I have a Doorbird D202 Doorbell and a Hormann Promatic Garage door. I want to use the Doorbird to Open the Garage Door

This is the connection I believe we need to connect the Doorbird to in the Hormann (Image 12): Hormann Connector

This is what it says in regard to the Hormann Manual and Figure 12 above:

Connecting External IMPULSE button

Would this connect to the Doorbirds "Conventional door opener button" wiring?

Conventional door opener button Diagram

Here is the wiring instructions for the Doorbird:

enter image description here

Here is the spec sheet for the Doorbird: https://cdn.shopify.com/s/files/1/0066/8149/3559/files/manual_d20x_en_de.pdf and https://www.doorbird.com/downloads/datasheet_d202bb_en.pdf

Here is the spec sheet for the Hormann Garage Door https://www.thegaragedoorcentre.co.uk/userfiles/downloads/Hormann%20Promatic%20P%20Fitting%20Instructions.pdf

  • 1
    Hormann support came back on this question with "It would have to go to the purple, purple electric door opener on the Doorbird. The gate would need a normally open relay to work." I will try this Aug 29, 2019 at 15:35
  • 1
    Good to know - that falls in line with my description below.
    – JPhi1618
    Aug 29, 2019 at 15:37

1 Answer 1


Without reading all the linked manuals, I will try to answer your question. Control circuits come in a few forms, but two major types are "input voltage" and "contact closure".

For instance, for a typical air conditioner to turn on, you need to apply 24 volts across the terminals for its relay to make it turn on. This voltage is supplied by an external transformer. You can't just hook up a basic switch to the unit and make it turn on and off. You have to supply an external voltage. This is probably also the case in commercial entry doors that use a solenoid device to open a latch.

The contact closure control is another major type and is usually what garage door openers use. If you take the two wires going to your garage door button and touch them together (just like the switch does), then the door opens. You're not supplying a voltage - just connecting a wire momentarily.

When your doorbell system refers to "zero potential" its talking about a simple contact closure that doesn't supply voltage. Connecting the "Electric Door Opener" wires to terminals 20 and 21a of your garage door opener should do what you want. To test this, you could power up the doorbell and use the door opener function while measuring continuity between the two electric door opener wires. They should be normally open and should have continuity briefly when the door open command is sent.

Terminal 5 on the garage door opener is used to supply a voltage to something like a lighted button or some other "smart" controller that needs power to operate.

  • thanks for the post...i will try this asap. Aug 29, 2019 at 15:43
  • Works perfectly. Quite a mission to install the Doorbird in a concrete wall but it's in! Here's a video of it controlling the Garage Door youtube.com/watch?v=UjGWx6WQTFQ Sep 6, 2019 at 20:08

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