Attaching insulated bus bar to metal box
Installing Midnite Solar short bus bars like these: in aluminum breakers box - Big Baby Box from the same Midnite, like this: One bus bar is shown on the photo, and there are mounting...
Forum Discussion
Great minds think alike. I thought about rivets this morning, but there are problems.
Insulator (nut in the hole is explained below):
Click For Full-Size Image.
Hole in the "foot" (left on the photo) is 0.206" as per drawing. 3/16" rivet needs a hole 0.204", good enough.
Here is the problem: rivet in plastic needs a washer. Then total material thickness will be 0.3825", and rivet head 0.39". Hole from the top is 0.375". Ops - need a thin rivet 5/32" with 0.33" head.
Now, plan B: Hex nut #10 has OD 0.375", I put it easily in the hole from the top (right on the photo) and with some effort I can push it all the way in. Machine screw from the back, nut in the hole (as on the photo), 1/4" clearance from the nut to metal bus bar. And glue under the insulator.
There is already one screw head on the back of the box - photo below.
Or plan A: rivet 5/32"=0.16" in 0.2" hole. And glue.
Q 1: What do you guys think, A or B?
(Why not just glue - because the insulator foot is hollow, it rests on thin perimeter wall with 2 tiny pegs).
Back of the box:
Click For Full-Size Image.
Red circle are pre-drilled holes for insulated bus bar - for tapping screws and 2 pegs. See the head of Ground lug screw above? Box mounting screws are recessed so there are "bulges" on the back, but the screw head still sticks out beyond those bulges.
Q 2: If I use bolts and nuts, what if I file the heads off by about 1/3, making them lower profile?
Q 3: There are 3 more holes in the back - what are those for?
Q 4: With insulated bus there are included 4 machine screws #10-32, half-inch long. They are not set screws. Have no clue what those are for, but this is how I came to Plan B. What are they for?
I haven't discarded this plan yet, this is what manufacturer recommends. It's just odd that insulator tapping screws will penetrate the plywood wall behind.
Insulator (nut in the hole is explained below):
Hole in the "foot" (left on the photo) is 0.206" as per drawing. 3/16" rivet needs a hole 0.204", good enough.
Here is the problem: rivet in plastic needs a washer. Then total material thickness will be 0.3825", and rivet head 0.39". Hole from the top is 0.375". Ops - need a thin rivet 5/32" with 0.33" head.
Now, plan B: Hex nut #10 has OD 0.375", I put it easily in the hole from the top (right on the photo) and with some effort I can push it all the way in. Machine screw from the back, nut in the hole (as on the photo), 1/4" clearance from the nut to metal bus bar. And glue under the insulator.
There is already one screw head on the back of the box - photo below.
Or plan A: rivet 5/32"=0.16" in 0.2" hole. And glue.
Q 1: What do you guys think, A or B?
(Why not just glue - because the insulator foot is hollow, it rests on thin perimeter wall with 2 tiny pegs).
Back of the box:
Red circle are pre-drilled holes for insulated bus bar - for tapping screws and 2 pegs. See the head of Ground lug screw above? Box mounting screws are recessed so there are "bulges" on the back, but the screw head still sticks out beyond those bulges.
Q 2: If I use bolts and nuts, what if I file the heads off by about 1/3, making them lower profile?
Q 3: There are 3 more holes in the back - what are those for?
Q 4: With insulated bus there are included 4 machine screws #10-32, half-inch long. They are not set screws. Have no clue what those are for, but this is how I came to Plan B. What are they for?
BruceMc wrote:
Depending on the strength of the material, 1/16th inch aluminum will probably hold those 2 #10 screws just fine.
I haven't discarded this plan yet, this is what manufacturer recommends. It's just odd that insulator tapping screws will penetrate the plywood wall behind.
