Power Guide

The ADC-VDB770 can be powered by a doorbell chime transformer or a plug-in DC power supply. If there is no transformer installed at the location, or if an existing transformer needs to be replaced, this page goes over the recommended specifications for a new transformer or plug-in DC power supply.

Transformers are most commonly installed next to the breaker box in a home but are also often installed in the walls of a house meaning that the wires would need to be traced to find them.

AC Doorbell Transformer

AC transformers are the primary power method of the VDB770.

Recommended Rating

    • Minimum output: 16 VAC 10 VA.
      • Add 10 VA for each additional doorbell camera to be wired to the transformer (e.g., for two doorbell cameras, the recommended output is 16 VAC 20 VA).
    • Purpose: Provides power for a permanent installation with a chime and doorbell camera.
    • Other considerations: If the transformer has multiple outputs, verify that the doorbell camera and chime are wired to the correct leads for their power needs.

    • If you received a transformer as part of your doorbell bundle, please refer to the instructions included in the transformer box.

Transformer Image

Plug-in DC Power Supply

Most Alarm.com doorbell installations make use of the existing chime and transformer in the building. A plug-in DC power supply is an alternative option.

Caution: If an ADC-VDB770 is wired to a DC power supply, a 10 Watt 10 Ohm resistor must be added to the circuit to prevent damage to the doorbell camera. The power module is still required. Existing chimes are not compatible with the DC Power Supply setup. For details on the wiring set up go to Alarm.com/doorbell/chime.

Recommended Rating

  • Minimum output: 15V, 8W.
  • Purpose: Provides power for a permanent installation.
  • Please see ADC-VDBA-PSU-DC as an approved DC Power Supply for the ADC-VDB770

DC Power Supply Image

Copyright © 2000-2021, Alarm.com. All rights reserved.
Alarm.com and the Alarm.com Logo are registered trademarks of Alarm.com.