Lasted edited by Andrew Munsey, updated on June 15, 2016 at 1:22 am.
The baldor is a 15hp 220/440V 40/20A rated motor. Its setup with a binary switchable cap bank for ease of adding/removing capacitance. So far I've only gotten the motor to spin up and run idly on 120VAC.
The shots I've attached are showing the inside of the cap bank box, and the motor with meters on it showing 118V at 1.5Amps input to spin the motor at idle... which is around 177watts versus the nominal 8800watts that would other wise be needed to just spin the motor.
"The big 15hp setup, just the motor itself is rated at 8.8kW, and I can power it up and run it on about 110watts with no load off the axle versus the otherwise required 8.8kW just to have it on by conventional EE standards."
Did some better...118VAC @ 600mA w/58uF - dropped another 100 watts at idle by adding 33.5uF
15th jan 2007
http://video.google.com/videoplay?docid=-5606790786763440693 - Rotoverter replica output to 2x 60watt 120V bulbs serial
These are a couple short clips showing the RV PM/RV Alt 1/3HP motors auto-pulsing out thru an SCR with a diode/pot on the gate to adjust the amplitude before the SCR fires. The Clamp AC Ammeter is showing AC amps and at each firing of the SCR you can see that the amp reading varies immensely... There are pulses up to ~29amps AC being measured by the clamp ammeter in one vid and 28.4amps in the other vid.
That said the SCR pulser is no more as I blew the SCR out by creating to many over amped pulses for the little NTE5556 SCR which was only meant to handle 25amps repetitively. To see kind of what type of SCR circuit I used you can look at http://www.allaboutcircuits.com/vol_3/chpt_7/5.html
Shows Serial cap voltage in sync with audible swings
Shows battery voltage in sync with audible swings
these videos are for showing Hectors teachings about how to tune the impedance of the RV alternator (simply put)
"The smaller 1/3hp setup will run on 120V at .1amps with no load on the axle, versus the plate rated 460VAC at .85amps. Thats only ~12watts versus the other higher 391watts of power to be used under conventional wiring methods. "
Its definitely energy savings... amp draw increases as loading on the axle goes up... basicly only draws what it needs to maintain rotation... tho more caps have to be added to accomodate the tuning so that the voltage in the tank doesn't drop below the voltage of the mains. Once it drops below mains voltage the tank will empty and the motor will stall... or at least the behavior I saw with the big 15hp motor.
I wanted to layout the setup I'm working on now with guidance from the group. I've a pair of Baldor 1/3hp 1770rpm 230/460VAC motors that I have nose coupled with a spider coupling. One is wired for RV prime mover layout using High Voltage configuration of wires in 460VAC wiring layout. The other is wired in parallel as the RV Alternator. (wired for 230VAC layout). By the way, Kones diagram outlining the RV wiring schematic is the best pic I've seen that shows how simple it is to RV a motor. Not sure if thats on panacea or peswiki but it should definitely be referenced in both places. As is I have it on the wall in my garage/lab area... haha
Two of these motors are still available at www.surpluscenter.com if someone wants to replicate or can locate two of the same from baldor or used somewhere. Heres the link.
On the Prime Mover I have it using 17.5uF start cap (switched out after reaching 1770rpm), in parallel with 4uF as the run cap (all caps are run caps on this setup) with an additional 3 uF capable of being switched in or out in as little as .25uF increments. 4uF - 7uF as the run cap adjusts the amount of voltage that is created in the circulating tank on the delta wired RV Alternator side.
To sum up RV Prime Mover uses:
17.5uF Start cap (switchable in/out from the circuit.)
4-7uF run cap
Requires 120VAC at .1-.3amps input. (at startup it uses .8-1amps input at same 120V)
The RV Alternator is setup in a delta configuration using 2uF between each phase of the 3 phase windings. In addition to the 3 x 2uF caps in the delta locations, there is an exciter cap that has to be installed between any two phases of the RV Alternator. In this Motor its setup to be a 14uF exciter capacitor. (all these caps are run caps as well). Then there is two diodes, one setup as blocking and one as allowing, from each phase connection forward into a DC electrolitic cap which is at 670uF 450VDC rated.
To sum up RV alternator:
2uF delta cap inteconnecting between each phase
14uF exciter cap between any 2 phases
Diodes I used are 1n5408's, 3 in parallel in each direction at each delta location.
670uF DC electrolytic cap to hold cumulative charge.
This would net me ~158 volts in the DC cap after the RV Alternator kicked in and started generating voltage. At this point I had a simple SCR pulse circuit laid out using an NTE 5556 SCR with a 1n4007 diode and 10k potentiometer on the gate to adjust the firing amplitude. (tho I blew out that SCR as its rated for constant 25amp flow, and I was pushing over 30 amp pulses thru it when I had been rigged to dump ~5800uF at 30volts) At this point I have no output mechanism on the setup. It just fills the cap and I touch the cap polar sides with a 120VAC 100watt light bulb to discharge the power stored.
This is my "learning" setup so I can hopefully garner functional details and apply them to my big setup which is the 15hp baldor connected to my 5kW genhead. I believe I have a better understanding having set these up and tweaked them thus far tho I'm still a good ways from being done with the basic small setup.
Hopefully someone may want to again replicate what I'm replicating of Hectors work and we can all co-mingle the functional aspects and make this a simple (even simpler than it is now) means to an end.
Any questions, feel free to ask. Next up is transformers and tuning the RV Alt side output to a useable power ratio... :)
"I found new values that create a 2amp output off the RV Alternator that swings with a frequency of around 2seconds per full oscillation. Anyways the values work for the 1/3hp motors when they are 1:1 coupled."
RVPM run cap=9uF
RV Alt serial cap=3uF
Ran but with hardly any charging effect to the wet cells. Ed suggested larger serial caps to take advantage of the charge available so I went to larger serial caps.
1st revision: (16-april-2007)
RV PM run cap=11uF
start cap= 17.5uF
RV Alt serial cap=10uF
When I went to the larger serial cap I had to increase the vector cap to almost double to get it to again go into resonance. I also had to add another 2uF on the front end run cap to get the resonance to return. I then just tried adding values to the vector cap to see how I could tune it... and it turned out that shifting the vector cap up to 20.5uF (adding 3uF more) allowed a better flow of power. This was still giving the heavy swings, so I added another 3uF to the vector cap, making it 23.5uF but this worsened the swing and the voltages on the serial caps decreased about 5 volts... so I pulled that 3uF back off.
This was when I wrote that note about needing more uF on the run caps to smooth the swing out. Last night I added another 2uF to the run cap on the RV PM and this smoothed out the swinging such that I was getting a constant serial cap VAC of 92-96VAC. It was also notably charging the batteries where as the 3uF caps were hardly causing any charge. I left it on for about an hour and with it running smoother and tuned the batteries charged from 12.40 to over 13.11volts... (with one battery being known bad due the hydrometer testing.) I then shut it down.
RV PM run cap =12-13uF
start cap = 17.5uF
RV Alt serial cap = 10uF
I could actually cause the swing to increase or decrease based wholly on tuning the RV PM run capacitance... I could push it into the swing big time by backing out 2-3uF and if I went beyond a certain removal of capacitance the swing would swing hard enough to sink to a 3VAC value and lose resonance. It was pretty sweet actually. The 13 uF run caps was good enough to mitigate the swing to a 94-96vac reading on the serial caps... taking out the 1uF increased this swing just a bit, such that it was going from the high 80s to near 100vac...
I measured both AC and DC current going to the batteries... the DC current was about half an amp, the AC current was .2amps from the clamp meter. It made a huge difference on the battery charging.
My next steps are to increase the serial caps again... to 3 x 15uF caps ... and then to 20uF caps to see how that works out. I was told once that using 23uF in serial on a 120V main would give me a rough thruput of 1amp at that voltage... so kinda targetting that. The good news is I know how to mitigate the swing in voltage very effectively. :)
By the way... adding 1-2uF on the run cap for the RV PM to the figures listed below removed the heavy audible swing and gave me a more constant voltage into the serial caps to the trafos.