For single phase power savings you can do easily just run about 60 uf (for 1/3hp motor), uf will have to be adjusted for best results, use a cap bank then after you find out what value works for your set up (drill press etc.) you can pick up a single cap (or two). Use 370v oil run caps. Place caps parallel to line in close to motor. Most small motors have a centrifugal start cap (or winding) and I have found no need to mess with them. This works well with my drill press and other small load motors. I could not find a big savings on my air compressor but I did have the caps at the end of the plug and have not tryed it close to the motor which seems to be desirable. A drop from 6-7amps to 2-3 amps is normal.
Jason
Thanks man, added to the compilation with your schematic, we will try and post our results. Add that duty cycle up world wide, these savings are relative. Great work thanks man.
Das ist keine wirklicher ersparniss ! Nur durch die phasenverschiebung zeit ein Watt-meter falsch an ! Normal m?ssen diese Fehl Leistungen in phase wieder korrigiert sein , die voreinen oder hinterherlaufen , damit die rechnung der E-Werke stimmt .
That is no more really save-eats! Only by the phase shift time a wattmeter wrongly on! Normally these must be again corrected wrongly achievements in phase, afterwards-run those before one or, so that the calculation of the E-works is correct.
Pese
So try it with a 12v battery to an inverter as I have. No power factor phase crap with dc and an in line amp meter.
RV knocks standard minds cold 8)
@jjbean
yes if input is DC , and output also
you find an "true" value
(if you dont have "TRUE RMS Power Meter)
otherway ,:
DC in , AC out , but let it work only to resitance OUTUT LOAD.
ike Heater (air or water) or in Light bulbs , that you can "compaire"
the Output-Power ,with another 50/60Hz or DC source.
(If Output is Sine wave . you can also see vor voltage.
R = V/A Volt divide by A are R (ohms)
Volt time Amps is VA = Watts..
Noz true if Square-Wave , Pulsed or other Curents than SINEWAVE-AC
or DC.
AC Meterings (likeyou have decribed are UNTRUE
if the PHASE of source and lode are not in same time
and direction . Your circuit have L and C.
Inductance and Capacitors in Source as in Load .
That make the problem to find TRUE power values. !
G,Pese
@pese
If AC current is not in phase with voltage than power meassured with Watt-meter is allways LOWER.
but brughtness of the lamp or mechanical power of the motor in resonance(rotoverter) with AC supply is much higher than Wattmeter would measure !!!
It is because Source Amperage Phase is in resonance with Loads Amperage Phase, and/or Source Voltage phase is in resonance with Loads Voltage Phase. Load is virtually high impendance so less current must flow through it
wizkycho2
Yes it is so.
Lamps give the view to correct output power. !
You can compair this brightness also with an second lamp that you driive
from an regulates dc source aor frm AC vario-Transformer (i think VARIAC in
US is usually word for this device).
Compare this 2 lights , and you know the power exactly.
( by eyes , by foto-brightnessmeter , lux (candle) meter
or make very simpel an "shadow" from an "match" with the
two lamps to an white paper . Lots of solutions are possibel
to find...
P.
Or you can take a 12v battery and an inline amp meter to an inverter plug in your drill press and see for yourself.
Yes but can single phase motors really be RV'ed? As far as I see it you can not. So trying an RV-alike cap approach on a single phase is not really possible except for maybe some PF correction. For true RVing you indeed need a regular 3phase motor.
Steven
For Rving a single phase, not just for power saving but actual RV mode, you need to use ? the rated voltage. Easy to do. I have had single phase 1/3hp 1725rpm 120v motors running on 4watts. (dc to inverter, no power factor). HP rating is less but rpm is slightly faster then rated.
Jason
Hello Jason,
Can you please explain to me a bit more how you rv-ed a single phase motor?
Thanks in advance
Steven
Hi Steven,
It?s pretty simple. Use a 4 to 1 trafo, 120vac in and 30vac out. Use a cap bank of 370v oil RUN caps. Put caps after trafo parallel to line and adjust to lowest current draw.
------------- -------- --- ----------
Line in [transformer] Cap cap Motor
------------- -------- --- ----------
Most small motors I have found have a start winding or capacitor that turns itself off after it is up to speed (centrifugal switch).
You know for sure you have RV effect when you have a higher circulating voltage Amperage between the cap bank and motor then you have watts from a battery to inverter. Also, a magnet vibrates violently 4? away from motor housing.
A single phase can work as alternator as well.
Jason
Thanks Jason have added that to the compilation.
here is a sch form the latest update.
Just use the 1/4 voltage rule per Hector. I would guess you could also re wire it for 120v.
I think I may have cross pollinated two things.
1st, there is running a single phase motor in ?RV? mode. This requires the step down trafo.
2nd is power savings. Is just easy to do power savings on single phase motors that can be used right away, such as your pump. You do not need the trafo, just caps. Use a switch able cap bank, say up to 80uf, 1/5 or 1uf steps or so, across both hot lines near the motor to find the value that works the best (saves you money and still have power). Then you can replace the cap bank with one or two caps of the same value. I have only tried this with ? hp and less motors. Use 370v oil ?run? caps. The docs (laymen?s and step by step) have nice explanation on how to build a cap bank (thanks Ash). My air compressor is around 1 1/2hp (I can?t recall at the moment, I?ll check) and this did not work but I was trying it at the end of the plug, not at the motor. I have confirmed on other motors that it needs to be close to the motor to work. I will try it on my well pump in my barn as well, I think it is a 1.5hp.
I have never tried anything on 230v.
Jason
Thanks for the info Jason!
Steven
Is this not the same like Hectors "Transverter" or the "Avramenko plug" ?
S
dL
@mramos
If you are using a 1.5 hp well pump in a home setting, this means your well is very deep. I have been in water treatment for over 20 years and have good experiences with pumps and wells, and that size pump is larger than ordinary indeed for a home.
So if you have a very deep well, and you RV your pump, you will get about 3/4 hp or probably less once it is RV'd and this may not be enough to give your home the proper water pressure.
Also, you should already have a pump control unit and in there you should already have a start capacitor and some control electronics.
So be careful if you play around with this type of pump with RV. I personally would not try RV for the first time on my well pump.
Based on Hectors RV and transverter stuff, I have not heard of ?Avramenko plug?.
Jason
Moderator, please delete this post. Thanks
Quote from: wattsup on August 05, 2007, 06:54:43 PM
@mramos
If you are using a 1.5 hp well pump in a home setting, this means your well is very deep. I have been in water treatment for over 20 years and have good experiences with pumps and wells, and that size pump is larger than ordinary indeed for a home.
So if you have a very deep well, and you RV your pump, you will get about 3/4 hp or probably less once it is RV'd and this may not be enough to give your home the proper water pressure.
Also, you should already have a pump control unit and in there you should already have a start capacitor and some control electronics.
So be careful if you play around with this type of pump with RV. I personally would not try RV for the first time on my well pump.
Wattsup, the Rv can deliver any horse power you want using a Freq drive
http://video.google.com.au/videoplay?docid=9089608413203959523
Catch is our HP is the most efficient power management, more Freq driven RV's should be done by others.