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MT Solar mount review

Zwy

Solar Wizard
Joined
Jan 3, 2021
Messages
5,685
Location
Timbuktu, IA
I finished installing my array this fall and following is a review of this mount and install. I purchased the MT Solar Top of the Pole mount in a 16 panel configuration. When purchasing the mount, you go to the MT Solar website, there is a calculator where you input panel sizes, number of panels, soil type, local rated wind speed, and snowload. MT Solar will then review your inputs and determine what mount will be required using an engineering program that is commonly used for signage. You will receive an engineering report so you can submit it to local building inspector if required, around here there aren't any codes but an insurance company may require documentation. As for wind speed rating, that can be found thru government websites as can snow load ratings. Part of the reason I liked this mount was the ability to assemble on the ground, then raise it up to allow for mowing the grass under it.

Cost was $6800 delivered to closest Fed Ex freight terminal about an hour away. Pallets were well made, nicely wrapped in the type of fabric commonly found over lumber. Not too heavy, came on 2 pallets and I have a forklift so wasn't a problem moving them. These mounts arrived mid February last year, took about 6 weeks for them to build it after I paid them for it. I stored it in my shed until late September. The paint used still had the strong odor when I went to install and I had removed the wrapping to keep moisture from accumulating. The paint is not catalyzed obviously and the paint job was not exceptional coverage, I will have to touch up that mount next year in spots. The 2 poles were sourced locally at a cost of $1800 so the total was $8600 plus 3.5 yards of concrete.

These require a footing, their specs were 7.5 feet deep x 36 diameter hole. I had a cement contractor that never showed, I ended up purchasing my own auger and drilling the holes myself. I own a transit and drilled the holes to the right depth and had cut the pipe to the required length beforehand. If I had to do it again, I'd go as deep as my auger can go with one extension. Poles were centered and braced in hole, it helps to have a board against the pole and a come along or strap tightened to pull the pole tight to the board. Filling the hole doesn't require much cement, takes about 1.75 yards per hole. Conduit was run before cement was poured so lawnmowers and other things won't damage the conduit. Solar mount bracing.jpg

Next was installing the mount, basically it is a saddle around the pole. A chain hoist is attached at the top of the pole with a pocket mount they send which fits inside the pipe. The bracket for the chain hoist can be purchased but I had a slightly larger chain hoist and wanted to ensure it would fit so I fabricated my own. The pocket they send remains in the pole, it provides part of the cap for the pipe. After the saddle is hanging, it is a frame made from square tubing bolted on each side with a 4 inch pipe for the pivot. The tilt screws are installed at this time, it is important to get the angle the same or you will think the frame is twisted as you assemble it. They don't tell you this, I learned it the hard way. Then it is I beam pieces which are bolted together and they have adjusting screws to cover the tolerance between sections to get it straight. It would be easier to have one long length of I beam, remember this is you want to fabricate one. Adjusting the beams with a string in two directions was a pain.Solar mount frame.jpg

Once the frame is assembled, the Tamarak rails are installed using the supplied clips. The rails are installed and this is where my first snag appeared. The panels were 530W which are larger than a standard 72 cell. Panels are 89.25L x 44.2W. MT Solar knew this and had spec'd out the correct rail length but it seems packaging didn't include the needed extensions and the required splices and hardware. Mt Solar handled it well, they sent out what I needed right away. Next I found they didn't send any of the nuts and bolts for the splices on the long rail sections either, so another delay of about 4 days. Solar mount Tamarack.jpg


Panel installation was easy as the mount is close to the ground. On one row, there will be a space for each pole sticking thru and only one panel would need to be installed after raising the array. Slide the panels in line and add the new one on the end by sliding it in. Do not attempt to install the one panel in between the other panels. I again learned the hard way after the nut for the fastener fell down inside the rail. Run your wires between panels and install all the wire holders before raising the array.

Raising was simple, I did it by myself by raising one side then the other alternating. You will want a safety chain in place so you can easily rehook the hoist as you go higher and in case something breaks it might slow things down enough so it won't hurt so bad when the heavy array crushes you to death. :) Raising solar array.jpg

Two of the reasons I wanted a tilting mount was snow and lower sun on the horizon in the winter. With the tilting mount, I eliminate the problem of snow remaining on panels for several days and as the array is not very large wattage, I wanted some maximization of yield in winter. Whether this was cost effective is up for debate but for my usage and area to install I felt it was the best choice. I also wanted to be able to mow under this and also wanted to be able to pile some snow in winter ahead of the array if I needed the room. This is 60 degree tilt, at winter solstice it will be at 65 degrees tilt. I use a simple electronic protractor now for setting tilt, eventually I will make a pointer on each pole. MT Solar mount.jpg

Solar array finished.jpg

Pros for MT Solar was support was good, they respond quickly and they run things thru an engineering platform and provide needed documentation if you need it. Packaging was good. They have several videos showing install and those are helpful. Tilt mechanism works well, harder to move to a lower angle than moving to a higher angle. The tilt screws could probably be easily adapted for single axis tracker with a small dc motor if desired.

As for cons, the I beam assembly was a pain but not that difficult. As I stated, if you want to build something like this, one continuous length would work well, I beam can be purchased up to 40 foot length. Paint finish was substandard, I was not impressed. These things are heavy, it takes some effort to raise. The tilt screw mounting is close to the pivot, this allows greater range but can lead to some wiggle at the outer edges of the array in high winds. Screw is mounted behind the pole. it actually would be better ahead of the pole offset to one side and a longer screw used. This would lessen the wiggle in high variable winds.

Would I purchase another mount from MT Solar? Not sure at this point. If you're handy at fabrication and have the equipment like I have and know how to weld, then I'd say build your own. The Skyrack 2.0 costs much less but is not very high off the ground unless they can custom build it. The Skyrack would be less than 1/2 the cost for the 16 panel array,(most likely would have to use their 20 panel mount due to pv module size) but it would be higher priced for custom application for my pv modules. I would only install the Skyrack using footings; around here I see many arrays with driven pilings but the clay in the ground here combined with frost that commonly goes down to a depth of 6 feet heaves arrays and you see after a few years a roller coaster.

Would I install anything other than tilting array? After having the first snow here and observing the various fixed tilt arrays in the area after that wet snow, I'd say the tilting array is worth the money, especially if you are off grid and need to maximize yield.
 
Thanks for the review! I've heard good things about the MT Solar racking, but a lot of that is along the lines of "they're they only people who do this", rather than "they're great!" So it's good to hear this first hand report.
 
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Looks good. Those panels are huge, I imagine they were a bear getting put on. How has it handled snow and wind loads? The thought of 7.5ft footings blows my mind, you must be waay up north. How has the output been from the panels? So, I guess you have a string of 8 going to each of your EG4's? Just curious as to how you grounded your mount and panels. Are they grounded at the array or back to the grounding rod at the service pole/panel?

We had 8 445W Canadian Solar bifacials, and they were 63lb apiece, so I had to have help. My wife held them on the rails to keep them from sliding while I fastened them on. We've had three days of 50mph+ wind gusts, and the ground mount has held up pretty well.
 
Looks good. Those panels are huge, I imagine they were a bear getting put on.
Put all but the last one on before raising it up to the top of the poles. I have an off road forklift anyway, double mast and gets me up to 28 feet so sliding the panels over wasn't a problem.

How has it handled snow and wind loads?

I tilt to 65 degrees off horizontal in winter. It's set at 47 degrees now with the spring equinox. Summer will be 30 degrees. Wind has been handled well, I do see where it wiggles, mostly due to the screw for adjustment is fairly close to the pivot. This summer I plan to make a brace that reaches farther out that will be notched for the 3 different angles for the solstice's and equinoxes. Makes it easy to get the right angle and provide more support in high winds.

Snow doesn't lay on panels at 65 degrees off horizontal.

The thought of 7.5ft footings blows my mind, you must be waay up north.

Frost here goes down 6 feet, all water lines are buried at least 6 feet deep here. Part of the reason for the depth is the leverage of the pole above ground. MT Solar does provide a engineering report. Next time I'd do 8.5 feet.

How has the output been from the panels? So, I guess you have a string of 8 going to each of your EG4's?

I max out the MPPT in each EG4 at 4Kw with the 8 panels per string. I needed to get voltage high as the array is 420 feet one way from house. I can add more PV if I decide to down the road as I'm only using one MPPT per EG4. VOC will be 422V at -30F.

Half cut cells and panel efficiency was stated as over 20%. I'm pretty impressed with the panels. They aren't available anymore but I think there might be a 540W available. It's the sweet spot for the EG4, somewhere close to 500W.

Just curious as to how you grounded your mount and panels. Are they grounded at the array or back to the grounding rod at the service pole/panel?

There is a ground wire ran from OVP in junction box on pole. This is not tied to array. Array mount and poles are ground thru the structure.

We had 8 445W Canadian Solar bifacials, and they were 63lb apiece, so I had to have help. My wife held them on the rails to keep them from sliding while I fastened them on. We've had three days of 50mph+ wind gusts, and the ground mount has held up pretty well.
With adjustable tilt, I could lay the rails horizontal to install panels. Wife and daughter helped set panels on while it was at ground level. Pretty slick actually. If I do add more PV, I have a design I can copy to an extent. I'd use one long piece of I beam for example, make the screw longer or double stage. I'd use 7" oil well pipe for poles, can buy that cheap instead of the 6" SCH 80. I do like the Tamarack rails, but really any rail mount will work.
 
There is a ground wire ran from OVP in junction box on pole. This is not tied to array. Array mount and poles are ground thru the structure.
Sorry I'm not getting what you mean. What is OVP?

Are you saying the metal of the mount itself is the ground? And that you are not running a ground wire back to your service panel grounding rod? I'm assuming all the panel frames are tied together and grounded?

Those small arms on the side view control the angle set up? They look a little bit thin, but I'm sure there's other ways of keeping things locked in place after they're adjusted. I guess if you have the panel rack at just the right height on the poles, it's a matter of leverage on how much it can be adjusted. Are you looking into adding another array?

I can get your argument for going with an adjustable array especially if you're farther north. You need to maximize as much irradiation in the winter as you can get. I considered making an adjustable mount, but it probably doesn't make it worth it in my location. I calculated the best overall angle for my latitude was about 32 degrees. Thru some trig calcs, I figured the back posts needed to be 4ft above level, and distance between front and back posts had to be about 7ft. And I had to take into account the slope of my yard. After all the work the final angle was about 33.5 degrees. Close enough for a 28ft long ground mount.
 

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Sorry I'm not getting what you mean. What is OVP?

Over voltage protection using a surge protector.


Are you saying the metal of the mount itself is the ground?

Similar to an ufer ground, the concrete and pole in the concrete is the ground.

And that you are not running a ground wire back to your service panel grounding rod?

There is one ground wire running back from the surge protector. It is not tied to the mount.

I'm assuming all the panel frames are tied together and grounded?

Tied and grounded thru the structure.

Those small arms on the side view control the angle set up? They look a little bit thin, but I'm sure there's other ways of keeping things locked in place after they're adjusted.

You might be looking at the crank for the screw. The thin looking pipe at the rear is the crank handle which is long enough to reach up to the screw. This photo shows just the screw in the back without the crank extension.

solar-mount-frame-jpg.122106

I guess if you have the panel rack at just the right height on the poles, it's a matter of leverage on how much it can be adjusted. Are you looking into adding another array?

I might put up an array for my shop. Or add more PV for winter.

I can get your argument for going with an adjustable array especially if you're farther north. You need to maximize as much irradiation in the winter as you can get. I considered making an adjustable mount, but it probably doesn't make it worth it in my location. I calculated the best overall angle for my latitude was about 32 degrees. Thru some trig calcs, I figured the back posts needed to be 4ft above level, and distance between front and back posts had to be about 7ft. And I had to take into account the slope of my yard. After all the work the final angle was about 33.5 degrees. Close enough for a 28ft long ground mount.
Biggest thing here is snow, panels don't produce covered in snow. Check out the photos I posted this winter for various systems in my area. https://diysolarforum.com/threads/new-system-whole-house-near-lacrosse-wi.54585/post-701156
 
I finished installing my array this fall and following is a review of this mount and install. I purchased the MT Solar Top of the Pole mount in a 16 panel configuration. When purchasing the mount, you go to the MT Solar website, there is a calculator where you input panel sizes, number of panels, soil type, local rated wind speed, and snowload. MT Solar will then review your inputs and determine what mount will be required using an engineering program that is commonly used for signage. You will receive an engineering report so you can submit it to local building inspector if required, around here there aren't any codes but an insurance company may require documentation. As for wind speed rating, that can be found thru government websites as can snow load ratings. Part of the reason I liked this mount was the ability to assemble on the ground, then raise it up to allow for mowing the grass under it.

Cost was $6800 delivered to closest Fed Ex freight terminal about an hour away. Pallets were well made, nicely wrapped in the type of fabric commonly found over lumber. Not too heavy, came on 2 pallets and I have a forklift so wasn't a problem moving them. These mounts arrived mid February last year, took about 6 weeks for them to build it after I paid them for it. I stored it in my shed until late September. The paint used still had the strong odor when I went to install and I had removed the wrapping to keep moisture from accumulating. The paint is not catalyzed obviously and the paint job was not exceptional coverage, I will have to touch up that mount next year in spots. The 2 poles were sourced locally at a cost of $1800 so the total was $8600 plus 3.5 yards of concrete.

These require a footing, their specs were 7.5 feet deep x 36 diameter hole. I had a cement contractor that never showed, I ended up purchasing my own auger and drilling the holes myself. I own a transit and drilled the holes to the right depth and had cut the pipe to the required length beforehand. If I had to do it again, I'd go as deep as my auger can go with one extension. Poles were centered and braced in hole, it helps to have a board against the pole and a come along or strap tightened to pull the pole tight to the board. Filling the hole doesn't require much cement, takes about 1.75 yards per hole. Conduit was run before cement was poured so lawnmowers and other things won't damage the conduit. View attachment 122105

Next was installing the mount, basically it is a saddle around the pole. A chain hoist is attached at the top of the pole with a pocket mount they send which fits inside the pipe. The bracket for the chain hoist can be purchased but I had a slightly larger chain hoist and wanted to ensure it would fit so I fabricated my own. The pocket they send remains in the pole, it provides part of the cap for the pipe. After the saddle is hanging, it is a frame made from square tubing bolted on each side with a 4 inch pipe for the pivot. The tilt screws are installed at this time, it is important to get the angle the same or you will think the frame is twisted as you assemble it. They don't tell you this, I learned it the hard way. Then it is I beam pieces which are bolted together and they have adjusting screws to cover the tolerance between sections to get it straight. It would be easier to have one long length of I beam, remember this is you want to fabricate one. Adjusting the beams with a string in two directions was a pain.View attachment 122106

Once the frame is assembled, the Tamarak rails are installed using the supplied clips. The rails are installed and this is where my first snag appeared. The panels were 530W which are larger than a standard 72 cell. Panels are 89.25L x 44.2W. MT Solar knew this and had spec'd out the correct rail length but it seems packaging didn't include the needed extensions and the required splices and hardware. Mt Solar handled it well, they sent out what I needed right away. Next I found they didn't send any of the nuts and bolts for the splices on the long rail sections either, so another delay of about 4 days. View attachment 122107


Panel installation was easy as the mount is close to the ground. On one row, there will be a space for each pole sticking thru and only one panel would need to be installed after raising the array. Slide the panels in line and add the new one on the end by sliding it in. Do not attempt to install the one panel in between the other panels. I again learned the hard way after the nut for the fastener fell down inside the rail. Run your wires between panels and install all the wire holders before raising the array.

Raising was simple, I did it by myself by raising one side then the other alternating. You will want a safety chain in place so you can easily rehook the hoist as you go higher and in case something breaks it might slow things down enough so it won't hurt so bad when the heavy array crushes you to death. :) View attachment 122108

Two of the reasons I wanted a tilting mount was snow and lower sun on the horizon in the winter. With the tilting mount, I eliminate the problem of snow remaining on panels for several days and as the array is not very large wattage, I wanted some maximization of yield in winter. Whether this was cost effective is up for debate but for my usage and area to install I felt it was the best choice. I also wanted to be able to mow under this and also wanted to be able to pile some snow in winter ahead of the array if I needed the room. This is 60 degree tilt, at winter solstice it will be at 65 degrees tilt. I use a simple electronic protractor now for setting tilt, eventually I will make a pointer on each pole. View attachment 122109

View attachment 122116

Pros for MT Solar was support was good, they respond quickly and they run things thru an engineering platform and provide needed documentation if you need it. Packaging was good. They have several videos showing install and those are helpful. Tilt mechanism works well, harder to move to a lower angle than moving to a higher angle. The tilt screws could probably be easily adapted for single axis tracker with a small dc motor if desired.

As for cons, the I beam assembly was a pain but not that difficult. As I stated, if you want to build something like this, one continuous length would work well, I beam can be purchased up to 40 foot length. Paint finish was substandard, I was not impressed. These things are heavy, it takes some effort to raise. The tilt screw mounting is close to the pivot, this allows greater range but can lead to some wiggle at the outer edges of the array in high winds. Screw is mounted behind the pole. it actually would be better ahead of the pole offset to one side and a longer screw used. This would lessen the wiggle in high variable winds.

Would I purchase another mount from MT Solar? Not sure at this point. If you're handy at fabrication and have the equipment like I have and know how to weld, then I'd say build your own. The Skyrack 2.0 costs much less but is not very high off the ground unless they can custom build it. The Skyrack would be less than 1/2 the cost for the 16 panel array,(most likely would have to use their 20 panel mount due to pv module size) but it would be higher priced for custom application for my pv modules. I would only install the Skyrack using footings; around here I see many arrays with driven pilings but the clay in the ground here combined with frost that commonly goes down to a depth of 6 feet heaves arrays and you see after a few years a roller coaster.

Would I install anything other than tilting array? After having the first snow here and observing the various fixed tilt arrays in the area after that wet snow, I'd say the tilting array is worth the money, especially if you are off grid and need to maximize yield.
Great post, very informative, thank you.
 
@Zwy What panels did you use?
JA Solar 530W

I purchased from San Tan for $4,530 including truck freight. Price was $269 each plus freight. These are half cell panels. I see A1 has the same and similar, the 530W is $225. Be aware these are slightly bigger than a standard 72 cell panel.

I would purchase these again, very well made panel.
 
JA Solar 530W

I purchased from San Tan for $4,530 including truck freight. Price was $269 each plus freight. These are half cell panels. I see A1 has the same and similar, the 530W is $225. Be aware these are slightly bigger than a standard 72 cell panel.

I would purchase these again, very well made panel.
I like half cell/144 panels myself. I ended up with a pallet of 35 Canadian Solar 400w bifacials (using 34 on my array with a spare stashed away) this spring for something like 46.8¢/W. So while not quite as power dense as those 530’s the cost was right. They’re big and heavy too, 61# I think and 84”x 41 3/8”, but installed on my Sinclair Sky Rack 2.0 they do well.
 
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