How to Install an Alarm.com VDB770

Wire the ADC-VDB770 without a chime

The ADC-VDB770 can be powered without a chime using either of the following:

  • DC adapter with a power rating of 15-30V DC, 8W minimum
  • AC transformer with a power rating of 16-30V AC, 10-30VA.

Important: This chimeless configuration requires a resistor rated at 10 Watts 10 Ohms with 5% tolerance.

To wire the ADC-VDB770 without a chime using a DC adapter

  1. On the power module, attach the white wires interchangeably to a resistor (10 Watts 10 Ohms with 5% tolerance).
  2. Attach the gray wires interchangeably to a DC transformer and the ADC-VDB770.
  3. On the ADC-VDB770, attach the remaining wire to the transformer.

To wire the ADC-VDB770 without a chime using an AC transformer:

  1. On the power module, attach the white wires interchangeably to a resistor (10 Watts 10 Ohms with 5% tolerance).
  2. Attach the gray wires interchangeably to an AC transformer and the ADC-VDB770.
  3. On the ADC-VDB770, attach the remaining wire to the transformer.

The Video Doorbell Wall Power Supply Kit (ADC-VDBA-PSU-PD) has separate wiring instructions, see below.

The Video Doorbell Wall Power Supply Kit (ADC-VDBA-PSU-DC) is a DC plug-in power supply rated at 16V, 1.25A (20W). The Video Doorbell Wall Power Supply Kit is designed to easily power the ADC-VDB770 when not using an existing chime circuit. This supply can be used for installations where there is no existing wiring or where the existing setup is incompatible.

Important: The Wall Power Supply Kit should only be installed when no wired chime is used in the circuit.

Installation and wiring

Required materials

  • A 10 W / 10 Ohm resistor (or flameproof 5W / 3.9 Ohm resistor without a power module)
  • Wires for the power supply

Power module installed

No power module


Caution : Power will run through the resistor at all times using this configuration. You must use a flameproof resistor and ensure it is thermally isolated in the installation.