DC Disconnect AND Rapid Shutdown Switch?

[new2solar2]

If you have a readily accessible rapid shutdown switch located outside of a building, do you still need a DC disconnect switch beside it? Inside, the inverter has a built-in DC Disconnect for the solar panel wires. Technically, the rapid shutdown switch would be safer right, as it reduces the voltage at the panel and wire...as opposed to the dc disconnect which just severs the connection between the panel and inverter.

 

[JoelE]

If you have a readily accessible rapid shutdown switch located outside of a building, do you still need a DC disconnect switch beside it? Inside, the inverter has a built-in DC Disconnect for the solar panel wires. Technically, the rapid shutdown switch would be safer right, as it reduces the voltage at the panel and wire...as opposed to the dc disconnect which just severs the connection between the panel and inverter.

I had the same question! For my inverter there appears to be a physical disconnect at the bottom of it, and a separate remote button for the RSD. I'm also trying to figure out if I can save the cost of a separate DC disconnect box. I'll let you know if I hear back on my thread!

I'm using a Growatt 7600. Which inverter are you using? Sounds like a similar design.

 

[new2solar2]

I had the same question! For my inverter there appears to be a physical disconnect at the bottom of it, and a separate remote button for the RSD. I'm also trying to figure out if I can save the cost of a separate DC disconnect box. I'll let you know if I hear back on my thread!

I'm using a Growatt 7600. Which inverter are you using? Sounds like a similar design.

I'm using the Sol-Ark 15k. In the manual it says that the switch along the side of the inverter to turn off PV source satisfies NEC 240.15. It should also satisfy 690.15 and 690.17, but the question is, does it satisfy 690.13A if the inverter is located inside a utility room?

 

[BearFromFL]

I also would like the answer to this one. It seems that several string inverters are designed to have a DC disconnect at the wires coming in. My system is being planned but is on the opposite side of the house in a utility room from mains service disconnect. My hope is to just run the RDS button next to the main panel. If this does not satisfy the requirement then do I have to run my PV wire from one side the house to the other and then back again? so confused.

 

[Chris72]

I also would like the answer to this one. It seems that several string inverters are designed to have a DC disconnect at the wires coming in. My system is being planned but is on the opposite side of the house in a utility room from mains service disconnect. My hope is to just run the RDS button next to the main panel. If this does not satisfy the requirement then do I have to run my PV wire from one side the house to the other and then back again? so confused.

Me to

 

[Chris72]

Did anyone ever get an answer on this? My question if I can Have RSD with all my other shutdowns and the PV disconnect outside behind my gate.

 

[Chris72]

I talked to my inspector and you indeed need to have both switches readily accessible. So that means you would need to have a PV disconnect and a rapid shutdown switch outside. See attached.

 

[pvgirl]

Readily accessible as defined in code does not require the PV disconnect to be installed outside. Per NEC 2020:

Accessible, Readily (Readily Accessible). Capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to take actions such as to use tools (other than keys), to climb over or under, to remove obstacles, or to resort to portable ladders, and so forth. (CMP-1)​

The initiation device for rapid shutdown is required to be outside and readily accessible only for one-family and two-family dwellings, this is called out specifically and beyond just readily accessible, in 690.12(C).

Requirements of the local utility or other local regulations, may go beyond or differ from the minimum requirements of the NEC.

 

[Chris72]

Readily accessible as defined in code does not require the PV disconnect to be installed outside. Per NEC 2020:

Accessible, Readily (Readily Accessible). Capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to take actions such as to use tools (other than keys), to climb over or under, to remove obstacles, or to resort to portable ladders, and so forth. (CMP-1)​

The initiation device for rapid shutdown is required to be outside and readily accessible only for one-family and two-family dwellings, this is called out specifically and beyond just readily accessible, in 690.12(C).

Requirements of the local utility or other local regulations, may go beyond or differ from the minimum requirements of the NEC.

You are right they don't say outside. There's kind of a gray area there. Readily accessible to who the fire department or me?

 

[pvgirl]

You are right they don't say outside. There's kind of a gray area there. Readily accessible to who the fire department or me?

Readily accessible, without any further requirements, only means that someone can walk up to the disconnect and turn it off, using a key at most. So no special tools needed, not blocked by obstacles, or mounted so high a ladder is needed. It's a pretty low bar to meet.

 

[andyfromlc]

I'm using the Sol-Ark 15k. In the manual it says that the switch along the side of the inverter to turn off PV source satisfies NEC 240.15. It should also satisfy 690.15 and 690.17, but the question is, does it satisfy 690.13A if the inverter is located inside a utility room?

the problem with the pv switch on the inverter...does it need to be adjacent/nearby your mains power so that there is a single location for isolating the solar system. From what I understand as well as the local code enforcers may require that the PV RSD has to be at the panel right near the pv array and not at the inverter which is not near the solar panels.