Wired alarm sensors in UniFi Protect

What the Alarm Hub does

Many buildings already have wired door contacts, motion detectors and glass-break sensors. The Alarm Hub connects up to 32 of them, plus an emergency input. It’s powered over PoE, with support for a 12V backup battery. It also has two relay outputs, which an input can trigger directly, so they keep working even when the console is offline.

We were pleasantly surprised to see that the hub’s inputs support end-of-line resistors. With a resistor at each sensor, the hub can tell a closed door from a cut or shorted wire, so shorting a sensor’s wires cannot make an open door look closed.

How it did on a real install

We installed and tested an Alarm Hub at a customer site, and it works well. Protect shows a door opening right away, though the status sometimes takes a moment to update when the door closes again.

A SuperLink Gateway mounts inside the enclosure, which is very convenient. On this job, the hub replaced a Mercury input board from the building’s older access control system. The stairwell doors kept their existing contact sensors, now wired to the hub. In the network closets, SuperLink sensors monitor the doors, temperature and humidity.

What we’d change

Screw terminals would be better. The push-in terminals are fragile and can break, and it can be difficult to get the wires fully seated. We put a ferrule on every wire that goes into one, and we’d recommend anyone wiring an Alarm Hub does the same.

A smaller version would help too. The hub makes sense when there are many sensors to connect, but it’s too large for many of the buildings we work in. The only smaller option is the UniFi Relay, which has two inputs and needs its own power supply. On the other hand, the Alarm Hub is affordable, so it isn’t out of the question on a smaller job.