home made inverter generator, welder, battery bank charger

oil pan 4 · 07-11-16, 06:34 PM

home made inverter generator, welder, battery bank charger
Next build...
For my next build I am going to build a welding generator with 120v power.
I am using a 25 horse power 1-7/16 inch keyed shaft, air cooled V-twin robin Subaru engine with built in 20 or 30 amp charging coil. The 25hp engine Problem is I cant seem to get an engine with a heavy duty 30 amp charger and heavy duty cyclone air cleaner. I can always generate more 12v power so I will take the HD air cleaner over not having an HD charger. I might just add a third alternator just for battery charging and to help power the 2000w inverter.

As you can guess the 25hp engine, 2,000 watt inverter and low charging amps this rig is mostly a welding machine. The 25hp is a little over powered for what I need but this will help over come the thin air and have plenty of power run at part throttle to save fuel and engine life.
The plan is to use the 25hp engine to drive two specially modified GM type AD244 alternators.
The third alternator, if I used it then it will just be an unmodified 10SI or 12SI alt. The third alternator just produces 12v power for the inverter, fans, starting battery. The power alternators can also do 12 volts.

To save fuel in cold weather I am using one of these:
Thermostatic warm air intake - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com
Its a thermostatic air intake.
Other fuel saving measures:
The engine is going to be built in an enclosure to get the engine up to proper operating temperature and vented with electric fans. This is what I don't want:

Another fuel saving trick will be to unbelt alternators when they are not needed.
Over drive alternators by 1 to 2.5 so they make good power at 2500 engine RPMs and insane power at 3,600.
I can get 120v power with the engine off or at idle. Only the most expensive welding machines provide 120v power at idle, non make 120v power while off.

A little bit about how it works. The 2 power alternators can independently provide constant voltage power for battery charging or starting assist up to 48 volt banks and mig welding or constant current supply up to 150 amps of stick and tig welding.
Constant voltage Each power alternator will provide up to 200 to 250 amps of 12 volt power, at 24 volts around 100 to 200 amps, at 48 volts 50 to 100 charging amps.
Constant current mode provides power for stick and tig welding. The 12 volt charging system will provide exciter field power for the power alternators.

Whats not shown in that schematic: The second alternator, anti CEMF diodes, protection MOVs and stuff that keeps the capacitors from exploding and digital displays from burning out.

As far as where is all this equipment going to go, I think I will put it on a skid.
The 25 gallon fuel tank is out of my old suburban.

07-11-16, 06:34 PM	#1
oil pan 4 Land owner Join Date: Nov 2012 Location: NM Posts: 1,026 Thanks: 12 Thanked 127 Times in 107 Posts	home made inverter generator, welder, battery bank charger home made inverter generator, welder, battery bank charger Next build... For my next build I am going to build a welding generator with 120v power. I am using a 25 horse power 1-7/16 inch keyed shaft, air cooled V-twin robin Subaru engine with built in 20 or 30 amp charging coil. The 25hp engine Problem is I cant seem to get an engine with a heavy duty 30 amp charger and heavy duty cyclone air cleaner. I can always generate more 12v power so I will take the HD air cleaner over not having an HD charger. I might just add a third alternator just for battery charging and to help power the 2000w inverter. As you can guess the 25hp engine, 2,000 watt inverter and low charging amps this rig is mostly a welding machine. The 25hp is a little over powered for what I need but this will help over come the thin air and have plenty of power run at part throttle to save fuel and engine life. The plan is to use the 25hp engine to drive two specially modified GM type AD244 alternators. The third alternator, if I used it then it will just be an unmodified 10SI or 12SI alt. The third alternator just produces 12v power for the inverter, fans, starting battery. The power alternators can also do 12 volts. To save fuel in cold weather I am using one of these: Thermostatic warm air intake - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com Its a thermostatic air intake. Other fuel saving measures: The engine is going to be built in an enclosure to get the engine up to proper operating temperature and vented with electric fans. This is what I don't want: Another fuel saving trick will be to unbelt alternators when they are not needed. Over drive alternators by 1 to 2.5 so they make good power at 2500 engine RPMs and insane power at 3,600. I can get 120v power with the engine off or at idle. Only the most expensive welding machines provide 120v power at idle, non make 120v power while off. A little bit about how it works. The 2 power alternators can independently provide constant voltage power for battery charging or starting assist up to 48 volt banks and mig welding or constant current supply up to 150 amps of stick and tig welding. Constant voltage Each power alternator will provide up to 200 to 250 amps of 12 volt power, at 24 volts around 100 to 200 amps, at 48 volts 50 to 100 charging amps. Constant current mode provides power for stick and tig welding. The 12 volt charging system will provide exciter field power for the power alternators. Whats not shown in that schematic: The second alternator, anti CEMF diodes, protection MOVs and stuff that keeps the capacitors from exploding and digital displays from burning out. As far as where is all this equipment going to go, I think I will put it on a skid. The 25 gallon fuel tank is out of my old suburban. Attached Thumbnails