Some afterthoughts and observations

This is part of the Inverter Power project.

How is it working? I’ll let you know when we use it……

Someone brought up weight. The 6 batteries are light (28.7 pounds), the inverter charger is about 50 pounds, then there’s probably another 40 or so pounds of cable and wood. Call it 270 pounds. I didn’t weigh them but the seats that came out were not light. At least 220 or so pounds. So, the difference is negligible.

Even though I have exercised caution in design, the selection of materials and installation there is a LOT of energy in those plastic boxes, and it’s traveling through extensive cabling (relatively speaking), sometimes at fairly high volume. The highest risk, in my opinion, is the failure of a BMS, and there are SIX of them wrangling their respective cells. So if it runs away, it’s gonna be ugly. I have no illusion of putting out a fire, but I figured I put one of these within reach to buy me some time if it happens…..

There’s another matter. The “Peak Load” of an inverter, for short periods, is boosted by capacitors. Big ones. On large inverters they are so big in fact that the inrush of current to charge said capacitors when connecting the inverter to the batteries can be enough to cause spark or even “welding” between terminals. Same when using a battery cutoff switch. In addition it can freak out the BMS’s on the batteries. All bad. Will Prowse shows how you use a resistor (30A 25Ω in his case) to pre-charge the capacitors at a slower rate. There was some discussion as to whether my system is large enough to require this…. but just for fun I put in this momentary switch and resistor……


Back to Inverter Power.