How many sirens can be wired to the VISTA 21iP?

Okay, so you want to wire multiple sirens to your Honeywell Vista 21iP, but probably noticed there's only 1 set of terminals for the siren.

Well, fear not, you can wire multiple sirens to your Vista 21iP using parallel wiring. That involves wiring all of the positive terminals of the sirens to the positive on the 21iP (terminal 3) and all of the negatives of the sirens to the negative on the 21iP (terminal 4).

The main concern is going to be figuring out how much current the sirens will all draw. You need to add those up based on the sirens you're using. You will get a total of 2 amps from 12VDC siren terminals if you're using the built-in power supply. You need to see what the power output is for each of the sirens you will be connection.

For example, if you're wiring multiple Honeywell WAVE2 sirens, each one draws up to 0.5 amps at 12 VDC. That means you can wire up to four.

So consider you're wiring multiple Honeywell 702 wired sirens.  Each one of those will draw up to 1.2 amps. Uh oh. Now you can only wire one! 

The solution?  You can hook up an auxiliary power supply like the Honeywell AD12612 or the Altronix SMP3 so that you can add more sirens without overdrawing power from the panel.

Or, of course, you can always opt for a wireless receiver like the Honeywell 5881ENL, which will give you up to 8 wireless zones. In addition, to the wireless zones, you can also add an unlimited amount of wireless 5800WAVE sirens, which will get power from a wall outlet and therefore will not affect your Vista 21iPs siren output.