Gentex GX-90 Question

Hello, all you Gentex fans. I have a question about the GX-90 mini horn-strobe. I saw that it had 2 sets of connections and I tried one with 18 volts (undervolted so I wouldn’t blow out my eardrum) and both the horn and strobe operated fine. I tried the other set and did the same thing. So is it two-wire? Why does it have 2 sets of wire leads then? Help would be greatly appreciated. Thank you!

Yes, it is two-wire. The wire leads are for supervisory purposes. Power into the alarm, and power out of the alarm. That way if it somehow gets removed from the wall by accident it breaks the connection and shows a trouble on the panel.


Okay, thanks. If I were to code it (to a panel I might get this summer :smiley: ) would the strobe get damaged because of the pulsing current? Or would the strobe just flash weird?

Wait a second, I think I made a mistake.



Does it look like this?





If so there’s two jumpers above the terminal block that must be removed to make it 4-wire.

Here’s a picture of the back of mine. I don’t believe there are any jumpers, but I could be incorrect.



No, mine has wire leads.

Yours has a connector, which in that picture appears to be disconnected.



Disconnecting that connector would change it to 4 wire.

If it matters (which I don’t think it does), it’s rebranded by Simplex.

Andrew, your picture is of the newer one with the transparent strobe, and my picture was of the older one with the translucent strobe.



And Alex, you can split it into 4-wire operation with the newer one, but not the older one.



Here’s the wiring diagram for the older one:



Actually, you can make the older one 4-wire. (I was stupid for doing this. IT IS IRREVERSIBLE!!!)



I CUT the wires going to the connector and it became 4-wire. Any side off the connector is fine.

Or you can unplug the connector, it’s designed for that…

Here’s the back of mine, I apologize for the late reply. The blue tape is from my attempts at separating the wires.