GDS3710 Relay Polarity


Hi, is there any reason the documentation diagrams recommend to connect the Ground (V-) to the COM2 (Electric Strike) instead of the Line (V+)? Is it just to simplify the wiring diagram when using IN1 (Door Lock Switch)? Thanks!


@luketc: Are you referring to Page 2 of this document?

The V+/V- is 3rd party power supply usually referring to the independent power source of electronic strike or locker. The V- to COM2 is not applying constant high voltage to the port to protect and extend the life of electronic component, although it will also work if you connect V+ to COM2 (just opposite connection or the whole wiring), this should be electric common sense and normal wiring habit. The IN1 (Door Lock Switch) should have its own circuit or voltage and should NOT suck power from GDS3710 (GDS3710 will NOT provide power to the switch circuit).

Hope I explained clearly, feel free to comment if not clear.

Thank you for your interest to GDS3710.


Thanks John. Makes sense, I will follow the suggested polarity then. In my case, I plan to use POS for the GDS3710, and one additional power-supply (12v) for the Switch (IN1) and Strike (COM2).

Additionally, I plan to use the Doorbell (COM1) to notify my home-automation system, so COM1 will use the home-automation’s zone-circuit (2.5V). Is it recommended to put an additional relay in the middle to protect/isolate the home-automation circuit from the GDS3710?


@luketc: Yes, additional 12V DC power source for the strike and switch is good.

For COM1, if the Home Automation zone-circuit is 2.5V, you can just connect directly, maybe just add a protection diode, similar to the strike:

Or refer to Page 42 of User Manual:

I don’t know the Home Automation device you used, but I guess it should work. You can test and advise the result. If not working, then we can start diagnosing and see what might be issue.

Thank you for using GDS3710.


Cool, I will follow up once I test with the home automation system (Leviton’s OmniPro II)

BTW I already did a quick test connecting the GDS3710’s SIP directly to the OmniTouch 7 and looks like it work, even with no SIP server.


@luketc: Yes, it is designed to work with or without SIP Server. For some application like remote warehouse or storage etc., w/o internet, just static IP (direct IP call) should make the solution function.

There are lots of resource and document here:

Thank you for using GDS3710!