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I'm going to be adding some Particle Photon relay control to some receptacles so I can remotely turn on and off appliances and lighting. I'm going to house the Photon board and relay in a weather-proof PVC box (the gray stuff at home depot). To that, I will connect another box via two weather-proof PVC pipes. Through one pipe, I will run the hot, neutral, and ground wires to bus bars or terminal blocks. Through the other pipe, I'll then run three leads from the hot bar back to the COM connections on the relays, then three leads from the NO connections on the relays to the three receptacles. I'll have the three pairs of hot leads shrink wrapped.

Electrically, it looks sound. But is doing this up to code? This particular contraption will be in a garage, out of the weather.

Schematic of proposed plan: Schematic of proposed plan

Bus bars (found in electrical service panels) and Terminal/Barrier blocks: Bus bars and Terminal/Barrier blocks

  • You changed your drawing. You need to have the hot feed and returns in the same conduit. The second drawing is NOT up to code. The current flowing to and from a device needs to be in the same conduit. – ArchonOSX Mar 18 '16 at 9:39
  • Good to know. I'll go back to the original schematic. – user208145 Mar 18 '16 at 9:52
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Looks good.

Well thought out and well designed.

I can't think of anything that would be a code violation. Make sure the terminal strips are identified for use with the system voltage and identified for the current of the circuit. Is the Photon board identified for the voltage?

If it is in a garage you don't need a weatherproof enclosure. A simple screw cover junction box will do but would have to be bonded to the equipment ground conductor. If you like the plastic enclosure though then that works too.

Good luck!

  • By "...identified for use with the system voltage and identified for the current of the circuit." do you mean make sure I buy 120V 15A capable strips/bars? I'd prefer bus bars if available and allowed. The photon board uses a 12V, 2A, 2.1mm barrel plug (center positive) wall-wart style adapter. The relay board steps down the voltage to the Photon microcontroller to 3.3V so I only need one power connection for it. I chose weatherproof because I don't know the state of the garage's weatherproof-iness. Thanks. – user208145 Mar 18 '16 at 9:25
  • Yes. All items should be designed for the voltage they will be connected to. If the photon board relays are designed for 120 volts then their terminals are too and that would be the only part that needs to be identified for 120 volt. You changed your drawing and it now is not electrically sound. The hot and return wires need to be in the same conduit. – ArchonOSX Mar 18 '16 at 9:38
  • Thank you for the correction. I've changed the schematic back to the original drawing and changed the text description back. – user208145 Mar 18 '16 at 9:58
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  1. The NEC requires all outlets in a garage to be GFCI protected. Your garage may already be GFCI protected if the outlet was existing.
  2. The whip from the PVC box to the GFCI can be SJ cord.

Other than those small items, totally legit.

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