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RE: 180 BPS synch, Hatachi L100 drive (fwd)
---------- 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
>>
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>
>
>
>>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
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>http://discover.aol.com/memed/aolcom30tour
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