Installer unfriendly design of inverter

[BillK-AZ]

Equipment: Solectria PVI 13kW inverter with front facing disconnects and internal DC Combiner

These inverters use external safety switches for the AC and DC disconnects. One option is to specify that the disconnects face forward, rather than to the sides. If the disconnects were facing the sides, clearance would be needed on the sides.

When the internal DC Combiner option is specified, the fuseholders and terminal block are crammed into the bottom area of the DC disconnect and almost cover the only rear concentric knockout that has a matching access hole in the bracket that mounts the disconnect to the inverter.

Since this is a concentric knockout and the voltage is over 250 volts, the conduit must be bonded with a ground bushing. But, the access to the concentric knockout is such that it is not possible to tighten the lock screw on the ground bushing. The installer has to carefully remove the factory installed fuseholders in order gain access to the screw. They should make the designers actually install these inverters.

In hindsight, it would have been better to have designed the system with a separate DC Combiner.

 

[Zee]

I feel your pain. Aaaah.... the joy of grounding bushings. And awkward spaces, which they all are, when it comes to gr. bshngs. I own one tool that I call the "MAGIC TOOL". Don't laugh. It is. This has saved my sanity over many grounding bushings. It is a tiny, Husky ratcheting wrench, I guess, but really it is a tiny right angle screwdriver (offset screwdriver) that takes any standard driver bit with a 1/4" hexagonal shank. It also ratchets every 7 degrees to tighten in those impossible areas. And you can get it at...Home Despot. Less than 20 bucks - worth about what i paid for the MC plugmaker.

 

[jaggedben]

The 'magic tool' for me is similar. A 'speedwrench' that is 1/4" on one end and 5/16" on the other, and I can take the different bits out of my 11-in-1 and turn it into a little right angle driver. Still a pain sometimes, but doable.

A buddy of mine had a Craftsman (I think?) one that takes standard 1/4" bits. Also has a little thumbwheel for spinning the spit when you don't need torque, which is a really good design. (Not like the ones at Ace Hardware where the bits are custom to the tool and if you lose them you gotta buy the whole set to replace.) Also the direction latch was 'protected' if you know what I mean. Best design I've seen, been meaning to look for one of those but haven't gotten it yet. It was also great for tightening lugs underneath panels with minimal roof clearance.

 

[Zee]

What a difference a good tool makes. :roll:MIne is 1/4 and 5/16 on each end, also.