| Author | Message | ||
| Roger Baughman (Roger)
Registered Member Username: Roger Post Number: 115 Registered: 11-2006 Posted From: 71.140.123.90  Rating: N/A |
I have a 4024 pur sinewave inverter on order. I orginally planed to use the MCI engine 24 volt alternater to power my two roof 13,500 btu, 20 amp air condtioners, This is what George recomended for this purpose. Now my question is will this set up also have enough power to operate a small window type 5,500 btu, 7.6 amp air unit. I have enough room in the conpartment under the drivers seat to put the unit and run a 4 inch air supply to the conpartment that houses the two OEQ fans that push air to the windsheild. All ideas welcome. | ||
| David Lower (Dave_l)
Registered Member Username: Dave_l Post Number: 171 Registered: 11-2007 Posted From: 67.58.201.132  Rating: N/A |
I was curious Roger where will the small window a/c exaust to. Dave L | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 845 Registered: 10-2006 Posted From: 76.216.70.120 Rating: N/A |
Most good inverters can start at least 200% of the constant load , some even more. The Trace is honestly rated and should take a constant 4000W load , and be able to start the air cond , ONE AT A TIME . Will work your bus alt fairly hard. And not last on batteries very long . FF | ||
| Pete/RTS Daytona (Pete_rtsdaytona)
Registered Member Username: Pete_rtsdaytona Post Number: 560 Registered: 1-2005 Posted From: 97.104.15.224  Rating: N/A |
here's a useful guide--> http://www.hayesequipment.com/honda_generator_wattage_guide.htm so: (2) 15k A/C units = 3000 run watts 7.6amps x 120v = 912 watts total -> 3912 That's without your electric refer ?? too close to the max for me Those draws are average consumption - when it's real real hot out they may draw more the hotter the inverter gets - the less it's outputs runing one rooftop and the small dash air would work fine another idea - put a 12v car alternator on your engine or pto?? and run a cheap Harbor freight Modified Square Wave 2000 watt inverter ($150) for your dash A/C | ||
| Pete/RTS Daytona (Pete_rtsdaytona)
Registered Member Username: Pete_rtsdaytona Post Number: 561 Registered: 1-2005 Posted From: 97.104.15.224 Rating: N/A |
one more point your 50DN Detroit Diesel is rated at 150 amps at 24-28 volts ON IDLE - that just UNDER 4000 watts at idle and about 6000 watts at highway speed - remember some power is also needed by the battery recharge regulator system BUT Inverters are NOT 100% efficient - so it will take about 5-10% more input vs output power which means when the bus is idling - the batteries will have to make up the difference | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 1528 Registered: 10-2003 Posted From: 71.58.110.9  Rating: N/A |
Some of the city bus versions are rated at 450 amps. Don't know how they would hold up for otr use. | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 1640 Registered: 12-2000 Posted From: 76.71.103.234  Rating: N/A |
Make sure you have lots of cooling available for the inverter. Closed up in the bay is NOT sufficient, there will be a lot of heat being thrown powering the two roof airs. Rig up some duct work for some intake and exhaust. I know some who also have added a squirrel cage fan, supplementing the inverters own internal fans to ensure hurricane winds through the inverter. Heat kills electrics, and those inverters are not cheap! Yes, a newer high powered transit alternator would be a GREAT choice for this application. Costly, but an excellent choice. I did the math back whenever, the two roof airs run off the inverter draws pretty much the same electric power that the stock HVAC system, with the two big fans, did, so from the alternator's perspective, it's just another day. Same as a stock HVAC, the fast idle switch comes in handy for the same reason. Of note also, the new MCI J models have ducted the Bosch air cooled alternators to the outside to get them fresh cool air. The vent in the curb side engine/toilet access door seals up against the piping that "Y's" and seals against the back side of both alternators. I'll be adding that little project to the list for my old 4 belt driven, air cooled unit. happy coaching! buswarrior | ||
| Jerry Liebler (Jerry_liebler)
Registered Member Username: Jerry_liebler Post Number: 342 Registered: 3-2005 Posted From: 98.19.232.150 Rating: N/A |
Roger, I fear you're headed for disappointment. if you have any other loads powered by the inverter, like a refrigerator. Rooftops are simply not very energy efficient and a 13500 BTU unit will often draw 14 amps or so and more as the outside temperature rises. Your inverter will shut down if the load it sees is above 33 amps for a sustained time. The two rooftops alone may draw this on a hot day. Add 2 amps for a refrigerator and the trip point will occur at a lower outside temperature. However one rooftop and your small AC unit should work well. Regards Jerry 4107 1120 |