Thread: Getting high current 12v from 24v systems

Found them to be better in theory than practice.. Have a look at a company called AMELEC, they are a WA company and make some really good gear here. 24 to 12volt chargers and converters.

Originally Posted by Blknight.aus

cept they dont work long term (on high current loads)... they just stop the short term effects like boiling off the charged battery withing the amps range of the charge balancer.

you could do the same thing with a string of lights that match the power demand of the stereo wired across the battery thats on the +'ve side of the bridging cable.

It did occur to me to use one amp across the 'top' battery and the other across the bottom one.. LEFT channel on 'top' and RIGHT channels on 'bottom' (balanced load on both batteries) - Which is how I'd do it IF it was my bus, and the budget was limited, AND I felt like bothering with floating earths and isolating the inputs, balanced lines etc etc blah blah....

Using a 2kW / 24v inverter/charger driving his 240vac amplifiers is just too... simple. Only $1500 or so at Jaycar, less for 'Trade'. - And keep the engine running !!!

The consensus seems to favour the 'Hi-Tech' approach for predictable and light loads, (Balancers or 24 to 12 volt supplies) and the belts and braces - biggg 12 v battery banks fed with huge on-board charger(s), or total 12 v battery/alternator approach. for the insanely hungry user....

By now I've totally confused the poor bloke !

Originally Posted by superquag

It did occur to me to use one amp across the 'top' battery and the other across the bottom one.. LEFT channel on 'top' and RIGHT channels on 'bottom' (balanced load on both batteries) - Which is how I'd do it IF it was my bus, and the budget was limited, AND I felt like bothering with floating earths and isolating the inputs, balanced lines etc etc blah blah....

Using a 2kW / 24v inverter/charger driving his 240vac amplifiers is just too... simple. Only $1500 or so at Jaycar, less for 'Trade'. - And keep the engine running !!!

The consensus seems to favour the 'Hi-Tech' approach for predictable and light loads, (Balancers or 24 to 12 volt supplies) and the belts and braces - biggg 12 v battery banks fed with huge on-board charger(s), or total 12 v battery/alternator approach. for the insanely hungry user....

By now I've totally confused the poor bloke !

try your first approach and something will go foom.... usually an amp. (dont ask)

"...try your first approach and something will go foom.... usually an amp. (dont ask)


- Why not ?

I like ' foom ' ....

I made the mistake of helping someone else do something similar on a truck...

he'd run a pair of switched and fused power feeds in for me, I metered it and got 12v on the 2 wires, brilliant... hooked up the amps to the feeds hed provided aaaand set fire to one of the amps.

got out to check what was going on...

one amp hooked up and went nicely so I hooked up the other to the second power feed but what I thought was the -ve was actually +12v relative to the vehicle earth and what I thought was +12V was +24v.. hooked up the thing, flipped the switch and it worked for about 20 seconds then the smoke started (and Im talking the kind of smoke that puts fozzy on a cold morning to shame)

on the subject of fusing... a 200A fuse will conduct enough grunt to melt the guts out of an amp.. an unfused cable rated for 200a if hooked from the bridge cable of a 24v system will quite happily reduce the ally casing of an amp to slag if you happen to inadvertently drill the mounting screw through the MDF board into the steel frame.