The motion sensor was salvaged and has four wires:

  1. Black
  2. White
  3. Red
  4. Green

Only the sensor was salvaged. The rest was discarded.

Is the convention black or red = hot, white = neutral, green control wire applicable here? It would be nice to understand the voltage associated with the control wire (AC / DC and voltage range). It would be sad if applying 120V AC were to damage / fry this sensor.

Any references or analytical techniques are appreciated. Thanks

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This thing is made for the North American market (note the Heath/Zenith branding, classic zombification of old loved brands which would only be meaningful to US/Canada customers), and those stalk motion sensors are commodity items on a modular fixture. You can buy similar motion sensors off-the-shelf. Any component maker who wants a UL listing, or who sells to fixture builders who want a UL listing, will use US standard colors.

And red/black/white/green are the exactly the textbook standard color set. Given the branding and commodity nature of these parts, the chance of them being anything else is vanishingly small.

UL and NEC say Green is safety-ground... and White is neutral.

Black and red are "hots" but NEC does not specify further. By convention, black is always-hot, and red is switched-hot. But a component maker could go another way and face only the wrath of their customers. It probably won't fry the sensor if you reversed them.

Now, how did this stripped unit come into your possession? Consider the possibility it's maybe because the sensor is roached.

  • \$\begingroup\$ I took down a non working unit and saved the sensor with the hope that it is still good. I want to develop a test plan, but to do this I need to understand the wiring diagram \$\endgroup\$ – gatorback Jan 6 '17 at 23:15

In AC wiring, green is always Safety Ground. White is Neutral and Black is hot, so I'd guess Red is the switched output, and will be 120 VAC when motion is sensed to turn on the light.

Edit: I have a Heath/Zenith motion sensor light fixture (model 5412). The installation instructions show black and white wires for hot and neutral input, and mention a green screw for a ground wire. As the motion sensor and lamp sockets come as one assembly, there is no mention of the connection from the output of the sensor to the lamp sockets.

  • \$\begingroup\$ Any ideas how to safely (i.e. not damage sensor) verify this would be appreciated. Thank you \$\endgroup\$ – gatorback Jan 6 '17 at 17:27
  • \$\begingroup\$ A green wire is certainly not always safety ground. That assumption can get you killed. \$\endgroup\$ – vofa Jan 6 '17 at 19:35
  • \$\begingroup\$ Every civilized nation has harmonised to green=ground for new work. More the issue is that safety ground can have lethal voltage on it. \$\endgroup\$ – Harper - Reinstate Monica Jan 6 '17 at 23:28

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