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50 crown 08-10-2018 08:27 PM

belt driven generator questions
Hello fello skoolie's,
I am in the process of finishing up my electrical and the following ideas and could use some feed back.

I'm planning installing a 220v mini split and using a 220 inverter and Generator when no shore power is available. now I noticed a large belt driven possibly hydraulic pump bolted ( not being use) on the front of my 220 cummins and thought wow what about just installing a 220 generator head to that and not purchase a 8-10k diesel genset takes up a lot of room underneath the coach and vibrate my bedroom.
I see there are some good ones out there that have computer controlled regulators to I think keep the voltage steady.
any thoughts or comments. I plan to have 1k watts of solar up top and viltron inverter to run everything.
thanks in advance

Iceni John 08-10-2018 09:59 PM

You say this possible hydraulic pump is not being used? If it's for the power steering, do you now have good ol' Armstrong steering (i.e., no power assistance at all)? A 1950 Crown would not have any other need for hydraulics, so what else could it be?

1kW of solar panels are not enough to power a large minisplit A/C by themselves. Are you thinking of using a new alternator to charge only the house batteries, or both the house and start batteries, or what? Just bear in mind that alternators designed for SLI batteries don't do a good job of charging deep-cycle batteries such as would be used for a house system - they do not have a programmable 3-stage charging regimen like a good charge controller or 120VAC charger has, so the deep-cycle batteries will eventually end up deficit-charged and die a premature death.

Tell us more about how you plan in integrating a new engine-driven alternator with the PV system - we're very curious!


50 crown 08-10-2018 11:31 PM

1 Attachment(s)
o wow never crossed my mind thats its possible the power steering pump !!! ya this crown is a tuff steerer and I was looking for a power asst or something. the bus had a hall Scott originally and so the new motor must have came with this pump. well that possibly changes that idea haha.
I can't figure out how to post a pic yet or I would share the photo.

I planned on a inverter charger to charge the battery, and adding a 220v generator on the house engine connected to the transfer with. so while the the bus is running it will act as penny/shore power and the system wont switch to batteries. I'm looking into 400 ah victron system for charge controller, inverter/charger and the hole shebang.

I see your a local crown owner as well. nice to meet you.Attachment 24876

Ronnie 08-11-2018 05:43 AM

that does look like it is for power steering. I see it is looped back to itself. Maybe your bus does not have power steering so when they swapped engines they just left the pump disconnected. Check the steering for a hydraulic cylinder, or any connections for hydraulics.

JDOnTheGo 08-11-2018 08:44 AM

What kind of generator head? How are you going to control RPM and/or generator output?

50 crown 08-11-2018 09:25 AM

this is what I was looking at. basically a AC alternator ( I already have a engine capable of running this lol ) what do you think ?

Specifications: Ratings
MODEL Volts Amps
Peak Watts
Peak Watts
Continuous RPM Weight
PM-110 120 29 3500 2500 3600 27 lbs.
*Blue Max 120 37 4500 3000 3600 32 lbs.
*Blue Max 50 hz. 120 30 3600 2400 3000 32 lbs.
*PM-220 220 15 3500 2500 3600 27 lbs.
*PM-220 50 hz. 220 13 3000 2000 3000 27 lbs.
• These models must be ordered with a voltage regulator

Patent #6528973

The Optional Power Mite® Voltage Regulator provides constant voltage at varying engine speeds. The innovate design of the Power Mite® Voltage regulator is unique. There are no relays, transformers or moving parts to wear which make this unit extremely reliable under the most severe conditions.


JDOnTheGo 08-11-2018 09:37 AM

That is VERY interesting. What does one of those cost (plus the regulator)?

50 crown 08-11-2018 09:51 AM


Originally Posted by JDOnTheGo (Post 285620)
That is VERY interesting. What does one of those cost (plus the regulator)?

I don't have a exact price yet, however off my research it looks to under 1k

I found this company that states constant voltage and all size wattages. just seam like a lot less room and they talk about only using like 6-8 hp to run.

Ronnie 08-11-2018 11:21 AM

I have one of those....on a cat 3406. Do not use it anymore. It only gives proper voltage at full engine speed. If you can over speed it with a larger engine pulley maybe it would regulate. however it will not boost voltage if the speed is to low. I just can not see running a large engine at full speed for a little electricity. Would rather not put the wear on the prime mover.

Ronnie 08-11-2018 12:09 PM

Just to clarify, mine is the Fabco unit. The other link you show to meps looks like a true alternator. Fabco is a generator.

So for the record, my Fabco has been reliable; 20 years it has been on there. Had been used about 40 hours a week for some time. Until we got a real generator. Every time we shifted gears, the voltage changed until full speed was resumed. That is hard on electronics like a stereo system. Fried a few of them. Drops to about 50 volts at idle. It is used sometimes when we can set the throttle and let it run.

Now if you have a spare engine laying around, 10 hp or so, then belt drive it off that. Then you would set it up for constant speed and it will do great.

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