If the panels pull 3.5 Amps each and there are 5 in parallel, then you are indeed pulling 17.5 Amps. But this is at 12 Volts. This means the whole thing is only drawing 210 Watts..
Doing it this way means you'll need to step down the 120 Volts from the outlet to 12 VDC. You'd only be pulling about 2 amps from the wall.
Thoughts on this ebay panel,
I'm planning on running them at 11.5v which results in ~2A depending on each individual panel. Migrow did a YT video on this and confirmed at that amperage they shouldn't need a heatsink. I'm going to hang them by using thermal glue to attach them to 2 sections of aluminium angle which should give any slight cooling they may need.
I won't be running them on AC, the power supply will convert 240v AC to 12V DC and can supply up to 12.5A. 150w AC should only be a couple of amps at the wall.
I won't be running them on AC, the power supply will convert 240v AC to 12V DC and can supply up to 12.5A. 150w AC should only be a couple of amps at the wall.
One part of the plan I am not sold on is the boost converter, it got really hot very fast and I am not sure I want to deal heat management for that. So I am contemplating either a spaghetti monster 12v all parallel build or a slightly less spaghetti 24 v build with a mix of parallel and serial.
And since this will run a bit more current through than expected I suspect active cooling might be needed , Next test will be one light properly attached to a sink and run for a couple of hours.
And since this will run a bit more current through than expected I suspect active cooling might be needed , Next test will be one light properly attached to a sink and run for a couple of hours.
I don't know what country you're in but you might want to take a look at these power supplies
[US]https://www.ebay.com/itm/AC-110V-220V-T ... :rk:1:pf:0
[UK]https://www.ebay.co.uk/itm/DC-12V-LED-D ... :rk:2:pf:0
They are available throughout the world so you wont have an issue getting one that suits. They come in numerous voltages 12v 24v 36v depending on what configuration you want to run.
The good thing about them is that they have an adjustable voltage from 9v~ to 14v~ You can drop the voltage on them to 11-11.5v and because of the relationship between voltage and amperage the panels will draw less current and in turn not require heatsinking.
bigclivedotcom lists his panel as performing as follows:
10V 7mA 70mW
10.5V 170mA 1.8W
11V 790mA 8.7W
11.5V 1.72A 19.8W
12V 2.85A 34W
12.5V 4.2A 52W
12.8V 5.2A 66W Current Limit of bench supply.
So you could run 2 of them in paralel at 11.5v at 20w~ each and they won't need heatsinking. Even though the supply is capable of providing 10 amps, it won't supply that much, just the sum of amperage per panel which at those voltages would be about 2+2=4 amp.
Just be sure however many you go with to use a sufficient guage of awg to cover the amperage. I'm planning on being able to use all 150w so that's 12.5 amps and I'd use 14AWG which can safely carry 20 amps.
Here is a video demonstrating the 10A version of the power supply
Overcurrent and short-circuit protection make it plenty safe provided you put it in a suitable vented plastic enclosure.
[US]https://www.ebay.com/itm/AC-110V-220V-T ... :rk:1:pf:0
[UK]https://www.ebay.co.uk/itm/DC-12V-LED-D ... :rk:2:pf:0
They are available throughout the world so you wont have an issue getting one that suits. They come in numerous voltages 12v 24v 36v depending on what configuration you want to run.
The good thing about them is that they have an adjustable voltage from 9v~ to 14v~ You can drop the voltage on them to 11-11.5v and because of the relationship between voltage and amperage the panels will draw less current and in turn not require heatsinking.
bigclivedotcom lists his panel as performing as follows:
10V 7mA 70mW
10.5V 170mA 1.8W
11V 790mA 8.7W
11.5V 1.72A 19.8W
12V 2.85A 34W
12.5V 4.2A 52W
12.8V 5.2A 66W Current Limit of bench supply.
So you could run 2 of them in paralel at 11.5v at 20w~ each and they won't need heatsinking. Even though the supply is capable of providing 10 amps, it won't supply that much, just the sum of amperage per panel which at those voltages would be about 2+2=4 amp.
Just be sure however many you go with to use a sufficient guage of awg to cover the amperage. I'm planning on being able to use all 150w so that's 12.5 amps and I'd use 14AWG which can safely carry 20 amps.
Here is a video demonstrating the 10A version of the power supply
Overcurrent and short-circuit protection make it plenty safe provided you put it in a suitable vented plastic enclosure.
So the project has progress. I sourced out a 12v 250w CV power supply it turns out a local 3d printer shop had some for a competitive price. When I found out there was adjustment of the output voltage that pretty much pushed me in that direction.
I then properly mounted up the paneld to my heat sink and ran a couple of tests.
Test 1 adjust the voltage to my target 36w and let it run. As it warmed up the draw increased so what I did is dial back on the voltage until I could maintain 36w. Now I did not have any way to actually measure the working temperature, but I had my 3d printer going near buy and the bed temp was set to 60c and the top of the heat sink was getting close though the bottom and the light seemed cooler.
Test 2 I added the cheesiest 2$ CPU fan to provide active cooling. After letting the light cool, I turned it back on the initial setting only ran at 25w , but the setting stayed steady and hour later the power usage was still 25w. So I turned it up to 36w and let it run, and it still stayed steady. And the heat sink was barely warm when compared to the other heat sinks at ambient (17c).
So I guess I will be actively cooling the light.
Next step hang it over some plants and see what happens
So here is a question was the 36w passive setting producing the same amount of light as the 36w actively cooled setup .
I would also assume that for safety having a 4a fuse would be minimum for safety but a current limiting resistor would be better to protect from thermal runaway.
I then properly mounted up the paneld to my heat sink and ran a couple of tests.
Test 1 adjust the voltage to my target 36w and let it run. As it warmed up the draw increased so what I did is dial back on the voltage until I could maintain 36w. Now I did not have any way to actually measure the working temperature, but I had my 3d printer going near buy and the bed temp was set to 60c and the top of the heat sink was getting close though the bottom and the light seemed cooler.
Test 2 I added the cheesiest 2$ CPU fan to provide active cooling. After letting the light cool, I turned it back on the initial setting only ran at 25w , but the setting stayed steady and hour later the power usage was still 25w. So I turned it up to 36w and let it run, and it still stayed steady. And the heat sink was barely warm when compared to the other heat sinks at ambient (17c).
So I guess I will be actively cooling the light.
Next step hang it over some plants and see what happens
So here is a question was the 36w passive setting producing the same amount of light as the 36w actively cooled setup .
I would also assume that for safety having a 4a fuse would be minimum for safety but a current limiting resistor would be better to protect from thermal runaway.