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Old 12-20-2009, 02:34 PM   #47 (permalink)
Xringer
Old Retired R&D Dude
 
Join Date: May 2008
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Quote:
Originally Posted by smokeyj View Post
The FET will most likely be controlled to act not as a switch ie ON or OFF but as a variable resistor.

Its job is to absorb the excess power put out by the panel. So if the battery for its charging needs requires only 5W of power and the panel is putting out 14W the extra W will be absorbed by this FET and dissipated as heat.

This 60V panel is really intended to charge a 48V battery. In this case the panel and the load are well matched. This panel will only be able to put about 1.2A into a 12V battery which is about 14W of charge power.

If you read the panel spec it claims an short circuit current of 1.2A. No way no how will it put out 5A.
After looking it up, I see the light.

Pretty simple, and pretty wasteful IMHO.
Now, I'm starting to think the more expensive HV charger is the only one for these 60V panels.
I like all the neat features of the high dollar unit anyways.
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Rich

Current ride: 2014 RAV4 LE AWD (24 MPG)

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