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Create a "BRK/First Alert" smoke detector connector adapter
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Which circuit breaker powers the smoke alarms? None shall ever know, for every breaker was marked "OLD BATHROOM GCFI.docx.v2.REAL.bak.bak~" when the house was purchased.

It would be easier to figure out if I could plug something in, like this tool for figuring out which breaker powers something which I already own (although I've had mixed luck with it). But the connector that's currently wired in is a big molex-ish connector that I can't get alligator clips on.

I purchased this smoke detector connector adapter, intending to cut it up, wire that to a plug and then go Live WiresAdapterPlugCircuit Detector. It arrived and isn't remotely close to fitting, it's like twice as large as the wired connector.

The connector on the live wires seems to be a "First Alert / BRK"-style female connector. They sell a lot of adapters on Amazon that take you from other connectors to "BRK", but I can't find any that take you from "BRK" to anything else.

The practical solution here is probably to stand on a rubber mat and just carefully get the live wire into a Wago connector, but after some consideration I realize that they sell a "DIY" BRK Connector Male Adapter for the steep-but-not-unreasonable price of $14.

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epriestley created this task.

Here's my nice safe smoke detector power adapter:

Screen Shot 2022-12-14 at 3.22.49 PM.png (595×797 px, 838 KB)

This connector has a 4mm pin pitch, but I had a great deal of difficulty finding a likely-seeming bare connector with a 4mm pitch. After resigning myself to a Digikey quest for a connector that will fit a board on T13692, which also has a "4mm" pitch I realize the pitch is probably not 4mm but 3.96mm -- a wonderful pitch for which many connectors are readily available.

This is likely a JST-VH 4 Pin connector.

The genuine article is not a JST-VH 4-pin connector -- the connecting clip is a little different, and there's no hole in the housing for (unused) pin #2. However, the pin size and spacing is right, so you can cut the connecting clip off a JST-VH and melt one of the pins out and the connector will fit well enough.

I traced the alarms back to Breaker #8 in Panel #2 (the detector tool actually worked okay this time). I disconnected the breaker and verified that killed the circuit. I swapped the alarms and updated the map of known breakers with this new information:

Screen Shot 2022-12-20 at 8.39.38 PM.png (222×354 px, 22 KB)

epriestley renamed this task from Create a "BRK/First Alert" smoke detector connector adapter to Create a "BRK/First Alert" smoke detector connector adapter.Nov 16 2023, 8:43 PM