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15 hp vfd for 5 hp motor on compressor

I think the PP is too rich for me this time. And it would mean junking all the sheet metal work I did here. There are also louver panels on both sides.
Keeping the box means I'm stuck with dimensions 9" 17" 9" (WHD). At present I'm at 8.5" 13" 7.75" (WHD).

My old shoe box. The vfd is not as powerful as when installed. I think I over worked it and the components had some high-end taken away.

DSC_1605.JPGDSC_1604.JPGDSC_1606.JPG

That is my reason to over compensate on the Hp issue. For example the Hitachi or Yaskawa. For $100-$200 more you get 50% higher rated devices in
the same size box. To me that is an obvious win. The AB 10 Hp 20AB028A0AYNANNN is $5500. The 15 Hp is $8360. I'm not doing that.
And then there is the "request for quote" business.
 
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You say it's 'not as powerful as when installed' - do you have numbers/data on that? Does the drive provide any indication of why it's reducing output?

I would be considering replacing the DC bus capacitors. They're the only part in most drives that I would expect to actually *degrade*, not just either work or fail. I assume cooling airflow/dust is a non-issue.
 
Stuffing that big drive into a little shoe box that small is not doing it any favors, AB makes good equipment but you need to follow the installation requirements. You could try running it with the door open to see if it can cool itself a bit better. above and below needs room for the heat to flow vertically.
 
You say it's 'not as powerful as when installed' - do you have numbers/data on that? Does the drive provide any indication of why it's reducing output?
The drive current faults after 2 sec on starting the motor with compressor belts attached. Tried lowest switching freq of 2k and with two different motors.
With no belts the motors spin up fine.
 
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Sounds like ramp rate issues, or possibly configured for variable torque (quadratic V/f) instead of constant torque (linear V/f).
I'd look at slowing the ramp rate by a second or two, and finding/enabling the function that reduces ramp rate when near current limits - most drives have an option along these lines so that the drive simply accelerates the motor as fast as it can, rather than at a pre-defined ramp rate.

Hooking it up to a PC and datalogging should also be possible.

Assuming configuration is unchanged but the drive now faults, capacitors would still be the only obvious hardware failure mode.
 
I think the parameters are as correct as can be for this drive.
- sensorless vector for constant torque applications.
- ramp time is 7 seconds. The default is 10 seconds. Will try 10 sec.
- the bus capacitors on a spare parts circuit board, four 560uF 400 V.
DSC_1609.JPG

Replacement caps:
I found this on Digi-Key. Or is it better to get a higher rating capacitor? There are ones rated for long life too.
The caps at Mouser and digi-key are all snap-in leads. My circuit board holes are smaller. So it appears that I would have to trim the snap-in leads to cylindrical.

At Mouser the lead time is at least 50 weeks. At Digikey it's only 21 weeks.

 
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Given that the buss operates at voltages up to ~340, or higher with braking, I would look for a capacitor with a higher voltage rating and also a longer lifetime rating. Unclear as to the capacitor pin mounting (4 lead or 2 lead/spacing), would need to match to the capacitor. Some examples below.
 
Yaskawa GA500, if using a 3 phase model on single phase you would need to use the GA50U2042ABA with a DC choke to get the same output ratings as the GA50UB018ABA
If I use the GA50U2056ABA (20 Hp) what size DC choke would you recommend?
This one is in a table for the 2056. Can the size of a choke be de-rated?


 
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I am doing a current GA500 install for a 5Hp vector motor to be able to run on single phase or 3 phase input. I am using the Yaskawa GA50U2042ABA and using a MTE 1uH 40A DC choke (what I had available). I saw no reason to upsize to the GA50U2056ABA. They both specify the same size DC choke: URX000261 - DC Bus Reactor, Enclosed Type 1, 200-240V, 3%, 32A, 0.85mH (MTE DCA003201). To be frank, I have done dozens of installs using the WJ200-075LF on single phase for 5Hp motors w/o a DC choke and yet to see any issues or reliability problems, they are pretty bullet proof. The Invertek single phase VFDs are also very reliable, I do not see the value of spending 2X the cost on something like the GA50U2056ABA with a DC choke for this simple application.

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This simple application... this is the fourth time since 2005.
1. single phase motor smoked.
2. replaced with second single phase motor. Worked for some years then run capacitors exploded.
3. replaced with three phase motor & vfd. Worked for a while until now. Startup and getting over-current fault.
4. new vfd

Trying to get some options. The worst would be to buy a GA50UB018ABA and it faults.
Not because it's a bad vfd. Because of the compressor pump and the long fill time.

My choices are:
Single phase in
---------------------
Yaskawa GA50UB018ABA 5 Hp $635
Invertek ODE-320153-1042 5 Hp $724

Three phase in
--------------------
Yaskawa GA50U2042ABA 15 Hp $845
Yaskawa GA50U2056ABA 20 Hp $1130
Hitachi WJ-200-110LF 15 Hp $925
Hitachi SJP1-P1-00600-LFUF 15 Hp $1007

DC Choke
--------------
 
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I have done dozens of installs using the WJ200-075LF on single phase for 5Hp motors w/o a DC choke and yet to see any issues or reliability problems, they are pretty bullet proof.
I think these are the most to least cost effective for getting more than 5 Hp.
WJ200-110LF ($50 more than the WJ200-075LF) + DC choke
GA50U2042ABA + DC choke
GA50U2056ABA + DC choke
Appreciate your help.
 
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A DC choke is not needed for the WJ200 in particular when the VFD is oversized to that degree. Single phase input VFD have beefed up input side so essentially very similar to just using an oversized 3 phase input VFD. They are designed to be run off of single phase without needing a DC choke. The GA50UB018ABA would be my first choice if you can fit it in your enclosure, then probably the WJ200. I have used both and they have been very durable. The three phase input Yaskawa's, although I use them quite a bit, I think you are paying a lot more than you need to. These drives are designed to go 24/7 for many years, I have yet to see a failure with either. The only failure I have seen with the WJ200 was with the inrush circuit failure from people switching them on/off too frequently when they should have waited at least 5 minutes for the capacitors to discharge. Yaskawa's I do not recall of any ones failing in the field. There are lots of very good VFD's these days, Fuji, Lenze, Teco, etc. that all would work well in this application.
 
I think what I really need is a little faith and a 7.5 Hp vfd normal and 5 Hp HD with single phase input.

The GA50UB018ABA is the loosest fit of them all. Very small with 5.51 5.04 7.09 (WHD) dimensions.
That is why I look up to more HP units. I think how I ruined my AB vfd was that it was running the compressor
continuously rather than giving it time to rest. Even if it is the capacitors, well it was a used vfd to start with.

At present:
GA50UB018ABA (5Hp $635
GA50U2042ABA (15 Hp) $845
GA50U2056ABA (20 Hp) $1130 on back order

My analogy for going from the 2042 to the 2056 is like installing a deep dish oil pan on a old BMW bike.
The engine might run a bit cooler with a bit longer between oil changes.
 
Actually it is larger than you indicate. The limiting factor is both the width and the depth, but the shorter height would lend itself to better cooling in your small enclosure. Yaskawa and many VFD drives indicate a clear space ~4" above and below the drive and 1" on the sides. A used VFD, the issue is often the capacitor life, both from on time, in addition to the longer it sets on the shelf. Older electrolytic capacitors deteriorate when not powered up regularly (manufactures recommend when storing VFD's at least powering up the VFD once a year for an hour or two with no load), if longer than a year the capacitors usually requiring some reforming before using the VFD. With single phase input, the outputs amps in HD mode for the GA50UB018ABA is the highest of the three from Yaskawa models you are considering, I have done system installs with all three of those models. Inventory has also been an issue, and pricing with shipping on the GA50U2056ABA is going to more than twice that of the GA50UB018ABA, and you have the additional cost of the DC choke.
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GA50UB018ABA - 17.6 A
GA50U2056ABA - 47 A knocked down to 15.2 A. What a drop for single phase input.

You ever combine a dc choke with a GA50UB018ABA?
 
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This simple application... this is the fourth time since 2005.
1. single phase motor smoked.
2. replaced with second single phase motor. Worked for some years then run capacitors exploded.
3. replaced with three phase motor & vfd. Worked for a while until now. Startup and getting over-current fault.
4. new vfd

Trying to get some options.
I would still look at the 10hp PP and just use a normal motor starter. That PP should probably get new caps and then forget about it for a long time. Then you will have real 3 phase for the entire shop, not just that compressor.
 
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A 5 Hp unit is $299.99.

Only DPS check the voltage is the output voltage 2 phase and the output voltage 3 phase when the
only motors movable

If their manuals are written by the same guy... :drink:
 
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Those appear to be a "digital" version of a static converter.

They specifically mention "no high frequency emissions", and are much too small/cheap to be much else
 
-------------------------------------------------------------
Input terminal for main power supply (R,S,T)

・This device is compatible with 3-phase
power supplies. It cannot be used with
single-phase power supplies. If single-
Prohibited phase input is required, please contact
our sales office.
・Do not operate the inverter when an input
phase is lost. Otherwise, you run the risk
of damage to the inverter.
-------------------------------------------------------------
This was from the Hitachi SJ-P1 user guide page 7-7.


I can it to mean that this applies to the drive itself or it's a general warning that might appear elsewhere.
Yet in the documentation for the WJ200 a de-rating by 2x is suggested. Double the Hp.
The SJ-P1 is supposed to replace the SJ700 but surpluscenter.com has a 10 Hp for $699. Does the stock of 16 mean that might be it?

 
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I do not know where you are going with all this, the SJ700 was discontinued many years ago. The WJ200 has been around for a long time and that be replaced with the Hitachi WJ-C1. The GA500/800 series are a replacement for the V1000 series. The DPS are nothing more than a static converter with digital circuitry to switch in the start capacitor, they self destruct when using them on a difficult load like a piston compressor. There is no 3rd leg voltage when powered up. As I indicated the GA50UB018ABA or Hitachi WJ200-075LF are reasonably priced and suitable for your application. On three phase derating, the VFD manufactures give guidance for the model and derating, if you are still unclear then just call Tech. support or the dealers and ask.

 








 
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