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Installing a DC-AC inverter in a Cobalt

4.2K views 4 replies 5 participants last post by  rahenmaei  
#1 ·
So I have a 1200 watt (continuous) inverter mounted under the driver's seat in my Forester. I've run 4 gauge cable from the battery (a dual purpose marine battery, for slightly better engine-off runtime). Used a 36'' cable for this and the inverter is grounded to one of the seat mounting bolts with like an 18'' 4 gauge cable. Have a 100 amp fuse under the hood (where the battery is) for the unit. I used to have 80 amp fuses but they would blow under max load. I've run it at max load for 15 minutes straight (10 amp air compressor) and did not feel any heat buildup in the cables. I've also checked the vehicle's ground cable to the battery and the alternator's positive cable and didn't feel any heat. I've run the inverter at half to 3/4 load for hours without problems (5k BTU, 5 amp window a/c unit, 200 watt flood light, and a 6 amp sawzall on and off). The vehicle's cables seem to be 6 gauge. They could be upgraded to 4 but again I haven't felt any heat buildup so I don't quite see the need.

I want to install one in my mom's '07 2.2L Cobalt of similar capacity. I figured i could mount it in the trunk and connecting it to power would be easy since the battery is in the trunk.

I'm concerned about the length of the cabling from the alternator to the battery, however. I haven't looked at it yet. Anyone know of its gauge? I have a feeling it's too small for its length to sustain the prolonged electrical load unless I run like 2 gauge cable.

Or should I just hook it up and see how it goes? Due to the Cobalt's sealed battery it would be difficult to upgrade it unless I got a yellow top Optima, and they don't give those away. Thanks guys
 
#2 ·
First check alternator if it is designed for your desired capacity(standard capacity for cobalt is 68 Ah) other ways it can't charge battery sufficient .... and you must do it by auxiliary unit or put more powerful alternator and increase fuel consumption or not log time kill it .... Put such conversion in car is energy inefficient way because most your electrical working equipment working current is around 12V and power adapter transfer current in networks for 110/220 to this number DC or AC this to power your appliances ... for most such things exists adapters easy to connect to 12V yes even mobile workstations (there are even available extra sockets to install internal and external) .... Before use any factory lighter socket check car manual for maximum allowed load limit .... the same thing if you use any built in wiring system lines .....
 
#3 ·
first check alternator if it is designed for your desired capacity(standard capacity for cobalt is 68 ah) other ways it can't charge battery sufficient .... And you must do it by auxiliary unit or put more powerful alternator and increase fuel consumption or not log time kill it .... Put such conversion in car is energy inefficient way because most your electrical working equipment working current is around 12v and power adapter transfer current in networks for 110/220 to this number dc or ac this to power your appliances ... For most such things exists adapters easy to connect to 12v yes even mobile workstations (there are even available extra sockets to install internal and external) .... Before use any factory lighter socket check car manual for maximum allowed load limit .... The same thing if you use any built in wiring system lines .....
is it 4:20................ :d
 
#4 ·
Never a good idea to use body ground as return path from the inverter. Inverter mfgrs always recommend running a home run of 4-ga. back to battery negative. Any corrosion on body ground back to battery creates noise and heat. Also, the best inverter setup has two batteries and a cut-off switch. Second battery is usually a valved regulated sealed lead acid (gel cell). Yeah, they're expensive. That really reduces shock to the alternator. Run the positive inside plastic conduit. Blue plastic "smurf" tube (from a home center) protects the positive cable from ever contacting metal.