single phase to 3 phase converters
lazza
Solar Expert Posts: 336 ✭✭✭
HI Forum
We've been looking at powering some farm buildings. The problem is that although most of the equipment is single phase, there is a small 3-phase pump for irrigation (around 300W), that needs to be powered.
Are there reliable single phase to 3-phase inverters that can resolve this issue??
thanks
Larry
We've been looking at powering some farm buildings. The problem is that although most of the equipment is single phase, there is a small 3-phase pump for irrigation (around 300W), that needs to be powered.
Are there reliable single phase to 3-phase inverters that can resolve this issue??
thanks
Larry
Comments
-
Re: single phase to 3 phase converters
You may consider one of these single to three-pahse voltage transformers: [h=3]http://www.mcmaster.com/#rotary-phase-converters/=uhpxww[/h]Cheers!Off-grid cabin in northern Quebec: 6 x 250 W Conergy panels, FM80, 4 x 6V CR430 in series (24V nominal), Magnum MS4024-PAE -
Re: single phase to 3 phase convertersHI Forum
We've been looking at powering some farm buildings. The problem is that although most of the equipment is single phase, there is a small 3-phase pump for irrigation (around 300W), that needs to be powered.
Are there reliable single phase to 3-phase inverters that can resolve this issue??
thanks
Larry
1. A rotary phase converter (not a simple transformer, since it relies on moving parts.) More like a motor generator in which the motor and the generator share windings. Kind of like the way an autotransformer works. :-)
2. A solid state converter. For a small motor, the least expensive way to get this, and one which gives you the added advantage of soft start, would be to get a Variable Frequency Drive (VFD). By following the manufacturer's ratings and instructions you can drive a VFD from a single phase source.SMA SB 3000, old BP panels. -
Re: single phase to 3 phase converters
ramloui posted information about "rotary phase converters"...
More or less, take a three phase motor and connect it to a single phase power supply. Start the motor turning (pull on a rope wrapped around the output shaft, or use a capacitor start module).
Once the 3 phase "rotary converter" is up to speed, you can now take the three wires from the converter and connect them to other 3 phase motors. The rotary converter acts a bit like a "motor generator" and supplies the missing "phases".
These work surprisingly well. Helped a friend build an entire machine shop filled with 1-5 HP (1-4 kWatt) 3 phase motors off of single phase 240 VAC power. Ran everything off a 3 phase 5 HP motor (even used a small motor and belt to get the three phase motor up to speed originally).
If the three phase 300 Watt motor is not heavily loaded, you can get single to 3 phase starter/controllers (capacitor+voltage sensing relay). Starts the three phase motor and then the motor runs on single phase AC--Will also work pretty well (make sure the motor does not pull too much current on its single phase and overheat, may also have lower starting torque--So for positive displacement pumps, may have trouble starting).
http://www.phase-a-matic.com/StaticDescription.htm
There is a lot of information on the web and you can build them yourself.
The rotary phase converter does waste a lot of energy--May not be the best choice for off grid power system (unless it is relatively small vs overall system size, hours of use per day).
The "Static Converter" works very well, but you need to "derate" the motor to lower output power (to prevent drawing too much current and overheating/difficulties starting).
Lastly, there is the VFD (variable frequency drive). Get a single phase in, 3 phase out. Would probably be a very good solution to your problem.
Of course, it appears that VFDs are MSW output (modified square wave) for the most part, which can be hard on induction motors (single or three phase), so monitor the motor's running temperature on the VFD to make sure it does not overheat. And/or replace with motor rated to run on a VFD.
-BillNear San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset -
Re: single phase to 3 phase convertersHI Forum
there is a small 3-phase pump for irrigation (around 300W), that needs to be powered.
Are there reliable single phase to 3-phase inverters that can resolve this issue??
thanks
Larry
For only one 3 phase 300w pump , I'd change the motor drive to single phase , for the 3 phase converter idea , huge waste in converting ..
VT -
Re: single phase to 3 phase converters
Hi, thanks for all your replies
I'm leaning towards either a solid state converter or changing the motor of the pump-
Does changing the pump motor mean rewiring, or buying a new motor? -
Re: single phase to 3 phase converters
You will need a new motor. Do you have a picture of the pump or of the face plate on the pump motor showing the specs? -
Re: single phase to 3 phase converters
Not yet, but may be able to get a pic this week -
Re: single phase to 3 phase converters
Small VF drives that can take single phase in and put three phase out are cheap. They also can usually be programmed for a soft ramp start which reduces surge load which is important for a off grid load. Depending on your application you can run the pump at lower output speed which will reduce pump cycling. Most new household pump applications are variable speed pumps that vary speed to maintain flow rather than using a pressure tank.
Categories
- All Categories
- 222 Forum & Website
- 130 Solar Forum News and Announcements
- 1.3K Solar News, Reviews, & Product Announcements
- 191 Solar Information links & sources, event announcements
- 887 Solar Product Reviews & Opinions
- 254 Solar Skeptics, Hype, & Scams Corner
- 22.3K Solar Electric Power, Wind Power & Balance of System
- 3.5K General Solar Power Topics
- 6.7K Solar Beginners Corner
- 1K PV Installers Forum - NEC, Wiring, Installation
- 2K Advanced Solar Electric Technical Forum
- 5.5K Off Grid Solar & Battery Systems
- 425 Caravan, Recreational Vehicle, and Marine Power Systems
- 1.1K Grid Tie and Grid Interactive Systems
- 651 Solar Water Pumping
- 815 Wind Power Generation
- 622 Energy Use & Conservation
- 608 Discussion Forums/Café
- 302 In the Weeds--Member's Choice
- 74 Construction
- 124 New Battery Technologies
- 108 Old Battery Tech Discussions
- 3.8K Solar News - Automatic Feed
- 3.8K Solar Energy News RSS Feed