What is the Power Source for a Honeywell VISTA 20P?

The power source for a Honeywell VISTA 20P is the Honeywell 1321 AC Transformer. This is a 16.5VAC, 25VA transformer that will provide reliable power to the system. A backup battery of at least 12V, 4Ah can also be added to keep the system running in the event of an electrical outage.

All alarm systems require electricity for power. This is almost always provided in the form of a plug-in transformer and a backup battery. But not all alarm systems require the same amount or type of power. Using the correct transformer is very important for preventing damage to the system.

In the case of the Honeywell VISTA 20P, the recommended transformer to use is the Honeywell 1321. If you ever lose or damage your transformer, you can purchase a new one from Alarm Grid. But please make absolutely sure that you purchase the correct type, as we do not accept returns for alarm system transformers.

The Honeywell 1321 provides 16.5VAC, 25VA of power, which is perfect for powering a VISTA 20P. Since AC power is being used, you do not have to worry about polarity, and either colored wire can go to either terminal. We recommend using 18-gauge, 2 conductor wire or a Honeywell LT-Cable to complete the connection. The Honeywell LT-Cable is great for DIY users, since it will eliminate the need for stripping wires.

We also strongly advise users to add a backup battery to keep the system running in the event of AC power loss. The battery should be rated at 12V and at least 4Ah. A great backup battery to use for this purpose is the UltraTech 1240. Remember, the system will display trouble conditions for both AC power loss and backup battery loss. If the system loses both AC power and battery power, then it will shut down entirely.

Note: There are also shared transformer options when using a Vista 20P with an alarm system communicator that has its own plug-in power supply. More information can be found here.