1. I sold some parts of this Bridgeport CNC mill, specifically the
Heidenhain controller and an optional keypad for same. After
subtracting the sold price from the price I paid for the whole mill,
the cost of the mill dropped down to $133.

2. I spent about an hour yesterday looking into the control cabinet,
the one with wires and relays, not the one housing the CNC computer. I
have gotten to the point of better understanding of some aspects of
wiring.

I was first glad to note that my phase converter is relatively
balanced and outputs 235 and 246 volts depending on legs.

There is a strange relay that powers up the main transformer, that was
not obvious to figure out, so I had to push the contacts of it with a
screwdriver.

I found, specifically:

a) The main transformer is shaped like digit 8 and seems to take
single phase only. It is labeled as 3 kVa. I am very tentative on
declaring this a 1 phase transformer, but this is what it looks like,
as I found only two inputs with voltage of 235 volts between them.
The transformer seems to output several voltages, but one of them is
380 volts.

b) The servo drives are Bosch Z15-1-240v. Despite "240v", the drives
are connected to the transformer's 380v output. I searched Google on
this and found a lot of desperate people looking for schematic, no
schematic, and a lot of web spammers advertising "repair" of these
drives.

c) The drives seem to have 380v as power in, have control inputs from
the controller setting speed, and what seems to be tachometer
input. (as I said yesterday, the motors definitely have tachometers on
them).

d) There is three more wire coming out of the servo drives, that seem
like they would probably be used to drive motors. I am not sure why
three and I am not sure whether I can figure it out reliably (thoigh
maybe I can).

Therefore, I have two choices:

Choice #1: just sell those Bosch drives, which seem like they could
fetch some reasonable amount of $$$ like $300, and follow the original
advice of Karl and install the AMC drives that I purchased on Karl's
recommendation. I will try to test the AMC drives prior to removing
Bosch drives.

Choice #2: Leave Bosch drives plugged in, leave their connection to
servos as is, and hook them up to Jon's PPMC. The attraction of choice
#2 is that it is superficially easier. However, I do not see the
inhibit function on the drives that could be triggered by limit
switches, and thus I think that they are not as safe to use. I would
have to program inhibit functionality in software, which is obviously
less idiot proof than having drives that are unable to overrun the
limit switches. Also, I believe that I may need three phase to run the
mill, which is something that I hope to avoid.

I will sit on it for a couple of days.

My plan for this weekend is to figure out the power wiring of the
servos. (what goes into the power connection box, how everything is
connected and numbered). Also to reinstall the mill's head.

i

Brian, thanks for the warning. I already hooked it up to the
converter, so if there was any damage, it may have already occurred. I
think that I was lucky and voltage from lines L1-L2 was applied to the
transformer and such.

i

Ignoramus28478 wrote:

Brian, thanks for the warning. I already hooked it up to the
converter, so if there was any damage, it may have already occurred. I
think that I was lucky and voltage from lines L1-L2 was applied to the
transformer and such.

i

Okay, I think you got it. Two phases are attached to the generated leg. You do not want
the control power transformer on those. Stick to the line connected leg.

Wes

On 2010-06-11, Wes wrote:
Ignoramus28478 wrote:

Brian, thanks for the warning. I already hooked it up to the
converter, so if there was any damage, it may have already occurred. I
think that I was lucky and voltage from lines L1-L2 was applied to the
transformer and such.

i

Okay, I think you got it. Two phases are attached to the generated leg. You do not want
the control power transformer on those. Stick to the line connected leg.

Exactly. I traced some wires last night, it does look like the servo
stuff is using lines L1-L2 and L3 goes to the spindle motor only.

In my 3 phase wiring, I made really sure that L1-L2 are where they
belong.

i

Ignoramus28478 wrote:

On 2010-06-11, Wes wrote:
Ignoramus28478 wrote:

Brian, thanks for the warning. I already hooked it up to the
converter, so if there was any damage, it may have already occurred. I
think that I was lucky and voltage from lines L1-L2 was applied to the
transformer and such.

i

Okay, I think you got it. Two phases are attached to the generated leg. You do not want
the control power transformer on those. Stick to the line connected leg.

Exactly. I traced some wires last night, it does look like the servo
stuff is using lines L1-L2 and L3 goes to the spindle motor only.

In my 3 phase wiring, I made really sure that L1-L2 are where they
belong.

i

Excellent. I hope your son is by your side during this, subject to the attention span of
small boys. Watching is part of learning, especially if your son asks good questions and
you are willing to stop and explain.

Obviously he can't advise you but when he makes connections using your explanations of
what you are doing or trying to understand, a bit of praise for getting a grip on it or
asking the right follow up questions is positive reinforcement to encourage a life of
learning.

I have a strong feeling you are a dad he wants to emulate.

Wes

--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller

O.K. That voltage is probably necessary to get full torque at
full speed from the servo motors you have. (There should be maximum
voltage and maximum current on the motor's labels.)

Yep, max voltage 145 volts, pulse amps 32. (wow)

See

http://igor.chudov.com/misc/ebay/tmp/tmp-7331.jpg

You can run them on lower voltages, but as a result you will get
less maximum speed and less torque.

I think the servos you bought are 80 volt. You may (probably) be fine if you
go the AMC route.

I'd suggest your son do a speed and acceleration test to help you decide.
this would be fun. Take a 2:1 transformer, a bridge rectifier, and a
electrolytic cap if you have it. Show him how this makes AC into DC. Have
him read a web site on design of these. (Today's reading English lesson) Now
hook it to your X axis with the table at center travel. Bump your power to
it for a second and measure acceleration and velocity. if your transformer
has 4:1 reduction, do that one too. If you need more speed, make a run with
110 to the rectifier. Extra credit, use a variac in the circuit.

If you make a point of doing these lab exercises at every opportunity,
you'll have a friend for life.

Now, decide if 80 volt is enough. If it isn't and you want to go the AMC
route, there are several amps that will work. they tend to go in the $50-$80
range.

Karl

On 2010-06-11, Karl Townsend wrote:

O.K. That voltage is probably necessary to get full torque at
full speed from the servo motors you have. (There should be maximum
voltage and maximum current on the motor's labels.)

Yep, max voltage 145 volts, pulse amps 32. (wow)

See

http://igor.chudov.com/misc/ebay/tmp/tmp-7331.jpg

You can run them on lower voltages, but as a result you will get
less maximum speed and less torque.

I think the servos you bought are 80 volt. You may (probably) be fine if you
go the AMC route.

I'd suggest your son do a speed and acceleration test to help you decide.
this would be fun. Take a 2:1 transformer, a bridge rectifier, and a
electrolytic cap if you have it. Show him how this makes AC into DC. Have
him read a web site on design of these. (Today's reading English lesson) Now
hook it to your X axis with the table at center travel. Bump your power to
it for a second and measure acceleration and velocity. if your transformer
has 4:1 reduction, do that one too. If you need more speed, make a run with
110 to the rectifier. Extra credit, use a variac in the circuit.

If you make a point of doing these lab exercises at every opportunity,
you'll have a friend for life.

Now, decide if 80 volt is enough. If it isn't and you want to go the AMC
route, there are several amps that will work. they tend to go in the $50-$80
range.

Karl, I do not really need to set speed records on this mill. Since it
is not enclosed, the faster it goes, the more dangerous it is to any
living being who would be unlucky enough to be close to it. (many
obvious safety warnings apply etc)

I figured out some servo wiring (see my more recent post) and ran the
Y axis servo motor. I checked out the speed at 30 volts with a little
power supply I had. I think that it was almost adequate. So 80 volts
is not a problem.

The question that is on my mind right now, is that perhaps I should
simply keep everything that is in the cabinet -- all the safety
wiring, relays, etc, with new encoders, and hook up EMC/PPMC to that
just as Heidenhain was. The plus is I keep all the safety features
that seem to be provided by all those relays.

Of course, I could only do it if I figure out the basics of their
wiring.

"Ignoramus10537" wrote in message
...
On 2010-06-11, Karl Townsend wrote:

O.K. That voltage is probably necessary to get full torque at
full speed from the servo motors you have. (There should be maximum
voltage and maximum current on the motor's labels.)

Yep, max voltage 145 volts, pulse amps 32. (wow)

See

http://igor.chudov.com/misc/ebay/tmp/tmp-7331.jpg

You can run them on lower voltages, but as a result you will get
less maximum speed and less torque.

I think the servos you bought are 80 volt. You may (probably) be fine if
you
go the AMC route.

I'd suggest your son do a speed and acceleration test to help you decide.
this would be fun. Take a 2:1 transformer, a bridge rectifier, and a
electrolytic cap if you have it. Show him how this makes AC into DC. Have
him read a web site on design of these. (Today's reading English lesson)
Now
hook it to your X axis with the table at center travel. Bump your power
to
it for a second and measure acceleration and velocity. if your
transformer
has 4:1 reduction, do that one too. If you need more speed, make a run
with
110 to the rectifier. Extra credit, use a variac in the circuit.

If you make a point of doing these lab exercises at every opportunity,
you'll have a friend for life.

Now, decide if 80 volt is enough. If it isn't and you want to go the AMC
route, there are several amps that will work. they tend to go in the
$50-$80
range.

Karl, I do not really need to set speed records on this mill. Since it
is not enclosed, the faster it goes, the more dangerous it is to any
living being who would be unlucky enough to be close to it. (many
obvious safety warnings apply etc)

I figured out some servo wiring (see my more recent post) and ran the
Y axis servo motor. I checked out the speed at 30 volts with a little
power supply I had. I think that it was almost adequate. So 80 volts
is not a problem.

The question that is on my mind right now, is that perhaps I should
simply keep everything that is in the cabinet -- all the safety
wiring, relays, etc, with new encoders, and hook up EMC/PPMC to that
just as Heidenhain was. The plus is I keep all the safety features
that seem to be provided by all those relays.

Of course, I could only do it if I figure out the basics of their
wiring.

I would suggest you rip it out if you plan to keep the machine long term.
Stuff breaks at the least opportune times. Keeping obsolete equipment is
just asking for future trouble. Just my 2 cents.

Karl

On 2010-06-11, Karl Townsend wrote:

"Ignoramus10537" wrote in message
...
On 2010-06-11, Karl Townsend wrote:

O.K. That voltage is probably necessary to get full torque at
full speed from the servo motors you have. (There should be maximum
voltage and maximum current on the motor's labels.)

Yep, max voltage 145 volts, pulse amps 32. (wow)

See

http://igor.chudov.com/misc/ebay/tmp/tmp-7331.jpg

You can run them on lower voltages, but as a result you will get
less maximum speed and less torque.

I think the servos you bought are 80 volt. You may (probably) be fine if
you
go the AMC route.

I'd suggest your son do a speed and acceleration test to help you decide.
this would be fun. Take a 2:1 transformer, a bridge rectifier, and a
electrolytic cap if you have it. Show him how this makes AC into DC. Have
him read a web site on design of these. (Today's reading English lesson)
Now
hook it to your X axis with the table at center travel. Bump your power
to
it for a second and measure acceleration and velocity. if your
transformer
has 4:1 reduction, do that one too. If you need more speed, make a run
with
110 to the rectifier. Extra credit, use a variac in the circuit.

If you make a point of doing these lab exercises at every opportunity,
you'll have a friend for life.

Now, decide if 80 volt is enough. If it isn't and you want to go the AMC
route, there are several amps that will work. they tend to go in the
$50-$80
range.

Karl, I do not really need to set speed records on this mill. Since it
is not enclosed, the faster it goes, the more dangerous it is to any
living being who would be unlucky enough to be close to it. (many
obvious safety warnings apply etc)

I figured out some servo wiring (see my more recent post) and ran the
Y axis servo motor. I checked out the speed at 30 volts with a little
power supply I had. I think that it was almost adequate. So 80 volts
is not a problem.

The question that is on my mind right now, is that perhaps I should
simply keep everything that is in the cabinet -- all the safety
wiring, relays, etc, with new encoders, and hook up EMC/PPMC to that
just as Heidenhain was. The plus is I keep all the safety features
that seem to be provided by all those relays.

Of course, I could only do it if I figure out the basics of their
wiring.

I would suggest you rip it out if you plan to keep the machine long term.
Stuff breaks at the least opportune times. Keeping obsolete equipment is
just asking for future trouble. Just my 2 cents.

Karl, would you say the same thing about all those safety relays and
such? Just rip out everything and redo everything? Or just the amps?

I am sorry for being a little redundant. I want to make sure that I do
not do anything rash and stupid.

i

Karl, would you say the same thing about all those safety relays and
such? Just rip out everything and redo everything? Or just the amps?

I am sorry for being a little redundant. I want to make sure that I do
not do anything rash and stupid.


If you don't want to do anything stupid, then don't do anything at all!

I'm an empty box guy. Rip it all out. Inspect components to see if you want
to re use. Wire number all the wires going out to sensors and devices. Keep
a spread sheet of wire number and function (way quicker that doing a EE
drawing) All wires go between two devices, so I keep device 1, pin#, device
2, pin#, wire number, color, voltage, function on each line. All my 24 volt
dc is blue, my 5 volt red, my 10 volt orange, common white. I keep all the
AC completely separate and use red, yellow, back for hot, white common,
green ground.

Start building your machine and maintain that spreadsheet. When I'm done the
machine is duck easy for future maintenance. And, The time I waste by
putting the same components back in is more than saved with good docs and a
better layout in the cabinet.

Karl

On 2010-06-11, Ignoramus28478 wrote:
On 2010-06-10, DoN. Nichols wrote:
On 2010-06-10, Ignoramus28478 wrote:

[ ... ]

I found, specifically:

a) The main transformer is shaped like digit 8 and seems to take
single phase only.

Hmm ... let me try a couple of ASCII drawings to see which it is
closer to (the usual advice for Courier or another fixed pitch font
applies. I know that you know to use it, but in case someone else is
reading this it may help them)

[ ... ]

IIRC mine looks different.

.-------+-------.
| oooo|oooo |
| oooo|oooo |
| oooo|oooo |
| oooo|oooo |
| oooo|oooo |
.-------+-------.

The picture is on the bottom left he

http://igor.chudov.com/misc/ebay/tmp/tmp-7343.jpg.html

O.K. Standard single phase transformer. Probably most of those
taps are to allow it to be configured for different line voltage inputs
-- probably 240 V up to well over 480V -- 5??V perhaps

And it may feed that voltage from a single phase to all of the
electronics in that rack. I note that each servo amplifier appears to
be fed by its own transformer (above it) which otherwise do not have
enough terminals to allow line voltage tweaking here. So it looks as
though your entire three axes are run from a single phase -- making it
easier to re-wire to use that in place of the original three phase.

and it confirms what I am saying.

Single phase for sure.



Both have a lot more winding and a lot less open window than I
showed, but I made it this open to make it clear how it is set up. The
ferro-resonant has another winding (on the primary side IIRC) which is
connected to an oil-filled AC capacitor and nothing else.

This one, seems to be one phase transformer.

Yes. Nothing special. I'm not even sure why you commented on
the shape -- it is a standard transformer core. I was expecting
something different.

It is labeled as 3 kVa. I am very tentative on
declaring this a 1 phase transformer, but this is what it looks like,
as I found only two inputs with voltage of 235 volts between them.
The transformer seems to output several voltages, but one of them is
380 volts.

Any photos?

http://igor.chudov.com/misc/ebay/tmp/tmp-7343.jpg.html

Single phase.

b) The servo drives are Bosch Z15-1-240v. Despite "240v", the drives
are connected to the transformer's 380v output. I searched Google on
this and found a lot of desperate people looking for schematic, no
schematic, and a lot of web spammers advertising "repair" of these
drives.

Hmm ... any useful markings on the drivers? Terminal strips
marked for function? Trimmer pots used for zeroing balance and tuning
gain for both input and feedback and for adjusting damping.

Hard to see without removing them, I will try.

It looks as though each servo amp has its own small transformer
on the board -- probably to isolate the on-board circuits from the
controlled voltage and current.

No photos of the servo amp boards from an angle which will show
much of the components -- I can't even tell whether there are trimpots
within reach of the front edge.

The board on the door (or side wall?) appears to be the serial
interface board -- which is likely to be set up to support either RS-232
or 20mA current loop.

c) The drives seem to have 380v as power in, have control inputs from
the controller setting speed, and what seems to be tachometer
input. (as I said yesterday, the motors definitely have tachometers on
them).

O.K. That voltage is probably necessary to get full torque at
full speed from the servo motors you have. (There should be maximum
voltage and maximum current on the motor's labels.)

Yep, max voltage 145 volts, pulse amps 32. (wow)

Yep -- the servo amp must be tuned to never exceed that 32A
limit. You have 9.5 V/1000 RPM and 2500 RPM max, so a maximum of 27.75
V from the tach at max speed.

See

http://igor.chudov.com/misc/ebay/tmp/tmp-7331.jpg

You can run them on lower voltages, but as a result you will get
less maximum speed and less torque.

d) There is three more wire coming out of the servo drives, that seem
like they would probably be used to drive motors. I am not sure why
three and I am not sure whether I can figure it out reliably (thoigh
maybe I can).

Those could be for inhibiting motion on the two directions, a
common, and a separate inhibit for each direction.

I will check, I think that they are for power. I can find it out by
tracing wires.

O.K. Please do so. :-) If they are power, they probably go to
the transformers mounted just above them.

[ ... ]

At least on the function of the wires and where the trimpots are for
different functions? If so, I would suggest trying to use them
first -- since they are a proper match for the supply voltages
needed for the motors. Not sure whether your AMC drives are for
that high a voltage.

Not even close, 80v as opposed to 145.

So -- the question is whether you can sacrifice the maximum speed
and torque combination for your uses.

Choice #2: Leave Bosch drives plugged in, leave their connection to
servos as is, and hook them up to Jon's PPMC. The attraction of choice
#2 is that it is superficially easier. However, I do not see the
inhibit function on the drives that could be triggered by limit
switches,

What about those unidentified three wires?

I should try to make them identified.

I'll look forward to that.

Good Luck,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

On 2010-06-11, Karl Townsend wrote:

O.K. That voltage is probably necessary to get full torque at
full speed from the servo motors you have. (There should be maximum
voltage and maximum current on the motor's labels.)

Yep, max voltage 145 volts, pulse amps 32. (wow)

[ ... ]

I'd suggest your son do a speed and acceleration test to help you decide.

Consider that a certain percentage of CNC milling is rapid moves
-- moving to cut on another edge, or moving clear to change the tool --
and here is where the maximum speed helps you most. Seldom are cuts
actually made at those speeds. (And the rapid moves are also where
servos are a major win over steppers. :-)

this would be fun. Take a 2:1 transformer, a bridge rectifier, and a
electrolytic cap if you have it. Show him how this makes AC into DC. Have
him read a web site on design of these. (Today's reading English lesson) Now
hook it to your X axis with the table at center travel. Bump your power to
it for a second and measure acceleration and velocity. if your transformer
has 4:1 reduction, do that one too. If you need more speed, make a run with
110 to the rectifier. Extra credit, use a variac in the circuit.

One thing worth doing at the same time (or at last once you are
setting up the servo amps if you use other than what is already tuned
for it) is to hook an oscilloscope to the tach output voltage, then feed
a low frequency square wave (perhaps 10 Hz or so) into the command input
to the servo amp (make sure that the square wave goes equally above and
below ground so it will move back and forth around a center point
instead of driving to one end and hitting the stop), and look for proper
damping of the tach output. If it overshoots, you will likely have
hunting with physical overshoot and motion back. If it moves up with a
very rounded leading edge, then your motor will lag far behind the
commanded position. With just the right amount of damping, it will be a
fairly vertical leading edge, a tiny amount of rounding at the corner
and then a flat top. (Very much like tuning an oscilloscope probe to
the input capacitance of the scope using the 1 KHz square wave.)

This tuning should be with the motor driving the table, and a
typical load on the table -- milling vise and something on the large
side of what fits in the vise -- and compare the change when you empty
the vise -- and when you remove the vise and work with a bare table
(sort of like a single plate of aluminum held down with workpiece
clamping sets. :-)

The servo amps which I have include places to plug in extra
capacitors to tune the damping close, and trimpots to fine tune it.
(They also have a built-in transformer and power supply to run from 120
VAC.

O.K. Saving the image of the transformer then zooming in on a
servo amp shows two gray multi-turn trimpots visible. There really
should be more -- I guess accessed via the top or bottom edge instead of
the front edge.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

Ignoramus28478 wrote:
c) The drives seem to have 380v as power in, have control inputs from
the controller setting speed, and what seems to be tachometer
input. (as I said yesterday, the motors definitely have tachometers on
them).


Sounds a little high, 380 V into a rectifier-filter will give ~ 537 V
DC. I suppose if this is a center-tapped
winding, then they could get 270 V, which sounds more reasonable.
d) There is three more wire coming out of the servo drives, that seem
like they would probably be used to drive motors. I am not sure why
three and I am not sure whether I can figure it out reliably (thoigh
maybe I can).

It is very common for the end limit switches to be fed to the servo amp,
to disable the amp to drive toward a tripped limit switch.
This could take 3 wires (common or + 15 V, and the two limit switch
contacts). These would often be set up for an NC switch, so a dirty
contact ot broken wire would disable the amp in a fail-safe manner.
Then, there's the velocity command signal, two wires.
Therefore, I have two choices:

Choice #1: just sell those Bosch drives, which seem like they could
fetch some reasonable amount of $$$ like $300, and follow the original
advice of Karl and install the AMC drives that I purchased on Karl's
recommendation. I will try to test the AMC drives prior to removing
Bosch drives.

Choice #2: Leave Bosch drives plugged in, leave their connection to
servos as is, and hook them up to Jon's PPMC. The attraction of choice
#2 is that it is superficially easier. However, I do not see the
inhibit function on the drives that could be triggered by limit
switches, and thus I think that they are not as safe to use. I would
have to program inhibit functionality in software, which is obviously
less idiot proof than having drives that are unable to overrun the
limit switches. Also, I believe that I may need three phase to run the
mill, which is something that I hope to avoid.

Just make sure you have some system to E-stop the drives. Either
inhibit them or kill the power input with a relay.
The limit switch = inhibit likely runs through some part of the CNC
control, which you have pulled out.

Jon