Adding more panels - DC fed to existing batteries?

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Joeboy
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Re: Adding more panels - DC fed to existing batteries?

#11

Post by Joeboy »

Ah, got ye. I like the powder coating idea to make it unobtrusive. Could always shim it out at the back if using rawlbolt type anchors and it's not off by too much?

A cool wee project to get into by the sounds of it. 8-)
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Oldgreybeard
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Re: Adding more panels - DC fed to existing batteries?

#12

Post by Oldgreybeard »

Joeboy wrote: Sat Aug 20, 2022 10:52 am Ah, got ye. I like the powder coating idea to make it unobtrusive. Could always shim it out at the back if using rawlbolt type anchors and it's not off by too much?

A cool wee project to get into by the sounds of it. 8-)
Plan at the moment (may well change!) is to bolt strut vertically to the wall at each bracket location, packed out as needed to get it level, bolt cantilever arms for the lower (horizontal) support, and use these hinge type variable angle brackets at the top and outboard end, to hold the angled rails:
variable angle bracket.jpg
variable angle bracket.jpg (7.94 KiB) Viewed 1317 times
I'd fit channel covers to the vertical rails, like this stuff:
Channel cover.jpg
Channel cover.jpg (12.46 KiB) Viewed 1317 times
and fit end caps to all the exposed ends. The panel mounting rails can then be fitted to the angled struts and adjusted to get them level. I can get 6m lengths of strut, which will be just about ideal, as I can have rails in one piece with no joins. I think that black powder coated strut should pretty much blend in and be fairly unobtrusive. I need to find a cable management solution that doesn't look out of place, some small black trunking along the wall will probably do the job.
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Joeboy
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Re: Adding more panels - DC fed to existing batteries?

#13

Post by Joeboy »

Oldgreybeard wrote: Sat Aug 20, 2022 11:16 am
Joeboy wrote: Sat Aug 20, 2022 10:52 am Ah, got ye. I like the powder coating idea to make it unobtrusive. Could always shim it out at the back if using rawlbolt type anchors and it's not off by too much?

A cool wee project to get into by the sounds of it. 8-)
Plan at the moment (may well change!) is to bolt strut vertically to the wall at each bracket location, packed out as needed to get it level, bolt cantilever arms for the lower (horizontal) support, and use these hinge type variable angle brackets at the top and outboard end, to hold the angled rails:

variable angle bracket.jpg

I'd fit channel covers to the vertical rails, like this stuff:

Channel cover.jpg

and fit end caps to all the exposed ends. The panel mounting rails can then be fitted to the angled struts and adjusted to get them level. I can get 6m lengths of strut, which will be just about ideal, as I can have rails in one piece with no joins. I think that black powder coated strut should pretty much blend in and be fairly unobtrusive. I need to find a cable management solution that doesn't look out of place, some small black trunking along the wall will probably do the job.
As it so close to the house and acting as a weather canopy (cool idea), the more you matt black/null out the better it will appear. Maybe all the way down to the brackets and bolts, or is that too far?
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Oldgreybeard
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Re: Adding more panels - DC fed to existing batteries?

#14

Post by Oldgreybeard »

Joeboy wrote: Sat Aug 20, 2022 11:27 am As it so close to the house and acting as a weather canopy (cool idea), the more you matt black/null out the better it will appear. Maybe all the way down to the brackets and bolts, or is that too far?

That's the plan, I'll get the whole lot powder coated satin black (local chap can do this for less than it'd cost me to paint it all) and use black cap head screws/bolts. With black end caps and channel covers I reckon it should look OK, although SWMBO is not so sure at the moment! I'm convinced that covering this path will make a huge difference, especially in winter, as it leads from our back door to the wheelie bin store. Being able to get to the bins without having to don foul weather gear when it's raining would make this worth doing, having a couple of kW of panels as well is a bonus.
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Joeboy
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Re: Adding more panels - DC fed to existing batteries?

#15

Post by Joeboy »

Oldgreybeard wrote: Sat Aug 20, 2022 11:39 am
Joeboy wrote: Sat Aug 20, 2022 11:27 am As it so close to the house and acting as a weather canopy (cool idea), the more you matt black/null out the better it will appear. Maybe all the way down to the brackets and bolts, or is that too far?

That's the plan, I'll get the whole lot powder coated satin black (local chap can do this for less than it'd cost me to paint it all) and use black cap head screws/bolts. With black end caps and channel covers I reckon it should look OK, although SWMBO is not so sure at the moment! I'm convinced that covering this path will make a huge difference, especially in winter, as it leads from our back door to the wheelie bin store. Being able to get to the bins without having to don foul weather gear when it's raining would make this worth doing, having a couple of kW of panels as well is a bonus.
That's exactly how I see it. A wonderful twofer! You know you're going to enjoy taking the rubbish out now! :D 8-)
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Oldgreybeard
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Re: Adding more panels - DC fed to existing batteries?

#16

Post by Oldgreybeard »

Any tried using this composite GRP strut? https://www.orbitalfasteners.co.uk/prod ... rp-plastic
Composite strut.jpg
Composite strut.jpg (55.53 KiB) Viewed 1300 times
It's about 1/3rd of the price of stainless, as well as being lighter. Looks to have a reasonable surface finish, too. Wouldn't be able to powder coat it (not conductive) but it would probably take paint OK.
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Joeboy
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Re: Adding more panels - DC fed to existing batteries?

#17

Post by Joeboy »

Oldgreybeard wrote: Sat Aug 20, 2022 12:05 pm Any tried using this composite GRP strut? https://www.orbitalfasteners.co.uk/prod ... rp-plastic

Composite strut.jpg

It's about 1/3rd of the price of stainless, as well as being lighter. Looks to have a reasonable surface finish, too. Wouldn't be able to powder coat it (not conductive) but it would probably take paint OK.
Used it offshore, its good but will bend very much before s/s angle. Might need more bracing than the s/s? We had to add vdm's to brace it enough to stop flexing. I guess it depends on how much 'less is more' that you are looking for?
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Oldgreybeard
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Re: Adding more panels - DC fed to existing batteries?

#18

Post by Oldgreybeard »

Joeboy wrote: Sat Aug 20, 2022 12:11 pm Used it offshore, its good but will bend very much before s/s angle. Might need more bracing than the s/s?
Thanks, that's useful to know. I can mitigate and deflection be just adding more brackets, I think, as it's only the long rails that might tend to deflect a bit under load, the bracket rails will barely see any bending loads as I can bolt the lower rail pretty much inline with the end of the cantilever arm and the upper rail can be fairly close to the upper end of the sloping rail. I was thinking of having four brackets over a 6 metre run, but could easily increase this to five or six, so the unsupported length of the rails would be not be more than maybe 1.5m at most.
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Fintray
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Re: Adding more panels - DC fed to existing batteries?

#19

Post by Fintray »

It might be a bit more flexible but as you are covering it with panels the frames of the panels will increase the overall stiffness.
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Oldgreybeard
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Re: Adding more panels - DC fed to existing batteries?

#20

Post by Oldgreybeard »

Fintray wrote: Sat Aug 20, 2022 12:30 pm It might be a bit more flexible but as you are covering it with panels the frames of the panels will increase the overall stiffness.
TBH, I'm tempted to just buy a length of this composite strut and have a play with it to see how stiff it is. My gut feeling is that it will be fine, as you say. The panels will be a distributed load, don't weigh a lot and the wind loading here would be negligible, as it's on the sheltered side of the house. Same goes for snow loading, never heard of this area getting more than an inch or two.

At roughly £10/metre it's around double the price of galvanised strut, but about 1/3rd the price of stainless, so it seems like a good choice where weight plus a decent surface finish matter. Pity they don't make cantilevers in the same material, but as the load is relatively low I think I could get away with using brackets to make the cantilever arms.
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