An electrical engineer has confirmed that my voltage drop issues (lights flickering, fridge compressor won’t start), stems from a mistake made by the marine electrican who installed a Smart Battery Protect. The out goes to a 400 amp fuse, which the inverter switch is connected to. See photo. The inv…

A schematic would be helpful. Is the inverter just an inverter or can it charge the battery using shore power as well? How powerful is it, have you checked currents while the things are running? Looks like a BP-220, so a 400A fuse, and i suppose up to 400A of load, would be a bit much for it.

The inverter should not be connected to/through the battery protect at all it is unidirectional.

@lbayne Hello lisa, I dont know of your setup, but if you supect the SBP unit is faulty, just test the voltage across the two studs you can see with a multimeter. If you dont have one, you can buy a small one for quite a cheap price. Just set it to DC Voltage and touch the probes onto the two stu…

The inverter is 3000 watts and does not charge the battery. BP 200 Here’s the schematic. [IMG_8422] [IMG_8421] Current dropped when a light was turned on, but I don’t remember how much.

If I did it correctly, both posts showed a little over 4.6 v. The Victron app reads battery status 13.37, load output state active, preset is 0, mode A, operation-normal. On the unit is 8. The marine electrician who originally installed the BP last fall, just installed a new one a couple of months …

@lbayne the SBP is open circuit if has 4.6 volts across it. It has either been instructed to open by whatever is controlling it or it has failed. If you need to immediately get your fridge to work simply remove the SBP from the circuit by moving both cables onto one stud. That way the SBP prot…

Whats the make and model of the inverter? It looks like it can switch over from inverting to shore power, the unit then also being able to charge the battery is not too far fetched. The BP would definitely not like that

This seems like a viable explanation. This is the second smart battery protect unit that the electrician has installed in a year. It sounds like he could be installing a third one this week. Thank you so much for helping me to understand what’s going on.

The inverter is Renogy 3000 W. It Doesn’t charge batteries. The switch controlling the inverter has been off as seen in the previous photo there’s still lights flickering and Fridg won’t run, which causes me to believe the battery protector is damaged. (?) Thank you so much for the feedback.

I’m not one of the forum experts, so I hope I’m not speaking out of turn; but I thought that it wasn’t permissable to have an inverter on the output side of a BatteryProtect (because the inverter capacitor draws cause the BatteryProtects to fail). Could this be the problem? From the BatteryProtect…

Smart Battery Protect voltage drop

DIY

nesswill (Dave) 9 September 2024 07:19 13

This

3.2. Warning when connecting inverters and inverters/chargers

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Smart Battery Protect voltage drop

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