Hi folks, Ive just mounted a Redarc 180w panel on the roof of my new Toyota HiAce.
I installed it last night and drove today with what sounded like a bad French horn player sitting on the roof whenever I got up to about 80kmh !
The din was/is quite horrendous !
The panel itself is 35mm thick and Ive placed it about 90mm behind the Toyota roof bars (40mm thick)
Why did you mount it central inside the two roof bars you ask, Im a ceramic tiler, I cant help it !
Does anyone have suggestions on how to eliminate the howling ? Thinking now that maybe I should just move it toward the front bar? Im hoping someone has had this experience and found the cure to share with me
Any flat straps up there too as they make very loud noises
Craig1 said
09:38 AM Aug 24, 2021
Can you create a tilt on panel, relative to roof, doesnt need a lot.
Whenarewethere said
09:59 AM Aug 24, 2021
The flat straps are easy to solve. Use the same principle as Burj Khalif 828 metre tall building. If you look at the height of all the sub towers, they spiral in height upward. So the wind spills in one direction upwards.
Put half a twist in flat strap tie downs & they will shut up!
Second issue, if you blow over the end of a tube or two narrow parallel edges you will get a sound. There is a gap between the roof crossbars & the solar panel. You need to make the front edge of the 35mm thick aluminium extrusion, rounded. The same for rear facing edge of the solar panel.
If there are any gaps on the underside of the crossbars, fill them in.
Another option is to put a chevron pattern on the top of the crossbar. This helps spill the air to one side so the air doesn't oscillate.
PS. If you want a quiet van with the bonus of thermal insulation put in acoustic insulation. There is a thread on this in Hints tips and great ideas.
Northernblue said
05:16 PM Aug 24, 2021
Tony LEE wrote:
Any flat straps up there too as they make very loud noises
Yes, everything starts to add up !
Northernblue said
05:21 PM Aug 24, 2021
Craig1 wrote:
Can you create a tilt on panel, relative to roof, doesnt need a lot.
Hi Craig1, I understand you.
I was trying to hide it behind the front bar though, so I can still put things up on the roof racks (the panel sits 3-5mm below the top of the bar, so I can "carefully" still place stuff on the roof)
Northernblue said
05:27 PM Aug 24, 2021
Whenarewethere wrote:
The flat straps are easy to solve. Use the same principle as Burj Khalif 828 metre tall building. If you look at the height of all the sub towers, they spiral in height upward. So the wind spills in one direction upwards.
Put half a twist in flat strap tie downs & they will shut up!
Second issue, if you blow over the end of a tube or two narrow parallel edges you will get a sound. There is a gap between the roof crossbars & the solar panel. You need to make the front edge of the 35mm thick aluminium extrusion, rounded. The same for rear facing edge of the solar panel.
If there are any gaps on the underside of the crossbars, fill them in.
Another option is to put a chevron pattern on the top of the crossbar. This helps spill the air to one side so the air doesn't oscillate.
PS. If you want a quiet van with the bonus of thermal insulation put in acoustic insulation. There is a thread on this in Hints tips and great ideas.
Hi WAWT, That was why I've used angle to mount the panel on because I knew that tube would want to sing, I'm not overly confident that the angle will last forever, but Ill keep an eye on it for any metal fatigue.
Nice drawing too.
Northernblue said
05:34 PM Aug 24, 2021
After thinking about my OCD in placing the panel exactly centre between the two roof bars last night, I got my butt into gear this morning and moved the panel forward against the front bar... success !!! I had a nice quiet drive to work today, the french horn player is nothing but a bad memory
Next Tuesday/Wednesday the wiring will be done and I'll have cold water and beers again.
Thanks for your thoughts people.
Whenarewethere said
06:02 PM Aug 24, 2021
Make sure you calculate the wire resistance for the total length of + & - no point throwing away amps from the solar panel, then having to do wiring again.
Northernblue said
06:31 PM Aug 24, 2021
Whenarewethere wrote:
Make sure you calculate the wire resistance for the total length of + & - no point throwing away amps from the solar panel, then having to do wiring again.
Thats all handballed to my auto elec WAWT, I'll just hand over the money and whatever else he demands
He's done all my auto stuff for 20 years, knows his stuff and will be putting in Redarc (hence his bloody prices !)
I think he said I'm getting 2 x 120Ah AGM's and 40A Redarc BCDC and a couple of oulets and a voltmeter.
The BCDC will be mounted on the side wall of the van between the sliding door and rear and behind the vehicle shelving unit, with a run to the battery of about 300/500mm.
He recons the panel on its own should exceed the fridge consumption, but i can squeeze another two panels onto the roof if I wanted...
Those eliptical bars would be a bit quieter Id guess, and I see what youve done with the roll over, nice job, is it your design or factory option ? The HiAce bars are essentially square, I took the end caps out of the bars on my old van (09 model) and that whistled too, until I hurriedly put them back in.
Whenarewethere said
10:28 PM Aug 24, 2021
I lowered my panels 50mm between the crossbars. They don't get any bugs on them... or sun!
Northernblue said
10:33 PM Aug 24, 2021
Whenarewethere wrote:
I lowered my panels 50mm between the crossbars. They don't get any bugs on them... or sun!
No problems with bats either ?
Looks a neat set out.
-- Edited by Northernblue on Tuesday 24th of August 2021 10:35:11 PM
Whenarewethere said
11:35 PM Aug 24, 2021
I had a roof platform but chucked it out & replaced it with 2 additional crossbars, so 4 in total, with a net weight saving of 16kg.
Like you I have bought quality solar panels. It's not worth buying the cheap rubbish with utterly deceitful figures that even a pork barrel would fail to deliver!
Craig1 said
08:23 AM Aug 25, 2021
I had square bars on BT50, these are Rhino and have a curve as well. So after a mate folded my custom 3mm plate mounts I had a big rubber hammer job to get the top edge down on to the bar. Front plate is about 10mm deeper. Pretty quiet. The square ones were ok though.
Whenarewethere said
09:07 AM Aug 25, 2021
I went to an aluminium fabricator & got them to bend up two 10 x 50mm flat bar sections to fit between the crossbars. It's not that expensive to get something made specifically to your requirements.
Hi folks, Ive just mounted a Redarc 180w panel on the roof of my new Toyota HiAce.
I installed it last night and drove today with what sounded like a bad French horn player sitting on the roof whenever I got up to about 80kmh !
The din was/is quite horrendous !
The panel itself is 35mm thick and Ive placed it about 90mm behind the Toyota roof bars (40mm thick)
Why did you mount it central inside the two roof bars you ask, Im a ceramic tiler, I cant help it !
Does anyone have suggestions on how to eliminate the howling ? Thinking now that maybe I should just move it toward the front bar?
Im hoping someone has had this experience and found the cure to share with me
Cheers
The flat straps are easy to solve. Use the same principle as Burj Khalif 828 metre tall building. If you look at the height of all the sub towers, they spiral in height upward. So the wind spills in one direction upwards.
Put half a twist in flat strap tie downs & they will shut up!
Second issue, if you blow over the end of a tube or two narrow parallel edges you will get a sound. There is a gap between the roof crossbars & the solar panel. You need to make the front edge of the 35mm thick aluminium extrusion, rounded. The same for rear facing edge of the solar panel.
If there are any gaps on the underside of the crossbars, fill them in.
Another option is to put a chevron pattern on the top of the crossbar. This helps spill the air to one side so the air doesn't oscillate.
PS. If you want a quiet van with the bonus of thermal insulation put in acoustic insulation. There is a thread on this in Hints tips and great ideas.
Yes, everything starts to add up !
Hi Craig1, I understand you.
I was trying to hide it behind the front bar though, so I can still put things up on the roof racks (the panel sits 3-5mm below the top of the bar, so I can "carefully" still place stuff on the roof)
Hi WAWT, That was why I've used angle to mount the panel on because I knew that tube would want to sing, I'm not overly confident that the angle will last forever, but Ill keep an eye on it for any metal fatigue.
Nice drawing too.
After thinking about my OCD in placing the panel exactly centre between the two roof bars last night, I got my butt into gear this morning and moved the panel forward against the front bar... success !!!
I had a nice quiet drive to work today, the french horn player is nothing but a bad memory
Next Tuesday/Wednesday the wiring will be done and I'll have cold water and beers again.
Thanks for your thoughts people.
Make sure you calculate the wire resistance for the total length of + & - no point throwing away amps from the solar panel, then having to do wiring again.
Thats all handballed to my auto elec WAWT, I'll just hand over the money and whatever else he demands
He's done all my auto stuff for 20 years, knows his stuff and will be putting in Redarc (hence his bloody prices !)
I think he said I'm getting 2 x 120Ah AGM's and 40A Redarc BCDC and a couple of oulets and a voltmeter.
The BCDC will be mounted on the side wall of the van between the sliding door and rear and behind the vehicle shelving unit, with a run to the battery of about 300/500mm.
He recons the panel on its own should exceed the fridge consumption, but i can squeeze another two panels onto the roof if I wanted...
Nice.
Those eliptical bars would be a bit quieter Id guess, and I see what youve done with the roll over, nice job, is it your design or factory option ?
The HiAce bars are essentially square, I took the end caps out of the bars on my old van (09 model) and that whistled too, until I hurriedly put them back in.
I lowered my panels 50mm between the crossbars. They don't get any bugs on them... or sun!
No problems with bats either ?
Looks a neat set out.
-- Edited by Northernblue on Tuesday 24th of August 2021 10:35:11 PM
I had a roof platform but chucked it out & replaced it with 2 additional crossbars, so 4 in total, with a net weight saving of 16kg.
Like you I have bought quality solar panels. It's not worth buying the cheap rubbish with utterly deceitful figures that even a pork barrel would fail to deliver!
I went to an aluminium fabricator & got them to bend up two 10 x 50mm flat bar sections to fit between the crossbars. It's not that expensive to get something made specifically to your requirements.