photovoltaic panel load problem

Thread Starter

mah

Joined Mar 15, 2010
393
i have photovoltaic panel max 150 watt , i want to put a potentiometer around 20 ohm to be its load . could you propose a solution .
 

wayneh

Joined Sep 9, 2010
17,496
Get out your credit card. They're not cheap.

There are better ways to make a dummy load. What are you trying to do?
 

Thread Starter

mah

Joined Mar 15, 2010
393
Get out your credit card. They're not cheap.

There are better ways to make a dummy load. What are you trying to do?
i want to measure current and volt at maximum power by changing the load resistance using potentiometer.
 

Thread Starter

mah

Joined Mar 15, 2010
393
you want to dissipate 150W. your pot is rated 1W. you will need a pot with 15,000% higher power rating than the one you have.
so what to do ? isn't there resistors with high power ratings , i will also need another one when connecting dc-dc converter.
 

#12

Joined Nov 30, 2010
18,224
I'm getting similar answers at Mouser. $180
Headlights are a lot cheaper, especially at automotive dismantling and recycling emporiums.
 

MikeML

Joined Oct 2, 2009
5,444
Get a bunch of 10W to 50W wire-wound power resistors. Fill a plastic bucket with water. Immerse the resistors in the water. As long as the resistors are submerged in water, they can dissipate about 10X to 20X their rated power. Even if the water boils the resistors will be no hotter than ~100deg C....

Automotive engine oil in the bucket can also be used. Dont burn yourself with the hot oil...

When I started, we used to mount metal-jacket 6L6s upside down in water or oil and get 100W of RF on 40meters out of them.
 
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