Front A/C while driving using SOLAR + ALTERNATOR

[twinboat]

Originally Posted by redbaron73

Wow, that makes sense. They are controlling the motor speed by adjusting the frequency of the 120 , ramping it up to 60hz....that is genius.

Ok, now I am sold, and will be buying a set of these.

You will put that on your Air conditioners to start on low power, but at a Campground with low power, your surge guard won't let them start, because its bad for them.

Humm ?

[NealC]

The GEN while driving is fine and none of us use the GEN enough and this is a great way to put it under load and exercise it. And it’s the least annoying time to run/exercise it for people inside and out. Use your gens!!

[redbaron73]

Originally Posted by twinboat

You will put that on your Air conditioners to start on low power, but at a Campground with low power, your surge guard won't let them start, because its bad for them.

Humm ?

It's not about starting with low voltage. It's about keeping it under 30 amps and running 2 acs simultaneously.

[Rvlegaleagle]

Does installing a soft start void out the A/C warranty?

[4x4]

I also run the AC while driving but I run my rear AC and the dash AC so the entire coach remains comfortable without having to run the gen. The difference is I'm running a Victron Quattro 5kw which AMSolar has uniquely connected to both legs so I can choose any AC without having to use any separate switch. My only problem is I'm running Lithium batteries which require a higher voltage than the alternator puts out so the solar supplies the main power and the alternator assist but not enough to keep the batteries from losing a small amount (8%) of power while daylight is shining.

[C.Martin]

The Alternator on our Ventana is just one step in amperage below one common for school buses that have roof air. I believe the Solar is making up for this difference.

[jharrell]

Originally Posted by C.Martin

The Alternator on our Ventana is just one step in amperage below one common for school buses that have roof air. I believe the Solar is making up for this difference.

School buses and most passenger buses with roof air still use a compressor driven by the engine with refrigerant lines run up to roof. They also are usually much larger than RV air conditioners due to the heat load from many people on board, sometimes 50,000 or 60,000 BTU's.

I have seen some 48v DC bus airs that run off a secondary 48v alternator, which means 1/4 amperage for the same power.

I would be very surprised if a school bus had a 12vdc roof air system running off the main engine alternator.

Most engine alternators rating are not continuous they are max output for short periods to recharge chassis starting batteries. You really need to look close to try and figure out how much they can handle continuous.

[jharrell]

Originally Posted by NealC

The GEN while driving is fine and none of us use the GEN enough and this is a great way to put it under load and exercise it. And it’s the least annoying time to run/exercise it for people inside and out. Use your gens!!

Yep generator is designed for the continuous load and may be more efficient than the alternator->inverter setup especially if you you have a diesel inverter generator like an Onan QD6000 or 8000.

I prefer keeping the load off the alternator as its more critical than the generator.

[C.Martin]

I WOULD NOT RECOMMEND trying this with just any coach.

We have Eight GC-2 house batteries...928aH

1,440 - 1,800 watts of solar

MS2812 Inverter

225 amp bi-directional relay

AVI160P2003 240A Alternator.

MicroAir Easy Start installed on each rooftop AirConditioner.

This also adds an unintended load to the Inverter...so, we have to curtail the use of intended loads such as the convection/microwave while the a/c is running.

This isn’t an endeavor I would recommend across the board. It requires a complement of components to safely achieve...(current belief...still testing)

I intend to get a Bluetooth clamp meter to do some data collection as to just how much the Alternator is contributing...and have inquired as to the duty cycle limitations on our alternator. We’ll see. This is a work in progress...but we have successfully driven a number of trips with the front A/C running off the Inverter. Eventually...I might look into the feasibility of changing to the BLP4009 280A Alternator, if the duty cycle requirements demand it.

The a/c unit requires about 160A and the residential fridge adds another 10A... I am speculating...but the alternator is probably only contributing 100A...solar 70A. Until I record readings from the Bi-directional relay while driving...I only have the Solar readings to use for my estimates.

So, don’t try this at home unless you do your own due diligence.

[jcussen]

I have tried running 1 ac with micro-air for short periods in my driveway.
Had alternator directly connected to battery bank at high idle. Have bluetooth solar controllers, and battery monitor so can ballpark what is being produced by alternator. Appears in good sun, panels where producing about 85 amps and alternator about 75. SOC was staying about 80%. Did not run very long, because used ir gun on wiring and found the new disconnect on the positive battery lead was getting pretty warm. Disconnect is 250 amps and wire terminals are tight [3.0 cable], so suspect some corrosion inside wire terminal.

[96 Wideglide]

Originally Posted by redbaron73

Why pay $300 for a capacitor? Even the dometic version is only $45.00. I put the hard start kit on all my units to run 3 units on 30amp service. Works wonders.

I've melted the plug on a 30amp extension cable, running 2 units, and your running 3 !

[C.Martin]

The AVI160P2003 rated for 240A is cold. Hot conditions they told me to expect around 180A. 100% duty cycle...all day long. It will wear the unit out faster than if left to only charge the starting battery, headlights, and radio...

I believe these alternators sell for around $600-$700...

My Onan with 110.7 hours on it is in the shop. If they have to replace the control board...it is only available on the QD8000 complete with the Inverter... This goes for over $1700... Not a fan of generators right now...

[jcussen]

Originally Posted by C.Martin

The AVI160P2003 rated for 240A is cold. Hot conditions they told me to expect around 180A. 100% duty cycle...all day long. It will wear the unit out faster than if left to only charge the starting battery, headlights, and radio...

I believe these alternators sell for around $600-$700...

My Onan with 110.7 hours on it is in the shop. If they have to replace the control board...it is only available on the QD8000 complete with the Inverter... This goes for over $1700... Not a fan of generators right now...

Looks like a duvac type with a sense wire. Would like the same amperage, but cannot find one that uses a j180 mount. Looks like yours mounts on some sort of adjustable plate? Does it use a single belt?

[C.Martin]

Originally Posted by jcussen

Looks like a duvac type with a sense wire. Would like the same amperage, but cannot find one that uses a j180 mount. Looks like yours mounts on some sort of adjustable plate? Does it use a single belt?

It’s a Leece Neville...

J180 is part no AVI160J2004, if that helps....

https://www.urqualitysolutions.com/N...04-A160204.htm

If you up the amperage...you may need heavier gauge wire and double check amp rating on Bi-directional relay. Don’t want to cook anything. I was thinking about the 280A model...but it’s overkill for our needs.

The problem you might have is with the Lithium voltages. We have a gentleman running solar + alt. He is using the Li-BIM225. It works by time management...so, it’s not keeping the Alternator tied long enough to fully help with the A/C. Bottom line...depleting the SOC of the Lithium’s while driving because the BIM ties for something like five minutes and drops out for 20 minutes (if I remember correctly).

If you have a work around...we’re interested in learning about it.


Ours is the PAD mount. It’s driven by a single accessory drive belt.