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Pre Charge Circuit for solar controllers and Inverters

DIDDLYV

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Mar 1, 2021
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I am considering wiring in a pre-charge circuit for my solar controllers using a 100 watt 30 Ohm resister a switch and probably 10 guage wire to essentially bypass the main breakers to the SCCs and a separate bypass with another resistor for the inverter. The goal is to pre-charge capacitors prior to connecting the main current to these devices to reduce arcing. Is this a good Idea, a bad Idea or just over kill. In theory given electricity takes the path of least resistance in practice I probably would not need to turn off this circuit when I switch the main power on, but will always switch it off in practice
 
My brain is getting foggy as time goes on. I need help with a pre-charge circuit. The part I need help with is connecting a combo V & I meter in the circuit. I would like to monitor the voltage & current during pre-charge. I'm having trouble wiring the combo meter into the pre-charge circuit. I only want the meter active when the switch is pressed. I know I could use DVM across the breaker terminals, but what fun is that. Having a panel mount switch & meter seems fancier. Attached drawings are simplified.
 

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My brain is getting foggy as time goes on. I need help with a pre-charge circuit. The part I need help with is connecting a combo V & I meter in the circuit. I would like to monitor the voltage & current during pre-charge. I'm having trouble wiring the combo meter into the pre-charge circuit. I only want the meter active when the switch is pressed. I know I could use DVM across the breaker terminals, but what fun is that. Having a panel mount switch & meter seems fancier. Attached drawings are simplified.
I have to ask why you think the meter is necessary on a pre-charge circuit? You only pre-charge for about a second or two.

If you really want to know, you would get more data using a 2 channel DSO with one channel on voltage and the other with an amp clamp. But all you will see is a spike to max battery voltage and corresponding spike in amps.
 
I have to ask why you think the meter is necessary on a pre-charge circuit? You only pre-charge for about a second or two.

If you really want to know, you would get more data using a 2 channel DSO with one channel on voltage and the other with an amp clamp. But all you will see is a spike to max battery voltage and corresponding spike in amps.
You are right. I don't really need to monitor the pre-charge. It was just a hobbyist idea I got carried away with. I will probably only install the switch, resistor, and a 1A inline fuse. I was wondering if I wired it correctly.
 
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