Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i

On Sat, 28 Aug 2010 19:31:16 -0500, Ignoramus5734
wrote:

Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i

The secret to lektrik stuff is magic smoke. If you let it out, it
don't work no more.

Buy another on the bay.

On Aug 28, 5:45*pm, Karl Townsend
wrote:
On Sat, 28 Aug 2010 19:31:16 -0500, Ignoramus5734

wrote:
Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i

The secret to lektrik stuff is magic smoke. If you let it out, it
don't work no more.

Buy another on the bay.

Unlike individual transistors, ICs usually die from their own internal
problems. Usually too much heat and not enough heat sink. Can you
determine the Id of the victim?

Paul

On Sat, 28 Aug 2010 19:31:16 -0500, Ignoramus5734
wrote:

Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i

Find out which chip it is..and what could have killed it. Normally
chips dont get blackened without a serious serious issue.

Gunner


I am the Sword of my Family
and the Shield of my Nation.
If sent, I will crush everything you have built,
burn everything you love,
and kill every one of you.
(Hebrew quote)

On Sat, 28 Aug 2010 19:45:53 -0500, Karl Townsend
wrote:

On Sat, 28 Aug 2010 19:31:16 -0500, Ignoramus5734
wrote:

Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i

The secret to lektrik stuff is magic smoke. If you let it out, it
don't work no more.

Buy another on the bay.

It's no longer available via eBay. Here is another source:
http://www.mez.co.uk/lucas.html

--
If we attend continually and promptly to the little that we can do,
we shall ere long be surprised to find how little remains that we
cannot do. -- Samuel Butler

I just replaced my shop computer motherboard because of one chip failed.
The Disk controller for SATA drives got a hot corner. The temp here has
been hot, but I try not to use it when I don't have refrig air blowing on it.

It started telling me bad disk drive. Force reformat and re-install - only
to die. Buy a brand new disk - that one failed likewise. Hum - bit issues.

New mother board, both disks format and function as they should.

It was the only LSI chip there without a heat sink. Now a INTEL motherboard
is in and sigh - looks like I'm looking for heat sink epoxy.

Anyone know of any easy to find without buying gold-epoxy ?

No mounting holes for a sink - and I think one will help.

I have a HD screen - with dual inputs - Got a low cost HD video card -
and wow is that nice to look at now!

Martin

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
"Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Originator & Charter Founder
IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com/

On 8/28/2010 7:31 PM, Ignoramus5734 wrote:
Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i

On Sat, 28 Aug 2010 21:22:24 -0500, "Martin H. Eastburn"
wrote:

I just replaced my shop computer motherboard because of one chip failed.
The Disk controller for SATA drives got a hot corner. The temp here has
been hot, but I try not to use it when I don't have refrig air blowing on it.

It started telling me bad disk drive. Force reformat and re-install - only
to die. Buy a brand new disk - that one failed likewise. Hum - bit issues.

New mother board, both disks format and function as they should.

It was the only LSI chip there without a heat sink. Now a INTEL motherboard
is in and sigh - looks like I'm looking for heat sink epoxy.

Anyone know of any easy to find without buying gold-epoxy ?

No mounting holes for a sink - and I think one will help.

Why not just put a small fan in the case aimed at the chip?


I have a HD screen - with dual inputs - Got a low cost HD video card -
and wow is that nice to look at now!

Martin

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
"Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Originator & Charter Founder
IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com/

On 8/28/2010 7:31 PM, Ignoramus5734 wrote:
Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i


I am the Sword of my Family
and the Shield of my Nation.
If sent, I will crush everything you have built,
burn everything you love,
and kill every one of you.
(Hebrew quote)

On Sat, 28 Aug 2010 18:19:21 -0700 (PDT), the renowned
" wrote:

On Aug 28, 5:45*pm, Karl Townsend
wrote:
On Sat, 28 Aug 2010 19:31:16 -0500, Ignoramus5734

wrote:
Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i

The secret to lektrik stuff is magic smoke. If you let it out, it
don't work no more.

Buy another on the bay.

Unlike individual transistors, ICs usually die from their own internal
problems. Usually too much heat and not enough heat sink. Can you
determine the Id of the victim?

Paul

All common CMOS chips have a giant parasitic SCR living inside them..
hit it with some static electricity and it can turn on and the chip
will destroy itself if there is enough power supply current available.
The term is "latch up". Modern chips are much more resistant than
older ones, but it can still happen.

Good designs protect the chips from obvious things like connectors
that go to the outside world using external parts (resistors, discrete
transistors, optoisolators that sort of thing), but if a part is
touched on a powered board it can die.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

Ignoramus5734 wrote:
Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i

Whose servo amp? Can you tell by location what that chip is connected to?
Check another to get the part number of the burned chip.

Jon

On 2010-08-29, Jon Elson wrote:
Ignoramus5734 wrote:
Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i

Whose servo amp? Can you tell by location what that chip is connected to?
Check another to get the part number of the burned chip.

That was am AMC 30A8 amplifier, revision T.

The chips on them mostly do not have markings, this one was a small
one in the middle of the motherboard.

I really like the drives, their simplicity, cost and support from
AMC. I do not know if I can guess the cause. But, possibly,
interference again is to blame. I have, since, routed the twisted DC
motor cables away from control stuff.

You mentioned ferrite cores to place on these cables. Would you
suggest any particular Digikey part number?

Thanks

i

What's that Lassie? You say that Martin H. Eastburn fell down the old
rec.crafts.metalworking mine and will die if we don't mount a rescue
by Sat, 28 Aug 2010 21:22:24 -0500:

It was the only LSI chip there without a heat sink. Now a INTEL motherboard
is in and sigh - looks like I'm looking for heat sink epoxy.

Anyone know of any easy to find without buying gold-epoxy ?

http://www.arcticsilver.com/products.htm
http://www.arcticsilver.com/usa_resellers.htm
--

Dan H.
northshore MA.

Ignoramus5734 on Sat, 28 Aug 2010
19:31:16 -0500 typed in rec.crafts.metalworking the following:
Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

Ah, it sounds like you let the magical smoke out of the chip.
That's the real secret of electronic equipment, it really runs on
smoke.
Just don't let the smoke catch fire. That's ...bad.

You might want to "add more fans" in order to increase airflow,
and hopefully cooling.

i
--
pyotr filipivich
We will drink no whiskey before its nine.
It's eight fifty eight. Close enough!

"Ignoramus5734" wrote in message
...
On 2010-08-29, Jon Elson wrote:
Ignoramus5734 wrote:
Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i

Whose servo amp? Can you tell by location what that chip is connected
to?
Check another to get the part number of the burned chip.

That was am AMC 30A8 amplifier, revision T.

The chips on them mostly do not have markings, this one was a small
one in the middle of the motherboard.

I really like the drives, their simplicity, cost and support from
AMC. I do not know if I can guess the cause. But, possibly,
interference again is to blame. I have, since, routed the twisted DC
motor cables away from control stuff.

You mentioned ferrite cores to place on these cables. Would you
suggest any particular Digikey part number?


Its a garden variety 15-30 brush amp which when reduced to basic specs are
about as common as dirt.

The 30amp peak spec is probly wishful thinking--at the least it's gross
overkill for a bridgeport sized mill

--personally I would look at the "copley controls" and / or servo dynamics
offerings on ebay....most likely you are running in velocity mode (ie it has
a tach feedback dedicated to velocity control as well as having resolver or
encoder for on-the-fly and final-in-position check/ verify ) and so suggest
make sure there is an actual pot to adjust your tach gain because sometimes
a fixed resistor is substituted where some OEM has dedicated to a specific
motor for instance glentec which used 7 volts per KRPM but the tach output
on your particular motors might well completely out of that ballpark hence
the additional dash numbers ( revisions )

1525 brush amps are pretty near a dime a dozen these days--invest a little
time in research and you can be an expert it's not ****ing rocket science.

"PrecisionmachinisT" wrote in message
...

"Ignoramus5734" wrote in message
...
On 2010-08-29, Jon Elson wrote:
Ignoramus5734 wrote:
Since yesterday, I had the Z axis behaving very weirdly, suddenly
lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo
drive.

Since I have several additional drives on the shelf (they were
cheap),
I swapped one for another. Now the Z axis is back to working. I
opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i

Whose servo amp? Can you tell by location what that chip is connected
to?
Check another to get the part number of the burned chip.

That was am AMC 30A8 amplifier, revision T.

The chips on them mostly do not have markings, this one was a small
one in the middle of the motherboard.

I really like the drives, their simplicity, cost and support from
AMC. I do not know if I can guess the cause. But, possibly,
interference again is to blame. I have, since, routed the twisted DC
motor cables away from control stuff.

You mentioned ferrite cores to place on these cables. Would you
suggest any particular Digikey part number?


Its a garden variety 15-30 brush amp which when reduced to basic specs are
about as common as dirt.

The 30amp peak spec is probly wishful thinking--at the least it's gross
overkill for a bridgeport sized mill

--personally I would look at the "copley controls" and / or servo dynamics
offerings on ebay....most likely you are running in velocity mode (ie it
has
a tach feedback dedicated to velocity control as well as having resolver
or
encoder for on-the-fly and final-in-position check/ verify ) and so
suggest
make sure there is an actual pot to adjust your tach gain because
sometimes
a fixed resistor is substituted where some OEM has dedicated to a specific
motor for instance glentec which used 7 volts per KRPM but the tach output
on your particular motors might well completely out of that ballpark hence
the additional dash numbers ( revisions )

1525 brush amps are pretty near a dime a dozen these days--invest a little
time in research and you can be an expert it's not ****ing rocket science.


One other thing....

The amps which spec out as using an AC 110 input are also fair game here
because they are basically your standard DC input unit except they also have
an additional power supply which is typically built-in to the upper sheet
metal heat sink cover.

--remove said cover, detach the leads from the barrier strip and toss--now,
attach the red and black from YOUR existing DC power suppy buss to the amp
instead and all is good so long as your existing supply output is 140 dc or
less.

--

Buy another on the bay.

It's no longer available via eBay. Here is another source:
http://www.mez.co.uk/lucas.html

ROTFLMOA Got tears coming out of my eyes.

I used to own a british car with Lucas wiring. Triumph TR4a

On Sun, 29 Aug 2010 04:50:25 -0500, Karl Townsend
wrote:


Buy another on the bay.

It's no longer available via eBay. Here is another source:
http://www.mez.co.uk/lucas.html

ROTFLMOA Got tears coming out of my eyes.

I used to own a british car with Lucas wiring. Triumph TR4a

Ever, perchance, have a grounding problem wi that wee beastie, Karl?

--
If we attend continually and promptly to the little that we can do,
we shall ere long be surprised to find how little remains that we
cannot do. -- Samuel Butler

It's no longer available via eBay. Here is another source:
http://www.mez.co.uk/lucas.html

ROTFLMOA Got tears coming out of my eyes.

I used to own a british car with Lucas wiring. Triumph TR4a

Ever, perchance, have a grounding problem wi that wee beastie, Karl?

i owned that car four years. it was under repair for two of those
years. AND it was my only car. I about split a gasket over the
official lucas three way switch - dim,flicker, off. I put in all new
wires for the starter and iginition. The rest of it normally didn't
run.

karl

On Aug 28, 8:58*pm, Ignoramus5734
wrote:

Whose servo amp? *Can you tell by location what that chip is connected to?
Check another to get the part number of the burned chip.

That was am AMC 30A8 amplifier, revision T.

The chips on them mostly do not have markings, this one was a small
one in the middle of the motherboard.

I really like the drives, their simplicity, cost and support from
AMC. I do not know if I can guess the cause. But, possibly,
interference again is to blame. I have, since, routed the twisted DC
motor cables away from control stuff.

You mentioned ferrite cores to place on these cables. Would you
suggest any particular Digikey part number?

Thanks

i

Did you follow the suggested wiring scheme?

http://www.a-m-c.com/download/manual...tallManual.pdf

Paul

"Martin H. Eastburn" wrote in message
...
I just replaced my shop computer motherboard because of one chip failed.
The Disk controller for SATA drives got a hot corner. The temp here has
been hot, but I try not to use it when I don't have refrig air blowing on
it.

It started telling me bad disk drive. Force reformat and re-install -
only
to die. Buy a brand new disk - that one failed likewise. Hum - bit
issues.

New mother board, both disks format and function as they should.

It was the only LSI chip there without a heat sink. Now a INTEL
motherboard
is in and sigh - looks like I'm looking for heat sink epoxy.

Anyone know of any easy to find without buying gold-epoxy ?

Arctic Silver Thermal Epoxy. Do Google. Several vendors have it in stock.
I've got a couple half tubes sitting on my desk.

Karl Townsend wrote:
Buy another on the bay.

It's no longer available via eBay. Here is another source:
http://www.mez.co.uk/lucas.html


ROTFLMOA Got tears coming out of my eyes.

I used to own a british car with Lucas wiring. Triumph TR4a

I rebuilt several TR3's in my youth. Saved the cable to the starter
motor and battery ground
cable, and most of the switches, etc, especially ignition switch,
headlight switch and dimmer
switch. Pretty much everything else had to go, and totally rewired
everything with that new-fangled
plastic-covered wire. With the cloth-covered wire, exposed to oil and
moisture, the stuff just disintegrated
completely.

Jon

Ignoramus5734 wrote:
That was am AMC 30A8 amplifier, revision T.

The chips on them mostly do not have markings, this one was a small
one in the middle of the motherboard.

I really like the drives, their simplicity, cost and support from
AMC. I do not know if I can guess the cause. But, possibly,
interference again is to blame.
VERY unlikely.
You mentioned ferrite cores to place on these cables. Would you
suggest any particular Digikey part number?

Sorry, I really don't have a part number. You might check old computer
cables for those
bulges in them, those are big ferrite rings for noise isolation. You
want to run both
motor cables through the same core, so they are not exposed to the motor
current
(the current in the two wires cancels out).

Jon

PrecisionmachinisT wrote:

--personally I would look at the "copley controls"
Copley Controls and AMC amps are identical. Not sure who makes them for
who, but
it is pretty clear if you look closely that they are the same unit with
different labels.

Jon

In article ,
Jon Elson wrote:

Ignoramus5734 wrote:
That was am AMC 30A8 amplifier, revision T.

The chips on them mostly do not have markings, this one was a small
one in the middle of the motherboard.

I really like the drives, their simplicity, cost and support from
AMC. I do not know if I can guess the cause. But, possibly,
interference again is to blame.

VERY unlikely.

Agree.


You mentioned ferrite cores to place on these cables. Would you
suggest any particular Digikey part number?

Sorry, I really don't have a part number. You might check old computer
cables for those
bulges in them, those are big ferrite rings for noise isolation. You
want to run both
motor cables through the same core, so they are not exposed to the motor
current
(the current in the two wires cancels out).

The split-sleeve emi-filter chokes are what Iggy seeks. Here is an example:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=240-2131-ND


However, these chokes really are not that effective compared to real shielding.
I would first shield the motor power leads, as they are very high power.

Joe

Joe, I will get a shielded cable for the motor leads, and will ground
the cable, and will also add those filters. If I recall correctly, the
cables from the motors connected to the main terminal block, are not
that shielded, so if I shield the cables going from drives to terminal
block, it is only half the battle.

i

On Aug 28, 10:00*pm, Larry Jaques
wrote:
On Sat, 28 Aug 2010 19:45:53 -0500, Karl Townsend





wrote:
On Sat, 28 Aug 2010 19:31:16 -0500, Ignoramus5734
wrote:

Since yesterday, I had the Z axis behaving very weirdly, suddenly lots
of chatter and vibration, extremely erratic behavior, then no motion
at all, then some motion etc.

Attempting to diagnose it (isolate the issue) pointed to a servo drive.

Since I have several additional drives on the shelf (they were cheap),
I swapped one for another. Now the Z axis is back to working. I opened
up the drive that I relpaced and saw one chip blackened.

Not sure what to make of this.

i

The secret to lektrik stuff is magic smoke. If you let it out, it
don't work no more.

Buy another on the bay.

It's no longer available via eBay. *Here is another source:http://www.mez.co.uk/lucas.html

--
If we attend continually and promptly to the little that we can do,
we shall ere long be surprised to find how little remains that we
cannot do. * * * * * * * * * * * * * * * * * * * *-- Samuel Butler- Hide quoted text -

- Show quoted text -

Good one. I used to earn my living working on british bikes, trying to
keep the smoke in.

Ignoramus24925 wrote:

Joe, I will get a shielded cable for the motor leads, and will ground
the cable, and will also add those filters. If I recall correctly, the
cables from the motors connected to the main terminal block, are not
that shielded, so if I shield the cables going from drives to terminal
block, it is only half the battle.

i

You can get flexible metal conduit (Greenfield) at Depot or Lowe's and
fish your motor (both spindle and servos) through the conduit to provide
shielding. It's cheap stuff, I just got a 25' roll of 1/2" FMC at Depot
for $10. They also have 3/8" size which may be better for the servo
power leads.

On Mon, 30 Aug 2010 00:45:50 -0500, Jon Elson
wrote:

PrecisionmachinisT wrote:

--personally I would look at the "copley controls"
Copley Controls and AMC amps are identical. Not sure who makes them for
who, but
it is pretty clear if you look closely that they are the same unit with
different labels.

They sure do look alike, but they're not the same. There are subtle
differences in the dimensions and connections, and some significant
differences in the setup options after you pop the cover.

--
Ned Simmons

"Jon Elson" wrote in message
...
PrecisionmachinisT wrote:

--personally I would look at the "copley controls"
Copley Controls and AMC amps are identical. Not sure who makes them for
who, but
it is pretty clear if you look closely that they are the same unit with
different labels.


The reason I brought up the name "Copley" is because there's generally a
favorable difference in price--at least when it comes to the used amps on
ebay....but yes, it's fairly common for these things to be assembled under
contract by a "competitor" and then re-labled.

--

I bought some from Amazon - they have a vendor that sells it - but
via Amazon. I get free shipping from the Big A - otherwise there are
other vendors. IIRC, it is a Intel design/developed - maybe just approved.

I'm gluing a heat sink on my SATA drive chip. It burned up on the last
motherboard in the shop.

And thanks for the input.

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
"Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Originator & Charter Founder
IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com/

On 8/29/2010 10:32 PM, Bob La Londe wrote:


"Martin H. Eastburn" wrote in message
...
I just replaced my shop computer motherboard because of one chip failed.
The Disk controller for SATA drives got a hot corner. The temp here has
been hot, but I try not to use it when I don't have refrig air blowing on it.

It started telling me bad disk drive. Force reformat and re-install - only
to die. Buy a brand new disk - that one failed likewise. Hum - bit issues.

New mother board, both disks format and function as they should.

It was the only LSI chip there without a heat sink. Now a INTEL motherboard
is in and sigh - looks like I'm looking for heat sink epoxy.

Anyone know of any easy to find without buying gold-epoxy ?

Arctic Silver Thermal Epoxy. Do Google. Several vendors have it in stock. I've
got a couple half tubes sitting on my desk.

In article .com,
"Pete C." wrote:

Ignoramus24925 wrote:

Joe, I will get a shielded cable for the motor leads, and will ground
the cable, and will also add those filters. If I recall correctly, the
cables from the motors connected to the main terminal block, are not
that shielded, so if I shield the cables going from drives to terminal
block, it is only half the battle.

i

You can get flexible metal conduit (Greenfield) at Depot or Lowe's and
fish your motor (both spindle and servos) through the conduit to provide
shielding. It's cheap stuff, I just got a 25' roll of 1/2" FMC at Depot
for $10. They also have 3/8" size which may be better for the servo
power leads.

Either will work. As will regular conduit in areas not requiring flexibility.
Nor is there any harm in doing both shielded wire and conduit, although there is
no electrical advantage either. Greenfield and conduit are immune to hot chips
melting a hole, though.

It's important to ground the shield where it passes through a shield wall, like
the motor case and the cabinet where the VFD lives. If the VFD isn't in a metal
cabinet, then ground the VFD end to the frame of the VFD.

For the record, this VFD ground is an extension of the safety (green/bare)
ground system, and not the neutral (white).

I'm suspicious of the VFD terminal block - it may be the power neutral, versus
the safety ground. The VFD frame ground (usually with green screw) is safe and
correct.

They also make line inductors that go between VFD and motor that reduce
interference by reducing the edge speed of the switched waveform that the motor
sees as a varying-frequency sine wave. However, such inductors are very big and
expensive, and very unlikely to be needed for such a small motor. (I have no
such thing on my VFDs.)

Joe Gwinn

On 2010-08-30, Jon Elson wrote:
Ignoramus5734 wrote:
That was am AMC 30A8 amplifier, revision T.

The chips on them mostly do not have markings, this one was a small
one in the middle of the motherboard.

I really like the drives, their simplicity, cost and support from
AMC. I do not know if I can guess the cause. But, possibly,
interference again is to blame.
VERY unlikely.
You mentioned ferrite cores to place on these cables. Would you
suggest any particular Digikey part number?

Sorry, I really don't have a part number. You might check old
computer cables for those bulges in them, those are big ferrite
rings for noise isolation. You want to run both motor cables
through the same core, so they are not exposed to the motor current
(the current in the two wires cancels out).

Jon, I bought some of those rings at digikey, they were
inexpensive. Item 240-2131-ND.

So you say, basically, just put a pair wires through the hole of one
ring, right?

i

On 2010-08-30, Joseph Gwinn wrote:
In article ,
Jon Elson wrote:

Ignoramus5734 wrote:
That was am AMC 30A8 amplifier, revision T.

The chips on them mostly do not have markings, this one was a small
one in the middle of the motherboard.

I really like the drives, their simplicity, cost and support from
AMC. I do not know if I can guess the cause. But, possibly,
interference again is to blame.

VERY unlikely.

Agree.


You mentioned ferrite cores to place on these cables. Would you
suggest any particular Digikey part number?

Sorry, I really don't have a part number. You might check old computer
cables for those
bulges in them, those are big ferrite rings for noise isolation. You
want to run both
motor cables through the same core, so they are not exposed to the motor
current
(the current in the two wires cancels out).

The split-sleeve emi-filter chokes are what Iggy seeks. Here is an example:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=240-2131-ND


However, these chokes really are not that effective compared to real shielding.
I would first shield the motor power leads, as they are very high power.

Joe, I bought those rings. I will shield the wires going to the big
terminal block from the drives, (and ground the shield) and would put
the rings on the wires going out of the terminal block to the motors.

i

In article ,
Ignoramus24760 wrote:

On 2010-08-30, Joseph Gwinn wrote:
In article ,
Jon Elson wrote:

Ignoramus5734 wrote:
That was am AMC 30A8 amplifier, revision T.

The chips on them mostly do not have markings, this one was a small
one in the middle of the motherboard.

I really like the drives, their simplicity, cost and support from
AMC. I do not know if I can guess the cause. But, possibly,
interference again is to blame.

VERY unlikely.

Agree.


You mentioned ferrite cores to place on these cables. Would you
suggest any particular Digikey part number?

Sorry, I really don't have a part number. You might check old computer
cables for those
bulges in them, those are big ferrite rings for noise isolation. You
want to run both
motor cables through the same core, so they are not exposed to the motor
current
(the current in the two wires cancels out).

The split-sleeve emi-filter chokes are what Iggy seeks. Here is an
example:

http://search.digikey.com/scripts/Dk...me=240-2131-ND



However, these chokes really are not that effective compared to real
shielding.
I would first shield the motor power leads, as they are very high power.

Joe, I bought those rings. I will shield the wires going to the big
terminal block from the drives, (and ground the shield) and would put
the rings on the wires going out of the terminal block to the motors.

Cheap enough to just try. One normally puts all three (or four) motor leads
through the same core, so the power-frequency magnetic fields largely cancel, to
avoid magnetic saturation of the ferrite. One can put multiple cores on the
same cable, one after another. Nor will anything bad or permanent happen if you
do put a single wire through a core, perhaps saturating the ferrite, so there is
no reason not to try everything.

Joe Gwinn

On 2010-09-03, Joseph Gwinn wrote:
In article ,
Ignoramus24760 wrote:

On 2010-08-30, Joseph Gwinn wrote:
In article ,
Jon Elson wrote:

Ignoramus5734 wrote:
That was am AMC 30A8 amplifier, revision T.

The chips on them mostly do not have markings, this one was a small
one in the middle of the motherboard.

I really like the drives, their simplicity, cost and support from
AMC. I do not know if I can guess the cause. But, possibly,
interference again is to blame.

VERY unlikely.

Agree.


You mentioned ferrite cores to place on these cables. Would you
suggest any particular Digikey part number?

Sorry, I really don't have a part number. You might check old computer
cables for those
bulges in them, those are big ferrite rings for noise isolation. You
want to run both
motor cables through the same core, so they are not exposed to the motor
current
(the current in the two wires cancels out).

The split-sleeve emi-filter chokes are what Iggy seeks. Here is an
example:

http://search.digikey.com/scripts/Dk...me=240-2131-ND



However, these chokes really are not that effective compared to real
shielding.
I would first shield the motor power leads, as they are very high power.

Joe, I bought those rings. I will shield the wires going to the big
terminal block from the drives, (and ground the shield) and would put
the rings on the wires going out of the terminal block to the motors.

Cheap enough to just try. One normally puts all three (or four) motor leads
through the same core, so the power-frequency magnetic fields largely cancel, to
avoid magnetic saturation of the ferrite. One can put multiple cores on the
same cable, one after another. Nor will anything bad or permanent happen if you
do put a single wire through a core, perhaps saturating the ferrite, so there is
no reason not to try everything.

I will put them on tonight.

i

What diameter of wire hole ? - need any ribbon ones - have them.
I think I have several like you mention from industrial equipment use.

I have a 3 phase, 50 amp RF line filter that I ran out of room to use.
Have AT NIC and modern NIC , various SIMS. e.g. HP printers and old pc's.

Let me know. Should be easy to get my hands on them.

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
"Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Originator & Charter Founder
IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com/

On 9/3/2010 10:22 AM, Ignoramus24760 wrote:
On 2010-08-30, Joseph wrote:
In articleYuOdnSLQTJ6Q2ObRnZ2dnUVZ_sqdnZ2d@giganews. com,
Jon wrote:

Ignoramus5734 wrote:
That was am AMC 30A8 amplifier, revision T.

The chips on them mostly do not have markings, this one was a small
one in the middle of the motherboard.

I really like the drives, their simplicity, cost and support from
AMC. I do not know if I can guess the cause. But, possibly,
interference again is to blame.

VERY unlikely.

Agree.


You mentioned ferrite cores to place on these cables. Would you
suggest any particular Digikey part number?

Sorry, I really don't have a part number. You might check old computer
cables for those
bulges in them, those are big ferrite rings for noise isolation. You
want to run both
motor cables through the same core, so they are not exposed to the motor
current
(the current in the two wires cancels out).

The split-sleeve emi-filter chokes are what Iggy seeks. Here is an example:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=240-2131-ND


However, these chokes really are not that effective compared to real shielding.
I would first shield the motor power leads, as they are very high power.

Joe, I bought those rings. I will shield the wires going to the big
terminal block from the drives, (and ground the shield) and would put
the rings on the wires going out of the terminal block to the motors.

i