False alarms again! (Samsung multi)

Hi I keep getting random false alarms on my Samsung multi sensor. It is mounted on a door and should only trigger if the door is open. I keep getting an intrusion alert that says the door has been opened and then closed. The house is empty and the door locked. The sensor is brand new and the battery is 100%. The magnet is also positioned very close on top of the sensor.

Any ideas what could cause this?

Are you using Smart Home Monitoring?

Yes the monitoring is set to away and the house is empty. I have moved the magnet to within 1mm to see that fixed the problem. Previously it was set at about 6mm.

for the gen2 ST multisensor with CR2032,
I typically get about 5-30 active/inactive (acceleration) events in a week. I am certain it’s sitting on a table with no one home. Between that and vanishing battery reporting, I’ve decided this device cannot be trusted.

But I don’t get false contact alarms (the magnet is right next to it).

I’d guess your magnet gap is wide enough to make the detection marginal. I’d expect steel door to reduce the best gap range.

What’s the best alternative for the sensor?

I have monoprice contact, smartthings gen1 o/c-only, and smatthings multipurpose. They all report contacts ok. The only exception being cloud outage and low battery - when smartthings sensor battery ran low its temperature still reported but contact closures were silent.

I would use any of them for contact closure, and minimize the gap.

Since moving the magnet closer I have have no new false alarms. Looks like the magnet is quite weak. I compared the magnet with my old house alarm magnet and this is much stronger. So lesson learned with the Samsung, very small gaps needed to work correctly.
I can now safely hook this all up to a siren without fear of waking up in the night to a false alarm !

most alarms are false alarms. That should be the first guess. like 95%.

So don’t go nuts.