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Using AC Drives - was Re: 180 BPS synch, Hatachi L100 drive (fwd)
---------- Forwarded message ----------
Date: Tue, 17 Jul 2007 11:59:58 -0400
From: Jonathon Reinhart <jonathon.reinhart@xxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Using AC Drives - was Re: 180 BPS synch, Hatachi L100 drive (fwd)
Hey, do I hear talk of drives? I'm an EE co-op at a place that does R&D for
industrial machines and I've got some experience with AC drives. I had no
idea that anyone was using drives in their TC setups. Is this the case?
Also, on the subject of ABB drives... In a machine we recently pulled out of
production and re-worked, we replaced the ABB drives for conveyors with
smaller, cheaper Yaskawa drives. They are V7's. These are really nice and
I actually like them a lot. Their input freq. ref. is changeable and you
can select from 0-10V, 0-20mA, or 4-20mA. The digital operator is decent,
but they make good use out of a small 7-seg display.
I'm assuming any of these you could run from two-wire 240V? Because the
drives first convert it to straight DC.
Jonathon Reinhart
On 7/17/07, Tesla list <tesla@xxxxxxxxxx> wrote:
>
>
> ---------- Forwarded message ----------
> Date: Mon, 16 Jul 2007 21:51:22 -0700
> From: Jim Mora <jmora@xxxxxxxxxxx>
> To: 'Tesla list' <tesla@xxxxxxxxxx>
> Subject: RE: 180 BPS synch, Hatachi L100 drive
>
> Hmm, I haven't been following this thread, but I have a New Hitachi L100
> on
> my table but haven't got around yet to playing with it. Three phase motor
> control from single phase 240v. Anyone have experience with this drive?
>
> Thanks,
> Jim Mora
>
> -----Original Message-----
> From: Tesla list [mailto:tesla@xxxxxxxxxx]
> Sent: Monday, July 16, 2007 8:11 PM
> To: tesla@xxxxxxxxxx
> Subject: Re: 180 BPS synch? (fwd)
>
>
> ---------- Forwarded message ----------
> Date: Mon, 16 Jul 2007 17:51:50 -0700
> From: Barton B. Anderson <bartb@xxxxxxxxxxxxxxxx>
> To: Tesla list <tesla@xxxxxxxxxx>
> Subject: Re: 180 BPS synch? (fwd)
>
> Yes, Phil, your right, it's 4-20mA. Thanks for the correction. I'm
> probably going to replace my Altivar 31 with a brand new ABB 3 HP drive
> I have sitting on my desk. Something I've been wanting to play with but
> just haven't got around to it.
>
> Take care,
> Bart
>
> Tesla list wrote:
>
> >---------- Forwarded message ----------
> >Date: Sat, 14 Jul 2007 16:25:37 EDT
> >From: FIFTYGUY@xxxxxxx
> >To: tesla@xxxxxxxxxx
> >Subject: Re: 180 BPS synch? (fwd)
> >
> >
> >
> >In a message dated 7/14/07 9:05:52 A.M. Eastern Daylight Time,
> >tesla@xxxxxxxxxx writes:
> >
> >
> >
> >>The VFD itself is wired up to accept a 0 to 10mA signal that controls
> >>
> >>
> >
> >
> >
> >>the speed from 0 to 500 Hz.
> >>
> >>
> >
> > Shouldn't that be 4-20mA? One of the advantages of a 4-20mA current
> loop
> >signal is to avoid the noise of zero mA meaning "zero signal". Hence the
> >minimum 4 mA...
> >
> >
> >
> >>I use an Altivar 31 VFD by Telemecanique. Telemecanique was once known
> >>
> >>
> >
> >
> >
> >>as "not the greatest of VFDs". That has changed in the past 4 years.
> The
> >>
> >>
> >
> >
> >
> >>company actually was revamped. Nowadays, their drives are probably the
> >>
> >>
> >
> >
> >
> >>easiest to use and are now very reliable. Especially the Altivar 31
> >>
> >>
> >
> >
> >
> >>series (versus the old Altivar 28 which was pure Telemecanique of old).
> >>
> >>
> >
> >
> >
> >Now that I've finished laughing so hard that I had to pick myself up the
> >floor, I find myself wondering if you're actually *serious*!
> > I finished replacing the fourth ATV 31 drive (from 2kW to 15kW) in a
> >brand new installation. Four drives in less than a year of operation? I
> >cannibalized all of them. Most failed due to the "brick" having bad
> connections. They
> >went to a design that clamps down, so the brick leads spring against
> pads
> on
> >the circuit board, instead of bolting or soldering to connections to it.
> One
> >had a blown input rectifier, which when replaced allowed control and
> display
> >power but the output was still dead as a doornail (even though the
> display
>
> >told me it was running OK).
> > "Easiest to use"? Are you kidding??? Where do I start... no local
> keypad
> >jog function, no local/remote key on keypad, no easy-to-replace keypad
> >(without disassembling the drive), no parameter storage in keypad, no
> built-in
> >line or load reactors, no provision for external powering/switching of
> cooling
> >fan, no built-in macros for common user applications, a *very* primitive
> LED
> >display (three letter codes derived from 7-segment LED's, and the codes
> are in
> >French/IEC abbreviations), no standard provision for encoder interface,
> >included hard copy manual is minimal.
> > IMHO the only thing I like about Telemecanique is their cable safety
> >switches (which they pioneered). If it's Tele, you name it, I've worked
> with it.
> >I tried to get an Alitvar 41 (IIRC) which was a very cost-effective
> drive.
> I
> >needed a 20kW for a fan application, and they don't make 31's bigger
> than
> >15kW. We got a great price break from our vendor on Tele crap, and I
> wanted to
> >keep things standardized. But apparently although they list that product
> on
> >the Tele website, they only offer it in Europe.
> >
> >
> >
> >
> >>when it comes to motor control, 3-phase is industry standard and VFD's
> are
> >>their industry standard control module.
> >>
> >>
> >
> > Depends very much on the industry! I've seen two brand-new printing
> >presses built and installed at two different local factories in the last
> two
> >years that both had 40+ HP *DC* motors as the main drive! I've worked on
> all
> >brands and vintages of those things, and can say with no reservation
> that
> a DC
> >motor is a complete waste (and liability!) for that application. But it
> seems
> >that's all the "old" engineers will trust. Shame, I've seen tiny AC
> motors
> run
> >big presses, and spec'ed and installed a big 60 HP AC motor and C-H
> SV9000
>
> >drive on an old press. Both run flawlessly...
> > Some places still use a lot of single phase motors for smaller loads
> and
> >machine automation. Steppers are popular for slow-speed positioners. On
> that
> >note, I've seen plenty of brand-new DC servos on new equipment.
> >
> >
> >
> >>In motor control, Allen Bradley is still top of line for VFD's.
> >>
> >>
> >
> > Are you trying to kill me with laughter, Bart? :)
> > Their new Powerflex line is interesting, but you can keep your
> 1305's
> >and 1336's. Too many problems with those in too many applications to
> list
> here.
> > OTOH, A-B is the "Dark Side" of Rockwell Automation. Reliance has
> always
> >made very tough stuff. I've seen old Reliance drives, of all types,
> >soldiering on long after they've become obsolete. They still seem to
> make
> a very
> >tough AC drive with a good reputation. I wish I've had more than a
> passing
> chance
> >to work with modern Reliance AC drives, so I could confirm my good
> >impression.
> >
> >
> >
> >>But the others now are right there with them in capability. The main
> >>
> >>
> >difference is that industries are >tied into a particular breed by the
> code they
> >write. It would be an expensive task
> >
> >
> >
> >>to change over to something else. So, they stick with what they are
> >>
> >>
> >
> >
> >
> >>familiar with. I do the same. I understand that situation completely.
> >>
> >>
> >
> >
> >
> > True, and nothing can make or break you like being tied to a
> particular
> >brand by nothing more than a salesperson or engineer's inconsiderate
> >preference (usually a kickback).
> >
> > IMHO the Cutler-Hammer SV(X)9000 drives have given me the best luck
> over
>
> >the long run, although the manual is a bit difficult in places. Sumitomo
> >drives were built like a battleship. ABB makes a very nice
> and affordable
> AC
> >drive, but their DC drives are a nightmare. Baldor drives are very
> user-friendly,
> >but always seem to have issues with control power supplies. Eurotherm
> drives
> >are *way* over-engineered for programming options (difficult to
> commission),
> >and not robust enough. Hitachi and Mitsubishi AC drives are about the
> >cheapest I've found, and seem to do fine.
> >
> >-Phil LaBudde
> >Center for the Advanced Study of Ballistic Improbabilities
> >
> >
> >
> >************************************** Get a sneak peak of the all-new
> AOL
> at
> >http://discover.aol.com/memed/aolcom30tour
> >
> >
> >
> >
> >
> >
> >
>
>
>
>
>
>
>
>