480 3P Fusing to VFD

Greetings experts

We are building a new machine for our test lab facility. The machine will have two (2) VFDs. The input to the VFDs is 480 3P. The VFD we are considering is the HSC03.1E-W0150. What should the fuse size be on each leg of the VFD input? Thanks.


Performance data.jpg

Thanks
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
Somewhere there should be instructions in the manual that tell you what kind of fuses or circuit breakers you can use and what the rating should be.

You also need to consider the sccr needed.
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
I wonder how they came to pick such an oddball unit. Maybe they are required to use this brand because of some European connection they have.

I think they will find they will be much better off if they pick a brand that has better US service.
 
I wonder how they came to pick such an oddball unit. Maybe they are required to use this brand because of some European connection they have.

I think they will find they will be much better off if they pick a brand that has better US service.
The motor performance that we require for this machine are very high. We have looked at all the major drive manufacturers and compared drive specs, performance data, etc, and Rexroth drives meet or exceed our requirements, where a few of the other major brands could not. Plus Rexroth drives offer EtherCAT communication protocol (another requirement we have), which again, many others (Allen Bradley, etc) don't offer.
 

Besoeker3

Senior Member
Location
UK
Occupation
Electrical Engineer
I wonder how they came to pick such an oddball unit. Maybe they are required to use this brand because of some European connection they have.

I think they will find they will be much better off if they pick a brand that has better US service.
I think you are right.
Width, height, depth - all mm.
Braking power - kW.
 

Jraef

Moderator
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
Using a VFD in the US almost always will require UL listing, which requires that the drive mfr provide the OCPD that the drive is listed with and that OCPD type is not negotiable as it is part and parcel to the listing. The size of the OCPD however may be listed as a Maximum, so you could use something smaller, but at risk of nuisance clearing.

If the drives are not UL listed, there is still likely something in the drive manual that will tell you the necessary fuses, however those fuses might be a type that is not available here. If that's the case, you will have to engage a fuse supplier to provide you with a proper cross reference based on the fuse performance curve.

OK, here is the manual:

Fuse size discussion starts on page 267 with a series of charts that relate to IEC wire sizes, so I guess you will have to convert that. But then eventually it tells you that it must be Class J for UL listing, no option for circuit breakers (which is not unusual).
 
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petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
The fuse chart also has the wire sizes listed. It is curious that the fuse size is so close to the VFD rating. Usually it is about 250%. This looks to be about 25%.

1626979539491.png
 

GeorgeB

ElectroHydraulics engineer (retired)
Location
Greenville SC
Occupation
Retired
I wonder how they came to pick such an oddball unit. Maybe they are required to use this brand because of some European connection they have.

I think they will find they will be much better off if they pick a brand that has better US service.
I worked for a Rexroth distributor in the southeast for a number of years; we sold and supported the hydraulic (classic Rexroth and BoschRexroth lines), electric (Indramat) and linear motion (Star Linear) products. Then (early 2000s) Indramat was primarily servo; there was another family of VFDs. BUT, motors were exclusively resolver commutated. They made motors for these servo systems as well.

There was domestic competition, but when our Indramat focused application engineers were involved, it was when VERY high performance was required. While I had little involvement, I was told we out-performed everyone. (Their hydraulics and electro-hydraulics were, and are, the leader; only Moog competes.)

These don't look like that calibre; however, the US support is in Charlotte NC. Facilities with both hydraulic and electric systems never complained in my presence about support being any worse than with other manufacturers.

@Jraef the manual you linked says SOME products are UL. Trying to figure what makes up what is confusing, but they at least acknowledge the requirement exists.
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
My observations on the indramat product line suggest that it is a lot like the old S5 Siemens PLC. There were a lot of European manufacturers that thought they were the cat's eye but support for them was painful and often expensive. The drives often had special application programs that either could not be moved to a replacement drive if the drive failed or doing so required some expensive help. I've also run into a couple of cases where basically indramat told our customer that the application program that was in the old drive was not supported in the new drive.

This kind of thing has made me suspicious of the whole line because what good does it do to have some special program that does something for you that can't be moved to a replacement drive?

As for the performance side of it, I don't know. A lot of the numbers seem to be Hocus pocus to me, but it's hard to tell because you have to compare apples to oranges to know if it's actually better than something else and when you get right down to it it's hard to know what you're really comparing.
 
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