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What size VFD for a 0.7hp motor 3phase sheetmetal nibbler?

Spud

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Jan 12, 2006
Location
Brookfield, Wisconsin
Pullmax nibbler. 3phase. 0.7 horsepower motor. Will find out voltage on Monday.

What HP rating for the VFD to run this machine off 220-240volts single phase mains supply?
If the motor is 440volts, I presume a transformer is needed to step-up the single-phase mains voltage to 440volts before it enters the VFD?



Thanks
 
Pullmax nibbler. 3phase. 0.7 horsepower motor. Will find out voltage on Monday.

What HP rating for the VFD to run this machine off 220-240volts single phase mains supply?
If the motor is 440volts, I presume a transformer is needed to step-up the single-phase mains voltage to 440volts before it enters the VFD?



Thanks

Shop around.

That small (think 3/4 HP) there are:

Several that;

- Do 2 HP on 3-P input, 1 HP on 1-P input

- others that:

- can even take input of 230 or so, use capacitor/diode "voltage doubling", and spit out up to 440 V ... or only a skosh less.

Not "free", but saves yah the space for a transformer as well as its cost.

IF the motor is actually dual-voltage capable? It ain't exactly rocket insemination to strap it for 220-240 and widen your economic choices.
 
1 HP VFDs exist, and if they have the current capability, which should not be an issue because you only need 0.7 HP, are all you need.

I would not go too high, as in much if any over 2 HP, because it begins to get hard to set the current accurately. Not all VFDs are that good as far as the current setting at lower currents relative to the max rating. They are generally most accurate at the high end of the range, near rated output.
 
I was wondering on HP rating because I know when sizing a transformer , the Kilowatts should be atleast 40% more than the max wattage the tool will pull. So was wondering if the same applied to VFDs.

So a 1.5 HP VFD should be plenty fine ?

Thermite and others:
Do all VFDs also provide step-up voltage ? If I am reading the replies right, we don't even need a transformer, can just use a VFD?


Oh and by the way, this machine is not mine, it is in our Tech School (Milwaukee Area Technical College). I am in the Autobody program, where we plan to use the machine for sheetmetal forming. I am just helping out the instructor in getting information to get it up and running and sourcing various dies. Researching inexpensive and least hassle ways to get it running, then will pass on the info to the instructor who will suggest it to the school's electrician.

The school does have 3-phase 220-240 and 600v 3 phase but the outlets are not located near where the machine is going to be, and 3 phase extension cords are a no-no. There is a 220-240 volt single phase outlet near the machine, which is what we are going to use.


So what brands would you go for? Needs to be a brand name known for safety and reliability.
ABB , Allen-Bradley, Toshiba, Hitachi, Siemens, Yaskawa ??


What do you all think of these 2 VFDs:

Yaskawa . 1.5 hp . 200-240 volt single phase input . Output 200-240v 3-phase. 6amps max load.
Yaskawa CIMR-JUBA0006BAA, 1.5 HP, 200-240V, VFD

ABB 1.5 hp. 208-240volts single phase input. Output: 240v 3-phase. 6.7amps
Buy ACS150-01U-06A7-2 - 1.5 HP ABB ACS150 Micro VFD
 
You are assuming that the motor is 230VAC, I would first get more details about the voltage and controls. Most VFDs cannot step-up the voltage, the exception is 120 input to 230VAC output 3 phase, which typically run up to 1 -1.5Hp models. A 220 to 440 VFD is uncommon, there is a UK manufacturer that I have seen these models, they tend to be expensive. At this size of machine if the motor cannot be reconnected for 230VAC, it would be cheaper to just replace the motor with say a 1 Hp motor. You need to reroute the controls so the low level VFD inputs switch on/off the motor in addition to the power disconnect.

As far as VFDs, you do not need to oversize the VFD, but you need to chceck the rated VFD output is above the motor nameplate amperage. Also on some VFDs there is a normal and a HD rating so it may be listed as say 1 HP, but only support 0.75 Hp in the HD rating. Either of the above VFDs are more than adequate, I use quite a few Yasaskawa drives,but the ABB is quite a bit less. If you do not plan to have the VFD in an enclosure, then I would go with a NEMA12 version. Teco sells a NEMA12 1 HP with a power disconnect switch built in for the same price as the Yaskawa.
Teco-Westinghouse, E510-201-H1FN4S-U, 1 HP, Variable Frequency Drive 230 Volt, 1 Phase Input, NEMA 4/4X/12, at Dealers Industrial
 
Do all VFDs also provide step-up voltage ? If I am reading the replies right, we don't even need a transformer, can just use a VFD?
Not at all. Tolja it was uncommon, but available at a bit higher price. Also only works very well in the smaller ones. But that's what you NEED.

ABB is a massive enterprise. Parts of it ain't as good as other parts.

Yaskawa has the better reputation for VFD's. Their "industrial" grade ones anyway.
Probably overkill, too, if a Teco, Hitachi, Lenze, or Weg will do yah well-enough.

Were I the appointed "SLJO" on this one? I'd probably go for a KB in NEMA 4R housing, screwdriver-adjustable instead of tiny funny-numbers.

Prolly not the greatest of VFD, but it solves a buncha side-issues, such as protective case, flexible location, shorter learning-curve and lower future messing about 'coz trimpots are damned stable as "NVRAM". Get to having the odd thunderstorm or such might require reset and start-over with an all-digital one? "No such problem".
 
Is it possible to build a 120 volt single phase in and 440 volt 3 phase out VFD without the use of any transformer in a small HP.
With my limited knowledge I'd assume a basic charge pump on the DC side but seems a big uphill jump.
All you EEs, is this doable at a reasonable current for say a 1/2 to 2 HP motor? Not asking cost effective but is it doable?
Bob
 
Is it possible to build a 120 volt single phase in and 440 volt 3 phase out VFD without the use of any transformer in a small HP.
With my limited knowledge I'd assume a basic charge pump on the DC side but seems a big uphill jump.
All you EEs, is this doable at a reasonable current for say a 1/2 to 2 HP motor? Not asking cost effective but is it doable?
Bob

Industry has been DOING that sort of stuff since time-immemorial.. or at least since High Voltage was needed on high-end o'Sopes.

It ain't cost-effective at any significant current to being with. Capacittors all age, and often rather too rapidly, higher Voltage most of all.

Line-frequency Inductors (transformers), OTOH? Tend to outlast a human generation with ease.

Where mass is a major factor, common practice is to operate smaller and lighter transformers way-to-Hell-and-gone ABOVE line frequency.

One of the numerically largest applications for that sort of HF switching?

Pee Cee Power Supplies. Stepping DOWN, not up, even.

How small? 30 years ago I had 5 VDC to 25 VDC DC-DC convertors to power RS-232 signalling needs.

Same size and PCB mounting as a 2 Watt Bournes ten-turn trimpot.

It ain't common in inverters nor VFD, mainsteeam market, because there ain't much NEED for it.

Wise makers of VFD or motors alike simply build to known available ranges of power. That only gets "hard" if they MAKE it hard.
 
1.5 HP derated to 50% is fine.

Transformer on input, going into a high voltage VFD if you need 460V.
 
Here's the Motor's specs.


Pullmax-Motor-MS-Paint-file.jpg




Since max HP is 1.2, are the the Yaskawa and ABB 1.5hp VFD sufficient?


The Yaskawa has a max amperage load of 6amps.
The ABB output current is 6.7amps
 
Yasakawa for that model species 0.75kW/5.0A under heavy duty mode, so should work but may be close to the rated limit. ABB would be much cheaper, also look at the Hitachi WJ200-15SF, Yaskawa would be a waste of money for this application. I have used KB drives, I would not use them in this application. If you want a decent low cost VFD then go with the Teco L-510.
Teco-Westinghouse, L510-202-H1, 2 HP, Variable Frequency Drive 230 Volt, 1 Phase Input, IP20, at Dea

You have a 2 speed motor so you would wire the VFD directly to the high speed (4P) motor and use the variable speed. Depending on the VFD some can be setup for 2 speed motors, but it is complicated and may not yield good results. You do not wire the VFD to the machine power and expect it to all work.
 
Yasakawa for that model species 0.75kW/5.0A under heavy duty mode, so should work but may be close to the rated limit. ABB would be much cheaper, also look at the Hitachi WJ200-15SF, Yaskawa would be a waste of money for this application. I have used KB drives, I would not use them in this application. If you want a decent low cost VFD then go with the Teco L-510.
Teco-Westinghouse, L510-202-H1, 2 HP, Variable Frequency Drive 230 Volt, 1 Phase Input, IP20, at Dea

You have a 2 speed motor so you would wire the VFD directly to the high speed (4P) motor and use the variable speed. Depending on the VFD some can be setup for 2 speed motors, but it is complicated and may not yield good results. You do not wire the VFD to the machine power and expect it to all work.


School has a decent size budget so cost is not an issue.

Main thing is that VFD will not be stressed or near its limit with machine at full power for extended periods of time. It isn't going to be at full power for more than minutes at a time but being a tech school , with new students using machine , it has to be safe, reliable and have enough reserve capacity such that overheating or failure of the VFD is never an issue.

The 2hp VFDs are pretty close to the price of the 1.5hp units. So should we go with a 2hp VFD? 2hp Hitachi is $180 , ABB around $260 and Yaskawa around $300. Is there any downside to getting a 2HP VFD?
 
No problem with 2Hp, I would go with a 2Hp unit which is a more common rating size. WJ200-15SF run around $280, so similar to ABB, either one would be a good choice. They all should do well with continuous duty. Hitachi comes with some commands locked out of the box, so you need to know how to unlock the full command set to dial in all the parameters. Have not done much with ABB, they have been around for a long time and also should be reliable.
 
The school's electrician said something about not being able to run the 3.5 amp machine because the outlet is 60amps.

The outlet was originally 3 phase 220volt (or might have been 440volt) , the electrical department split off the 3 phase into 2 single phase 220volt outlets. Right now the outlet is 220-240volts single phase 60amps

Not knowing anything about electrical stuff, is the issue that 60amp outlet is too high amperage to run a 3.5 amp machine? But the machine is not going to draw 60amps, so I am confused here.
 








 
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