customisable ringtones and volume via app
App	Dahua DMSS (iOS and Android)
SKU	VDKP01-BG

The fisheye lens provides a wider field of view than a standard doorbell camera, capturing more of the approach and the ground in front of the door - useful for seeing packages left on the doorstep. The wireless Wi-Fi chime can be placed anywhere in the home within Wi-Fi range and can be paired with multiple doorbells simultaneously. A suitable wired power supply connection is required at the doorbell position - confirm the installation power requirements before ordering.

Ener-J Smart Flexi - wired video doorbell option

The Ener-J Smart Flexi (SHA5357) at £49.00 + VAT is a dual-power video doorbell: it runs on its 5200mAh rechargeable battery wirelessly, or it connects to an existing 2-wire bell circuit for a continuous wired mains supply. For properties with bell wire already in place, the wired connection eliminates the need to ever recharge the battery.

Connects to existing 2-core bell wire - no new cable run needed on a retrofit
Continuous mains power when wired - no battery management required
1080p HD video with HDR and night vision
110-degree wide field of view
Two-way audio with siren
USB chime included - plugs into any USB socket indoors
No hub, no monthly subscription

The Ener-J Smart Flexi is the most cost-effective wired video doorbell in the Harbro range at £49.00 + VAT. For retrofit installs where bell wire runs to the push position, this is the most straightforward upgrade: connect the existing bell wires to the Ener-J terminals, replace the old push and chime, and the system is operational on mains power without any new cable work.

Doorbell Transformers at Harbro

The Byron 720K includes an 8V 1A transformer in its kit. For the Dahua VDKP01-BG and Ener-J Smart Flexi in wired mode, a separate transformer is required unless one is already in place. Harbro stocks doorbell transformers suitable for standard residential bell circuits.

Shop Doorbell Transformers →

Need a wireless doorbell instead?

For retrofit, rental and no-cable installs, the wireless doorbell range includes Ajax AI video doorbells, Ener-J battery video doorbells and Knightsbridge wireless chime kits.

Browse Wireless Doorbells →

Peterlee trade counter: same-day wired doorbell stock

Byron and Dahua wired doorbells and doorbell transformers at 5 & 6 Whitworth Road, Peterlee, SR8 2LY. Call 0191 518 1998 to check stock. Mon-Thu 7:30am-5:00pm, Fri 7:30am-4:00pm, Sat 8:30am-12:30pm.

Related collections

Wired Doorbells: frequently asked questions

What is a wired doorbell?

A wired doorbell uses a low-voltage bell circuit to connect the outdoor push button to the indoor chime via 2-core bell wire. The circuit is powered by a doorbell transformer stepping mains voltage down to 8 to 12V AC. Wired doorbells are more reliable than battery-powered wireless models - no batteries to replace, no radio interference. They are the standard specification for new builds and full refurbishments. Harbro stocks the Byron 720K traditional wired kit, the Dahua VDKP01-BG 2K wired video doorbell and the Ener-J Smart Flexi in wired mode.

Do I need a transformer for a wired doorbell?

Yes, unless the kit already includes one. The Byron 720K kit includes an 8V 1A transformer. For the Dahua VDKP01-BG and the Ener-J Smart Flexi in wired mode, a separate transformer is required from the Doorbell Transformer collection. For retrofit installs with an existing transformer already in place, confirm the output voltage matches the new doorbell specification before installing.

What voltage transformer does a wired doorbell need?

Most residential wired doorbells require an 8V AC transformer. Some larger electro-mechanical chimes may require 12V AC. Check the chime unit specification before selecting a transformer. The Byron 720K includes an 8V 1A transformer matched to its chime. For other installations, separate transformers are available in the Doorbell Transformer collection.

What is a wired video doorbell?

A wired video doorbell uses a mains or low-voltage AC supply rather than a battery as its primary power source. This eliminates the need to periodically recharge a battery. The Dahua VDKP01-BG is a 2K wired video doorbell that records footage, detects motion via PIR and sends live video and two-way audio to the DMSS app. The Ener-J Smart Flexi can also be wired to an existing bell circuit for continuous mains power alongside its 1080p video capability.

Can a wired video doorbell replace an existing wired doorbell?

Yes, in most cases. If existing bell wire runs from the push position to a chime location, a wired video doorbell can typically use the same cable. The Ener-J Smart Flexi is designed specifically for this retrofit scenario - it connects directly to standard 2-wire bell wiring at the push position. Check the voltage and current requirements of the new video doorbell against the existing transformer specification before installing.

What is the difference between the Byron 720K and the Dahua VDKP01-BG?

The Byron 720K at £17.25 + VAT is a traditional wired doorbell: mechanical chime, bell push, 8V transformer, wire and fixings all included. Classic ding-dong sound, no video, no app. The Dahua VDKP01-BG at £66.00 + VAT is a 2K wired video doorbell with fisheye lens, PIR motion detection, two-way audio, Wi-Fi 6 and a wireless chime unit managed via the DMSS app.

How do I install a wired doorbell?

A standard wired doorbell installation follows four steps: (1) install and connect the transformer to a mains junction box - this step requires a qualified electrician; (2) run 2-core bell wire from the transformer to the outdoor push button position; (3) run bell wire from the transformer to the indoor chime position; (4) connect and test. For wired video doorbells, the push unit connects to the power supply wires at the door. Refer to the specific product installation guide for the exact wiring diagram.

Where can I buy wired doorbells in the North East?

Wired doorbells from Byron and Dahua, and doorbell transformers, are stocked at Harbro Electrical, 5 & 6 Whitworth Road, Peterlee, Co Durham, SR8 2LY. Mon to Thu 7:30am to 5:00pm, Fri 7:30am to 4:00pm, Sat 8:30am to 12:30pm. Call 0191 518 1998 to check stock before visiting. Free UK Mainland delivery on orders over £70.