Inverters in not readily accessible locations and disconnects

[Carultch]

The example is carport canopy columns, used as support structures for inverters. Elevated out of reach of the general public, site personnel would need a ladder to service each inverter.

It is my understanding that for an inverter in such a location needs "comprehensive disconnects" within sight and readily accessible relative to the location of the inverter. So you are up on the ladder, you should be able to reach both AC and DC disconnects without a tool, and without getting off the ladder. Am I understanding this correctly?

The question is, can this disconnect be behind a latched opaque enclosure lid? Provided that the cover is permanently labeled to mark that it is a disconnect. Not a screw cover, but a quick-release latch.

The string inverters I'm specifying only have DC disconnects without a DC combiner, and would thus need an external DC combiner and AC disconnect in addition. I'd like to build a custom enclosure with the combiner fuses and busbars, as well as a DIN-rail mounted AC breaker, to satisfy both requirements in one enclosure. And not have to insert a disconnect through the lid.

 

[mwm1752]

readily accessible does not allow standing on a ladder -

 

[Carultch]

readily accessible does not allow standing on a ladder -

I know that.

My point is, when standing on a ladder to service an inverter, must you also be able to reach both disconnects without climbing down the ladder?

 

[mwm1752]

The readily accessible disconnects are to be within sight of the inverters, the premise of the inverter not being readily accessible is the cause for within sight.

 

[jaggedben]

Well the first part of 690.15 requires disconnecting means from all sources of energization to be "grouped and identified", whether the inverter is readily accessible or not. I think if you put disconnects that are reachable from the ladder then you are definitely meeting the requirement. Maybe you can still meet the requirement if you put them a bit farther away but still in sight, but that's up to the AHJ. I think the purpose of the section is that no one is going to energize equipment you are working on without your knowledge, so if you can fulfill that...

As for your custom enclosure, the 2014 code now requires combiners to be listed, (see 690.4(B)) and 690.31(B) places restrictions on AC and DC in the same enclosure. So I don't think that's a great idea. Latched cover is okay though.

 

[mwm1752]

Well the first part of 690.15 requires disconnecting means from all sources of energization to be "grouped and identified", whether the inverter is readily accessible or not. I think if you put disconnects that are reachable from the ladder then you are definitely meeting the requirement. Maybe you can still meet the requirement if you put them a bit farther away but still in sight, but that's up to the AHJ. I think the purpose of the section is that no one is going to energize equipment you are working on without your knowledge, so if you can fulfill that...

As for your custom enclosure, the 2014 code now requires combiners to be listed, (see 690.4(B)) and 690.31(B) places restrictions on AC and DC in the same enclosure. So I don't think that's a great idea. Latched cover is okay though.

Let me rephrase - If your disconnect is required to be readily accessible per 110.26 then using a ladder to operate such disconnect is non compliant.
Accessible, Readily (Readily Accessible). Capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to actions such as to use tools, to climb over or remove obstacles, or to resort to portable ladders, and so forth.

 

[Carultch]

Let me rephrase - If your disconnect is required to be readily accessible per 110.26 then using a ladder to operate such disconnect is non compliant.
Accessible, Readily (Readily Accessible). Capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to actions such as to use tools, to climb over or remove obstacles, or to resort to portable ladders, and so forth.

I have a panelboard full of AC breakers, at ground level and readily accessible. A breaker dedicated to each inverter.
I have inverters mounted up on columns and not readily accessible. Some of which are within 50 ft and line of sight of the panelboard, some which aren't.

Where does the additional AC disconnect need to be, if at all?
Can it be within a labeled enclosure behind the latched opaque lid?