Floor box installation

[karn]

So I'm looking for ideas on a better way to install these floor boxes, what we did here was mount the boxes on some strut and screw the strut to some EMT stakes, then filled in the hole with some #57 stone,
Also can anyone tell me if by code I need to ground these PVC boxes (there is a small metal piece in the box with 2 ground screws on it)

 

[Dennis Alwon]

I have seen plastic boxes with ground screws and if I remember correctly the ground area is attached to the threads of where the receptacle screws into. Not sure why it would be necessary other than for an isolated ground setup

 

[Little Bill]

I don't know if those boxes are suitable/listed for a pool junction box but the grounding sounds similar. It states there should be a grounding bar with as many holes as there are conduit entries. Since the OP said there were two ground screws and I see two (at least) conduit entry ports.

Also, I think in Canada plastic boxes have to be grounded/bonded. These boxes could be made to both US and Canada requirements.

 

[karn]

I don't know if those boxes are suitable/listed for a pool junction box but the grounding sounds similar. It states there should be a grounding bar with as many holes as there are conduit entries. Since the OP said there were two ground screws and I see two (at least) conduit entry ports.

Also, I think in Canada plastic boxes have to be grounded/bonded. These boxes could be made to both US and Canada requirements.

There's 4 entry holes, 2 on front side and 2 on back side

 

[ActionDave]

So I'm looking for ideas on a better way to install these floor boxes, what we did here was mount the boxes on some strut and screw the strut to some EMT stakes, then filled in the hole with some #57 stone,
Also can anyone tell me if by code I need to ground these PVC boxes (there is a small metal piece in the box with 2 ground screws on it)

Your set up looks pretty good to me.

I agree with Little Bill, I think the EGC in a plastic box is a Canadian thing.