Advice on system components - EG4 18K

[Max de Arriz]

Hello there,

I hope all is well in your world. I'm a total amateur here, but I know enough to avoid basic electrical fires. EG4 makes a sweet PDF. I am interested building my own system.

Here is my big question: What would you use fore the components below (image below)?

1. 2 Pole - 3 Position manual transfer switch. (I saw a pretty cool 3 position breaker by GE) GE Breaker f@ Home depot
2. PV interactive 2 pole fused disconnect.
3. 200A Main Service breaker (I assume a stand alone box?)
4. A Feeder Tap (Is this more or less a bus bar?)
5. Feeder Tap Breaker (I kind of took this is mean a regular ole 200A breaker)

Thank you so much for your help!

Best,
Max

 

[seatosummit]

Hey Max -

Similar position as you trying to assemble a bill of materials.

For the 200A main service disconnect, you can use something like this that also has an accommodation for a meter socket.

The diagram references a couple different feeder tap options. I personally have experience with Polaris taps. Fundamentally they are bonding devices. The NEC has a whole set of rules around how you can use them. I found this video to be fairly helpful. Especially if you have a cup of coffee.

I started a similar thread to ask about recs on protection off of the feeder tap. I would like to combine both of those OCPD / disconnects into a single enclosure, if possible. The fact that the PV side says fused makes me wonder if that is literal, or if a breaker is adequate.

I looked at the same transfer switch. Would like to find a less expensive one given the relative simplicity of the device??

Best of luck.

Austin

 

[unexpected]

For others that find this thread, I want to note something that took me an hour to figure out:
The "PV Interactive System 2-pole Fused Disconnect" refers to a
"2-pole fused disconnect" for the "PV Interactive System", where the NEC Handbook defines a PV interactive system as "A solar PV system that operates in parallel with and may deliver power to an electrical production and distribution network..

If you are like me and read "interactive" as a function, then you will get really lost for a bit. The
Square D 200 Amp 2-Pole Fusible General-duty Enclosed Circuit Breaker Disconnect is a reasonable option for this compoent

 

[blrmaker]

So glad I found this thread. Thank you! I was wondering about the feeder tap, if it is a brand new build would a bus bar suffice rather than the feeder tap (adding to an existing system)? We are in process of a complete new build home and I am working with the electrical contractor to incorporate the AC side of the system per diagram 4.5. I keep searching this forum for the components that will be needed.

 

[mciholas]

The "PV Interactive System 2-pole Fused Disconnect" refers to a "2-pole fused disconnect" for the "PV Interactive System", where the NEC Handbook defines a PV interactive system as "A solar PV system that operates in parallel with and may deliver power to an electrical production and distribution network..

What purpose does this PV disconnect serve?

If you pull it, everything in the diagram is still hot except the few wires from the disconnect to the inverter. The inverter will run the downstream power from batteries and solar.

If you leave the disconnect in place but hit the RSD, the inverter stops feeding the grid and everything downstream of it shuts off. The direct grid stuff still is hot but the disconnect doesn't shut that off.

This feels like some latent code requirement that doesn't make sense in the system. The PV disconnect doesn't really turn anything off. The RSD actually turns off the energy properly and the PV disconnect doesn't add anything meaningful to that.

One always hopes there is some logical basis to the code, but I don't see it in this case and I hate putting in useless things.

Mike C.