03-14-15, 10:10 AM | #141 |
Lex Parsimoniae
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That's the way I understand it.
I was just looking at the truth table for the IC, but didn't want to confuse us.. What you want to shoot for in your voltage divider design, is never allow the input on pin 2, to go so high that it cooks the chip.. Even when PV volts are at max.. I think that's what caused my chip to melt into it's socket.. LOL! Otherwise I would have just plugged in another chip.. The voltage of my 800w array can get quite high..
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03-14-15, 12:13 PM | #142 |
Lurking Renovator
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Why don't you use a zener diode to protect pin 2 from over voltages?
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03-14-15, 12:59 PM | #143 |
Lex Parsimoniae
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I actually didn't think of that until today.. It wasn't in the original design.
I was thinking an 8 or 10 volt zener might work, but I didn't have any.. And, I'm not sure if it's really needed, if you are careful with your PV voltage and current flow in the voltage divider. You would need to make sure that over-voltage current levels were not so high as to exceed the wattage rating of the zener. A 1 watt zener should be okay if you didn't use real low resistances in your voltage divider.
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