Diagnosis
The Nexx NXG-200 Smart WiFi Garage Controller is engineered as a single-channel relay device. This means it contains one internal electromagnetic switch designed to mimic a single momentary press of a wall-mounted push button. Because the hardware only possesses one set of dry-contact output terminals, it can only send an electrical pulse to one motor control board at a time. If you have a multi-car garage with independent motors for each door, attempting to wire multiple motors to a single NXG-200 will either result in no doors opening (due to current draw limitations) or, if wired in parallel, both doors opening and closing simultaneously. There is no software setting or wiring configuration within the NXG-200 that allows for "zoning" or independent control of multiple motors from a single unit, as the physical relay cannot be split into multiple independent circuits.
How to Fix It
To achieve independent control over multiple garage doors, you must install one dedicated NXG-200 unit for every individual motor. Follow these steps for a multi-door installation:
- Purchase one NXG-200 unit per garage door motor.
- Mount each controller within 3-5 feet of its respective motor to ensure the 22AWG wiring does not suffer from significant voltage drop.
- Connect the two output wires from the first NXG-200 to the push-button terminals on Motor A.
- Connect the two output wires from the second NXG-200 to the push-button terminals on Motor B.
- Power each unit using the provided 5V DC power adapter, ensuring each has access to a nearby AC outlet.
- Open the Nexx app and add the first device. Name it specifically (e.g., "Left Garage Door") to avoid confusion.
- Repeat the pairing process for the second unit, naming it accordingly (e.g., "Right Garage Door").
- Test each door independently via the app to confirm the relays are triggering the correct motors.
If That Didn't Work
- If you have a single motor that operates two doors via a shared drive rail, you only need one NXG-200. In this specific mechanical configuration, the motor is the single point of failure and control; triggering that one motor will move both doors. Wire the unit to that single motor's wall-button terminals.
- If you are limited on power outlets for multiple units, use a high-quality power strip with surge protection. However, avoid using cheap extensions for the 5V DC cables, as this can cause the WiFi module to reboot during the relay click due to power instability.
- If you find the app interface cluttered with multiple devices, check if your smart home ecosystem (like Google Home or Amazon Alexa) allows you to group the devices into a "Garage" room. This allows you to say "Open the Garage" to trigger all NXG-200 units simultaneously while maintaining the ability to control them individually.
- If the relay is clicking but the door isn't moving, verify that your motor is a "dry contact" type. Some very old motors use a proprietary signal that the NXG-200 cannot replicate. In these rare cases, you would need an external relay interface between the NXG-200 and the motor.
Heads Up
- Always ensure the magnetic reed sensor is mounted precisely on the door frame and the magnet is on the door itself with a gap of no more than 0.5 inches; otherwise, the app will report the door as "Open" when it is actually "Closed."
- Avoid using heavy-gauge electrical wire for the relay connections; the thin 22AWG wire provided is ideal. Using thick 12AWG house wire can put undue stress on the small terminal blocks and cause them to snap.
- Ensure your 2.4GHz WiFi signal is strong at the motor location. Garage walls are often reinforced with concrete or metal, which act as Faraday cages. If the NXG-200 frequently goes offline, install a WiFi extender halfway between your router and the garage.
- Periodically check the wiring connections for vibration looseness. Garage motors vibrate significantly during operation, which can loosen the screw terminals over time, leading to intermittent trigger failures.