Strippit  FC1000/3  Machine
Problems  &  Fixes

All  FC1000/3  HECC80  Machines used the  G.E.  Model 3  or  Improved Model 3A  Servo Drives. 
These Servos were not widely used in the Industry,  can be hard to repair,  and Parts are somewhat Expensive & Hard to get.    Its Best to do everything you can do to Avoid Servo Problems!
There are More Pictures and Discussion of these Servos on My   2   Servo Web-Pages.    Read Them!

These Machines & Servo Drives are actually fairly reliable,  but they are all  30+ years old now,
and Should have Regular Maintenance,  and I would Even  "Baby"  them a little to Minimize Problems.
However,  The Typical Shop Gives Them  Zero Maintenance,  and Is Surprised when they Finally Fail.

Typical Failures are   Red  LED-Lights On  in the Servo Cabinet which means  Over-Current,  and
CRT-Display will show a  "Servo Down"  Message.     This is usually caused by  
Burned-Out  Servo-Motor,  and/or  Blown Power-Modules,   and/or  Blown  PWMC7  &  PWMC8 
Servo Control Boards,  and/or  Shorted Wiring  between Servo-Drive and Servo-Motor.

Blown Power-Modules  Can  Blow  The Servo-Control Boards,
Blown Servo-Control Boards  Can  Blow  The Power-Modules!

You have to Replace  All  Bad  Modules  &  Boards  &  Motors at The Same Time,
Or You Risk Blowing Them Again The First Time You Put Power On To Machine!

To Minimize Servo-Drive Problems,  Do  ALL Of The Following!!!

1  ---  Incoming  AC Voltage to Machine is the Most Important Factors of Servo Reliability. Because of the 2-Speed Press Drive Motor,  FC1000/3 Machines are all Single-Voltage Machines.
That is,  they are Wired for  230 Volts AC,   OR  are Wired for  460 Volts AC,   and can Not be changed.
Your Machine's voltage is Stamped on  Metal-ID Plate on  back-side of the Machine. 

High  AC-Voltage Causes  High DC Servo-Buss Voltage
which is the  Major Cause of Servo Drive Failures!!!

  I Recommend that Machines Wired for 230 Volts  have the
  incoming voltage at  220 to  230 Maximum!!!

  I Recommend that Machines Wired for 460 Volts  have the
  incoming voltage at  440 to  460 Maximum!!!

If your Voltage is Higher,  Reduce it!   Get Power Company  to Change Transformer-Taps on your Power Poles Outside.   Some Shops also have their Own Inside/Outside Transformers for the whole building,  have your Electrician or Power Company Change the Taps in it if Necessary. 

And finally,  you can add  Boost-Buck Transformers  on Machine itself to  Reduce  or  Raise Machine Voltage,  or you can  Add Smaller  Boost-Buck Transformers  to Adjust just the  Servo-Drive Voltage.
These Transformers typically can be Wired to Raise or Reduce Voltage  12,  24,  36,  or  44 Volts.
Interesting enough,  this can be done with  2  or  3  Transformers.   These are made by many Manufactures like   McMaster-Carr,   Grainger,   Acme,   Sola,   G.E.,   Federal-Pacfic,   and others.  Consult Transformer Manufacturer and a Good Industrial Electrician for more information on
Model Selection & Installation.
The Last Machine I Installed,  I added  2 Acme Buck-Transformers to Servos,  and it only cost  $600.

No Excuses,  Just Get It Done Right!  
The Following are 3 Examples of how we added
Boost-Buck Transformers to get the Correct Servo Voltages.

4  ---  Slow-Down  the   X & Y  Axis Speed!

FC1000/3  Machines are Very Fast at Up to  3000 Inches per minute, 
but the Axis are usually Accelerating or Decelerating Hard from this Speed, 
which  Greatly Stresses the  Servo-Motors,  Servo-Drives,  Bearings,  and  Ballscrews. 

Slowing-Down  Speed  will Greatly Reduce  Wear  &  Failure of these Expensive items!

The Best way to do this is to Simply Insert a     F2     Command in  ALL  Of  Your  Part-Programs
on the  Line of Code  where you make your  First    X Y  Move  &  Turn-On the Punch.

N001   G69                                                           Home  X, Y, and T  Axis
N002   X48.          Y38.         M75                       Go to  Load Position  and  Stop
N003   X22.345   Y19.739  T02  G68   F2       The First Punch Line,   F2   Limits  Axis Speed to  2000 IPM

Note!   Surprisingly,  the  F2  does NOT lengthen your Run-Time very much,  as axis are not at  3000
IPM Speed very much.    But  Reducing the  Hard  Acceleration  &  Deceleration Greatly Improves Reliability,   Accuracy,  and  Reduces some  Punching  and  Part-Holding Problems. 
And It Costs You Nothing!    Add  F2  to  Al l Part Programs!  Some shops use  F15  to go Even Slower.

5  ---  Service the Servo-Motors.   Bad Motors can Blow Servo-Modules & Servo-Boards!

        ---  Carbon-Dust builds-Up inside the Motors and Arcs.
              Take  Brush-Covers off  and  Blow-Out the Dust regularity.

       ---  Examine the Brushes.    Replace if Worn-Down.    Careful,  These are  Very Tricky to Check! 
             If you Lose a Spring or Screw,  it will get Pulled-Into Motor,  and it will have to be
             Disassembled & Repaired by a  Professional  (NOT by Local Motor Shop  "Down the Street" ) !

       ---  Check Brush Retaining Springs,  Replace if they seem Weak or are Burnt.

       ---  Make sure Motors have Strong Cooling Air-Flow out of Motor. 
             Air-Blowers can Fail,   Filters get Clogged,   Air-Hoses can Rot-Out.    Repair as necessary.

       ---  Check Tachometer Ohms.    A good Tach Armature with a Clean Commutator, 
             good Tach-Brushes,  Tach-Springs that are not Bent-Up,   will read about  65  to  80  Ohms. 
             If much over  100 Ohms,  something is Wrong.    Have it Fixed!

       ---  Watch  Brushes  &  Commutator  while making  30 Inch-Moves at  Full  3000 IPM Speed.
             If There Is  Strong  Arcing  &  Popping,   Motor Armature  Probably Has  Shorted-Windings.
             Motor Needs to Be  Replaced  or  Re-Wound  &  Re-Built  Before It  Blows-Up Servo-Drive!

       ---  Most Servo Motors Fail from Overheating. 
             Your Operator Jammed a  Punch-Down,  or  Slug Popped-up,  or  Sheet Jammed Up.
             Machine's Axis tries to Move,  but it can't from the Jam-Up,  so you are in a Stalled-Motor
            Condition which Draws  Full-Power  from Servo and will  Cook the Motor in Just a Minute
            or 2  if he does Not Shut it Off!     Operator will also Forget to tell you this Happened!

            Motor Windings then get so Hot that Insulation Melts & Breaks-Down,  then Electricity Shorts
            from Winding to Winding,  Pulling Too Much Current,  and will Trip a Servo Over-Current Fault,
            or even Blow the Servo Drive.   You Can NOT Check for this with a Ohm-Meter or Megger!

            It is Hard to tell a Bad  Burn-Armature Motor out in the Customers Shop. 
            The Best way to tell is to replace with a Known Good Motor. 

            However,  I have Developed the following way to Quick-Test a Motor in the Field,
                                     Though This Will Not Find All Faults!
            You will need a small Variable Voltage Laboratory Power Supply with Build-in Voltmeter
            and Current Meters.    I use this Model that puts out up to  40 Volts DC at up to  3 Amps.

This page was last updated: May 30, 2022

This is the  #17546-000 
Resolver Feedback Package.

Why Pay Strippit  3  Times our Price
for  The Same Part?
  Where to Buy It is Kind of a
No-Brainer,   Don't You Think?

  Update.   Strippit does Not even have Feedback Packages Anymore!
We have  Lots of them!

  And Don't Forget the
#17648-000  Resolver Coupling.
  Couplings are Often Broken
by  Bad Resolvers.

11 ---  Make sure a  8 Foot Ground Rod was put-in  All-The-Way  into The Ground!
          And is firmly attached to the Ground Strap hanging under  Machine's Control Cabinet.

12 ---  Many FC1000/3 Machines have been Moved and were Never Properly Reinstalled.
          If not properly installed,  there is excessive Vibration which I have seen shake Transistors
          right off a Servo board!    Excess Vibration can & will cause many Control & Servo Failures!

          --  The  Machine Must be Level,  with equal Pressure on all  6 Barry-Mount  Rubber Feet.
          --  The  4 Shipping Bolts in Servo Cabinet,  and  4 Bolts in Control Cabinet must be Removed.
          --  The  Bolts on the  Cross-Bar  between  Cabinets must be Removed.
          --  The  Feet under the  2  Cabinets must be Lowered to the Lift Cabinets a bit,
               so  Cabinets  "Float"  on the Rubber Mounts attached to Machine Frame.

For Hi-Tonnage Punching,  there is a Much Better way to Mount the Machine using  "Jake Bolts"
and  Epoxie Machine Grout,  which is how Strippit Mounts Machines now to Reduce
Shock & Vibration,  and Improve Machine Reliability.    We can provide details if needed.

Note,   There is More Information on Proper Machine Installation
on Our   "Bubble Memory Problems"   Web-Page.

13 ---  Test that the  X & Y  Slow-Down  and  Limit Switches  are Working Properly.  

These Switches Protect Machine Mechanical Parts and  Electronic Servo Drives from Damage by
Preventing Hard  "Crashes" at the End of an Axis's Travel.    As an Axis approaches it's End of Travel
in the High-Speed Mode,  it should Engage  "Slow-Down"  Switch or Sensor forcing Axis to Shift
to  "Slow"  Mode.    If you Persist in Moving Axis toward  End of Travel,  you should next Engage
"Limit"  Switch or Sensor,  which should Generate an  "All Hold"  Condition and
Shut-Down the Servo Drives,  and  Axis should Stop a Couple of Inches before it would have Hit Something at the End of it's Travel.    Check this every 6 Months,  for  Both Directions in
Both  X and Y Axis.    Promptly  Repair any Problems found.

14 ---  Tune the Servo Drives a Little  "Softer"  with a  Little Less Gain.    This causes Servo-Drives
and Servo-Motors to Require Less Current,  with the Result that they Fail Less and Last Longer.

Most Strippit Manuals and my Old Servo Manual say to set  X & Y  Following-Error to about  330 usec. when making  30 inch moves.    I Now  Set  X & Y  Following-Error to about  380  to  400 usec.  when making  30 inch Moves.     This requires a Oscilloscope and a Technician that knows what he's doing.

I set  T-Axis Following-Error at  380  to  400 usec.  while  Homing the Turret Axis.

I usually have  "Max Speed"  Pot on  PWMC Boards turned  All the way Down for  Minimum-Gain.
  Note!   The  Adjustment Direction  on This Pot  is  Counter-Intuitive,
as you have to  Turn Pot  Clockwise  to  Reduce the Gain!    
I  Usually Turn  Max Speed    Pot  All The Way  Clockwise    and   Leave It There!

15 ---  Make sure Fan at Bottom of the Servo Drive Units is Running,  and is Blowing Air Up through
Aluminum Heat Sinks!    These Fan Motors Seize-Up in old age.    We Stock Replacements!

16 ---  Tooling is Critical!
Dull Punches & Dies,   Wrong Die Clearances,   Miss-Adjusted Holders,  and Just Plain  Worn-Out Tooling will Cause  Stuck-Punches,  Failure to Strip,  and  Slug Pop-Ups  that will Not Only Ruin your
Part-Sheets,  But will Also Tear Up the Mechanical Parts on your Machine,  and can Blow-Up Servo Drives Electronics when Axis are Jammed!    Junk-Tooling  Will Not Work In a  HI-Speed Punch Press!

Caution!        Caution!        Caution!

Do NOT Ever Reach-In,   Get On-Machine To Lube,
Move Workclamps,  Or  Work On The Machine For Any Reason,
With The  Machine  On!!!

Always Turn  The-Control  Off!!!

If a  Control  or  Machine Failure Should Occur,
Axis Could  "Run Away"  And Cause  Injury  Or  Death!!!
7  ---  Electronics Do  NOT  Like  Heat  or  Cold!

          Strippit  Air-Conditioned  CNC Control-Cabinet,   But Not the Servo-Cabinet!    I Would Seal-Up
          Servo-Cabinet,  and  Mount a  4000 BTU  Control-Cabinet  Air-Conditioner,  from  Kooltronics
          or  McLean  Co's.,   to The Swing-Out  Servo-Cabinet  Door!

         These are Special Air-Conditioners that are Made to Easily Mount onto CNC Machine Cabinets,
         recirculates the Air to Keep Out Humidity and Dirt,  and will Not Spray Water into Cabinet.
         Do Not Even Think about trying to adapt a cheap Window Air Conditioner to Servo-Cabinet!
         Maintain Servo-Cabinet  Air Temperature at  70  to  75  Degrees Fahrenheit.

         Also make sure  Control-Cabinet Air Conditioner  is Keeping CNC Control at  70  to 75 Degrees.

       Electronics Do NOT Like Cold!
         Many Shops in the North Turn-Off Heat at Night in the Winter.   The next Morning Shop may be
         as cold as  30 or  40  Degrees Fahrenheit!   CNC Controls are  Industrial Grade Electronics,
         Not  Military or  Aero-Space Electronics,  and they  Will Not Reliably Work Below  50 Degrees!
         I often see  Power Supplies Fail,  Bubble-Boards Lose  Memory-Data,  Servo-Drives Blow-Up,
         and  Oils & Greases in Machine Too Thick to Flow Correctly!    This is for  All  Machines,
         Not just Strippits!    Do  NOT Turn-On your Machines Until it has Warmed Up to  50+  Degrees!

8  ---  Capacitors go Bad with Age,  and can cause Servo-Drives Failures.
           We not only replace Bad Capacitors,  but also Up-Size certain Capacitors for Greater Reliability.
          The  PWMC7  &  PWMC8  boards Should be sent-in to us,  and we can
          Up-Date them with only 2 day Turn-Around Repair time.  

         The  PSRG3  or  PSRG5  Power Supply board  should also be Updated
          with New Caps.,  and we can also  Retrofit a Better  MVR-Relay to Improve Reliability,
          and  Add a LED-Indicator Light to Signal when the Relay is  Pulled-In or Not,
          which greatly helps in Troubleshooting Servo  On & Off  Problems.

9  ---  Make sure Ballscrews & Guide-Bars are Clean, Well Oiled, and in Good Condition.
           A Bad or Worn Ballscrew or Guide-Bearings can add a lot of Mechanical Drag on the
          Servo-Drive which can Stress & Fail them.

          Also,  The Axis Lube System Does Not Work On Many FC1000/3 Machines because of a
          Control Software Bug,  and  Failures in the Lube-Drive Hardware.    Do NOT Depend On It!

Its Best to Lube  X & Y Axis Ballscrews  by Hand  Every Day!

          Use a Coffee-Can with the Same   "Mobil DTE  "Heavy"  ISO 100"   Lube Oil that you are
          using in the Press-Drive Lube Tank,   and using a  2"  Wide Long-Handle Paint Brush,
          Paint  both  Ballscrews  and  Thomson Guide Bars with this Oil.
       Do This Every day!!!

6  ---  Check Resolver-Feedback Packages. 
         I would do this once a year,  every year,   for both  X & Y  Axis.
         When Resolver-Feedbacks Fail,   Axis will Run-Away,  and could Slam into End of Carriage,
         possibly Damaging  Axis Guides,  Ballscrew,  and  Blowing the Servo-Drive.

         Take Package off,  and Spin Small Resolver-Shaft between your fingers.
          It should Spin Very Smooth.     If Rough,  or if there is a lot of  Side-To-Side Play,  or
          a lot of  End-to-End Play,  Replace Package.    Axis will need to be Rezeroed when Reinstalled.

Do NOT Take Your Bad Servo Motor To The  "Local"  Motor Shop!

These Shops Are Set-Up To Rewind  A.C. Electric Motors  Only
And Can NOT Handle  D.C. Servo Motors!

They Usually End Up Damaging Servo Motors Further
As They Try To Figure Out how to take Motor Apart!
Then They  Badly  Cut-The-Commutator,   Install New Bearings,  Paint It,
and  Declare That It's  "Rebuilt",  When In-Fact,   It's Still Burnt-Out!

Because Of Problems Trying To Get Servo Motors Properly Repaired,
I Started Rebuilding Them Myself 25+ Years Ago.

Every One Of Our Motors Is
Tested-Good On a  Actual  Strippit Machine After It's Rebuilt!
We are  The Only Company that Test Motors on a  Strippit CNC Machine.
We Now Keep All Strippit DC Servo Motors In-Stock For Quick Shipping!
Here is a Picture of
Fab Metal's  (Knoxville, TN)
FC1000/3  Machine,
which is  Factory-Wired
for  230 VAC,
that we have added;

2  ---  1.5KVA  Acme Electric Corp.
Cat.  #T-1-11684 
Boost-Buck Transformers
to get the
Whole Machine Voltage
Correct at  225 VAC.

And we have
Never had a Servo Problem
with this Machine!

1  --  Remove Center-Part of Motor Coupling so that   
        Motor can spin freely.
2  --  Un-Hook 2 Motor Armature wires from the Servo Drive.
3  --  Turn Power Supply On.
4  --  Turn the Power Supplied's Voltage down to Zero.
5  --  Hook Power supplies leads to Motors Armature Wires.
6  --  Slowly turn the Voltage up to  30 Volts D.C.
7  --   A  Good  FC1000/3  X-Motor
        will draw  About  1.0  to  1.1  Amps.

Good  FC1000/3  Y-Motor  will draw About  1.0  to  1.5  Amps.

Good  FC1000/3 T-Motor  will draw About  0.6  to  0.7  Amps.

        And Motors will run Smooth and Quiet.

8  --  A Bad Motor will Try to Draw Too-Much Current,   and
       will put my  Power Supply into its  Current Limit Mode
       at over  3 Amps,  and  Motor will Not even turn!

9  --  A Bad Motor will often Have a  Noisy,  Rough,  Burnt, 
       and  Out-Of-Round  Commutator.   Replace Bad Motors!
FC1000/3 Press Drives are Quite Reliable,  but are not trouble free.

They  "Punch Too Fast"  in My Opinion,  which leads to Tool Stripping Trouble if your Tooling is not kept in Excellent Condition,  with proper Die Clearances,  Etc.     The Fast Press Speed also leads to Rapid Clutch & Brake Wear,  Splin-Hub Wear,  Flywheel Bearing Wear,  and Stress on Crankshaft.
Stress on your Crankshaft,
Kind of Looks like This. 
Crankshafts Always Break at the
Inside of Brake Splin Hub.

Strippit used Many Different Versions of Crankshafts, and
is Usually Confused about Which Version you should have in Your Machine,  and they Probably will Not have one anyway.

It is Expensive & a Lot of Work to Replace with a New Crankshaft.

We have Successfully REPAIRED
several Broken Crankshafts.   It is
also Expensive & a Lot of Work.
One of the Best Ways to  Reduce Wear & Tear on Press Drive,  as well as being  Cheap & Easy
(You Do Like  Cheap  &  Easy,   Don't You?)
is to  Slow-Down  the  Press Drive Speed,   and  Therefore  the Punching Speed.
We do this by simply changing the
Press-Drive Motors Shive  (Pulley).
The size we use Slows the Up & Down
Punching Speed about  10%,
and you will Not even notice it!

But it Greatly Reduced Stress and Wear on
All the Press-Drives Components,  and helps cure many Tool & Punching Problems like
"Slow-Strip",   Stuck-Punches,  &  Slug Pop-Up.

Most Original Shives were  6.0" Diameter,
but Strippit did use some other Odd Sizes.
We Recommend Doing This To All
FC1000/3  Machines  and To All
FC1250/30/1500  Machines
With  33-Station Turrets!

We can Provide the  Proper Shive
for your Strippit Machine!

We have  Many Other Recommendations
on how to Improve your Press Drives Reliability
on our  WEB-PAGE     
Please  "Click-On" 
The Button to the Right to go there.

Machine Technologies Co.

Strippit  Machine  Repair-Parts

Strippit  Machine  Repair-Service

Phone  704-233-5229
Above is Select Stainless Co's  FC1000/3  Machine,  in Downtown  Matthews, NC.
Their Machine was wired 460 VAC,  but their Power was about 486 Volts AC,  Too High!

On this Machine,  Prior-Owner had Fitted a Large 120 VAC Control Transformer
(on Back of Control)  to also run their Slug-Conveyor.   This left lots of room next to the Big Servo Transformer to Mount  3 small  Buck-Transformers  shown on the Right.

NOTE!   It is NOT Necessary to Reduce Voltage for the Whole Machine,  so we reduced
it to Just The Servo Transformer.    We used  3   Sola Hevi-Duty  Model  E500D
.5KVA   240 / 480VAC  to  24VAC  Transformers  to do this,  they only cost  $74.00 each.

Before Transformers;
AC Voltage to Servo Transformer  486,       Servo  DC  Buss Voltage  170,   Too-High!

After Buck-Transformers was Added;
AC Voltage to Servo Transformer  449,      Servo  DC  Buss Voltage  154,   Just Right!

3  ---  Check Control  AC Voltage.

In the Servo Cabinet,  2 of the 3 Power-Phases are Picked-Off for the Control Step-Down Transformer to Generate the  120 Volts  AC that  Powers the CNC Control.
I Like this Voltage to be  115  to  125  Volts AC.

If it is Higher  or  Lower,  have a Technician Adjust Change Transformer Taps to Fix it!     It is Very Important that the  Control Voltage be Correct,  or this could cause all sorts of  Various Intermittent Control Failures!       Strippit Got Cheap,  and Some Machines do Not have a Transformer with Proper Over & Under VoltageTaps,  these Machines would need to have Transformer Replaced.

Strippit  FC1000/3 Turret Punch-Press Machines with the  HECC80/3  Type Controls are Popular
as they are  Extremely Fast,  Accurate,  Very Easy to Operate,  and  Easy to Move & Install. 
About 250 of these Machines with  HECC80/3 Controls were built in the years 1981 to 1986, 
and this Web-Page deals mainly with these HECC80/3 Versions.

After 1986 Strippit changed to Fanuc CNC Controls & Servo Drives,  and continued to make more of these fine Machines with GN6 Fanuc Controls & Drives.    Machine Technologies Speciality is the HECC80  Control Machines,  and we Mainly Deal with  HECC80 Controlled Machines.   However, 
many Mechanical Parts on Fanuc FC1000/3 Machines are the Same as on Earlier HECC80 Machines, 
so we Do have Many Repair Parts Available for Fanuc Control FC1000/3 Machines.

Like All Machines,  New and Used,  they had some problems. 
The most common problems were with the Servo Drive  and  Bubble Memory Board.

I have a Separate  Web-Page  on the     Bubble Memory Board     Go There for Its  Problems & Fixes!

We have Learned Much about these Problems over the Years,  and I will share Some of our Solutions.

But it's up to YOU to Implement These Solutions.
I Don't Want To Hear The Stupid
"Well,  It's Run OK like that for Years"
Excuse for Not Doing Them!

If You Don't Do Them,
Do NOT Complain To Me when I Tell You Costs to Repair!

Breaking Your Crankshaft is one of those  "Bad Things"  that you should try Very Hard to Avoid!
10  ---  Tighten  All Connections!
        Turn off  AC Power,  and have a Good Technician  Pull-Up-A-Chair,  and go through the Whole  
        Servo Cabinet,  and Firmly  Tighten  Every Single Nut and Screw in the Servo-Cabinet!    
        Then,  Go to the Other Side of Machine,  and  Tighten  Every Screw in the  Control-Cabinet!
         Over time,Temperature Changes & Vibration will Loosen-Up Connections which will Start Arcing.

        Pay extra attention to Servo-Rectifier and Filter-Capacitors in the Servo Power Supply
        section of Servo-Drive,  as I often see a lot of  Arcing and  Burnt-up Parts there.

A Very Common Problem on a Rectifier Assembly on a  Model 3A Servo.

There are  3 Rectifiers with  2 Large and  3 Small Buss-Bars Connecting them to the
AC Inputs  and  DC Outputs.    Over time,  the Screw Connections get Loose, 
then start  Arcing and Burn-Up  Rectifiers  and  Buss-Bars.

We had to replace 1 Rectifier and make 4 New Buss-Bars to Repair this Assembly.
Keep Screws Tight!     Tighten Yearly,  during your  Preventive Maintenance Week.
  Yeah,   I  Know,   You Don't Do That.

We have Other Recommendations on how
to Improve your Servo Drive Reliability
on these  3  WEB-PAGES
Please  "Click-On"  The Buttons
to the Right to go there.

2  ---  Check that the Regen Circuit is Functioning Correctly!

When a Servo-Motor Decelerates,  it becomes a  D.C.-Generator with all the Axis Momentum being Converted into D.C. Power that Backfeed's into the Servo Drives Power Supply.
This causes the Servo Power Supply Voltage to Rise,  and if it gets Too-High,
it can Blow-Out the Servo Drive Modules and Boards,  Just like in  Discussion #1  above!

The Regen Circuit Senses this Hi-Voltage,  and at about  182VDC,   it Turns-On,
and Dumps this Excess Power into Load-Resistors until the Voltage Falls to about 178 VDC.

Unfortunately,  this is  Not-Easy to Check,  and I Do Not know of other Technicians besides myself
that can do this.   I have several different Test Procedures for these Circuits.   One I use is to Monitor the D.C. Servo Power Supply,  and Catching & Seeing this Regen Turning On & Off,  with my  Digital
Tektronix Oscilloscope,  on a Strippit  FC1000/3 Machine when making  30 Inch Y-Axis Moves.

FC1000/3's  below  #066  usually have the  "3"  Servo Drive that does  Not work well,
and uses the  PSRG3  Regen Board  and  SCR's that are  Very Hard to Test and Repair.

FC1000/3's  above  #066  have Improved  "3A"  Drive that does works well,  and I have a Very Good
Test-Station here in my Electronics Lab to Test and Set-Up the  PSRG5  Regen Board.

There are Too Many Variables to discuss here,  but Regen Board should be Checked to see it Turns
On & Off at Proper Voltages,   All Fuses are Good,  and  Regen Load Resistors are Not Melted!     
The  PSRG5  Regen Board  Can be Sent-In to  Machine Technologies  for  Set-Up  and  Up-Dating.

To Recap,   
Do All The Recommended Procedures
To  Reduce Expensive Machine  &  Control  &  Servo Drive Failures!

1    ---   Reduce incoming Servo  A.C. Voltage to  230 / 460  Maximum
            to  Reduce the  DC Servo Drive Buss Voltage  to  about  155 VDC!
2    ---   Make Sure  Servo Drive Regen Circuit is Working!
3    ---   Make Sure Control  AC Voltage  is Proper  115  to 125VAC !
4    ---   Reduce  X & Y  Axis Speed with a   F2   or   F15   Feedrate in  All  Your Part Run Programs!
5    ---   Service Servo Motors Regularly!    Check  Brushes,  Springs,  Armature,  Commutator.
6    ---   Inspect  Axis  Feedback Packages Yearly,  and  Replace Worn Packages!
7    ---   Add  Air Condition to Servo-Cabinet!!!
            Maintain Control-Cabinet   AND  Servo-Cabinet Air Conditioner  70  to  75  degrees!!!
8    ---   Send-In  PWMC7  &  PWMP8  Boards  to be  Updated with New Capacitors!
9    ---   Oil  Guide Bars and Ballscrews!
10  ---   Tighten  All  Connections in  Servo  &  Controls Cabinets!
11  ---   Install a  Good  8  Foot Ground Rod!
12  ---   Properly Install Machine  &  it's  2 Cabinets!
13  ---   Check all Axis  Slow-Down  and  Limit Switches!
14  ---   Retune  Axis Servo Drive  "Gain"  to  Reduce Servo Drive Stress!
15  ---   Make sure  Servo Drive Fan is Working!
16  ---   Change  Press-Drive Motor Shive to  Reduce Axis   "Jam-Ups"!
17  ---   Use Only  Sharp  &  Properly Adjusted  Tooling  with  Correct Die Clearances!
18  ---   Never  Even Turn-On  Machine and CNC Control  if Shop Temperature is Below  50 Degrees!!!

  If You can't be Bothered to Invest some Time & Money to help keep your
  Critical Punch Machines Running,   don't  Cry to Me  when they go  "Down".
More Servo Motor Information
is on This New Web-Page,  Take A Look!
Above is another Strippit  HECC80/3 Control  FC1000/3 in Downtown Matthews NC.
Machine was wired for 460 VAC,  but their Power was about 486 Volts AC,  Too High!

NOTE!   It is NOT Necessary to Reduce the Voltage for the Whole Machine!
So we decided to reduce  A.C. Voltage to Just the Servo Transformer.
We Mounted  2  small Buck-Transformers,  as shown,  on the Back of Servo Cabinet.

We used  2   Acme Electric Co.  Catalog #T-1-81065  
.5KVA  Buck/Boost  240 / 480 VAC   to  24 / 48 VAC   Transformers to do this.

If this was a  230 Volt Factory Wired Machine,  Amperage requirement would Double,
so we would use   2  --  1.0 KVA Transformers instead of the   2  --  .5 KVA

Acme has Much Online Information on  Using & Wiring  Buck/Boost Transformers  in
their  Online Catalog at     Go Check it Out!

Before Transformers;
AC Voltage to Servo-Transformer  486,      Servo  DC Buss Voltage  170Too-High!

After  Buck-Transformers was Added;
AC Voltage to Servo-Transformer  439,      Servo  DC Buss Voltage  150Perfect!

The above 3 Customer's have done  Everything we told them to do to Increase Reliability,
as noted on This Web-Page,  such as;
----   A.C. Servo Buck Transformers to Lower the Servo DC Buss Voltage to about  155 VDC
----   Updated  PWMC7  &  PWMC8  Servo Drive Boards
----   "Retuned"  PWMC7  &  8PWMC  Boards for  Less Gain  &  Servo Stress
----   Reduce  X  &  Y  Speed by adding  F2000 Feedrate  to  All Their  Part-Programs
----   Change  Press-Drive Motor Pulley  for slighly Slower Punching Speed
----   Installed Heavy-Duty Lifter Springs for  Better Tool Stripping
and they have  ZERO  Servo  Problems!

Luckily for Me,   Most Customers do Not do these Updates,  so I do a  Brisk  Service  &  Repair Parts
Business with them,  and  I can keep ahead of my  Wife's Spending.    The Choice is Yours!

If I don't Answer the Phone,
it's cause I'm Out Traveling,
Leave  A  Message!

We had a Pretty Good Apartment Location Here,
Don't you think?

Hint,  that's the Back of  The Louvre   on Right,
The  Seine River   on Left,
and some  Old Tower   in the Middle.

You Should See It at Night!
17 ---  Intermittent Servo Inhibits.

Once or Twice a Year,  I see a  FC1000/3 that the Control thinks everything is OK with No Error Messages on the CRT Display.     This Condition could be Intermittent,  or could be Constant.
If you grab  X or Y Ballscrew you can Easily Turn Them  Proving that the Servo Drive is OFF,   but  Control does Not know it!    It you try to Move the  X,  Y,  or  T Axis,  they will Not Move and you get a Excess Error Message,  which means that the Axis is Not where Control thinks it should be.

This is Usually caused by an Internal Inhibit caused by the  RL1 Relay Contacts  4 & 7 being Closed,
but the Contacts are Old & Corroded,  so that  "R-Inhibits"  from  X,  Y,  &  T   TB302-R  Terminal Strips
are Not Pulled-Down to Ground because of Bad Connection between the  4  &  7  Contacts.

You can Easily Check this by Monitoring Voltage at   X  or  Y   TB302-R  Terminal.
D.C. Voltage  ---   Less that  1 Volt,   The Normal  Servo-On  Un-Inhibited Condition.
D.C. Voltage  ---   About  7 to 8 Volts,  RL1 Relay is Not Pulled-In,  The Servo is Off & Inhibited.
D.C. Voltage  ---   Voltage Drifting around from  1 to 8 Volts,  Caused by Dirty or Corroded  RL1 Relay
                               Contacts,  and The Servo Drive may Turn On & Off and Work Intermittently.

Unfortunately,  G.E. Buried this RL1 Relay Behind  PSRG Board where you Can Not Get to it,  or
even see it!    They also used an Odd Type Relay that is Bolted Directly to Panel,  and has Stake-On
Terminal Wire Connections,  not a nice & easy Relay Socket so that you could Plug-In a new relay.

So,  to Repair,  I replace with a different Type of Relay  (Grainger  #1A488 Relay  and  #5X853 Socket) and I use a Relay Socket so it can be Easily Replaced.     I Also make a  L-Bracket   (You are in a Sheetmetal Shop after All!),   Cut all the Wire-Ties,   and  Relocate this New  RL1  Relay & Socket,  
and the Related  RL3  Relay Panel,   to a Place where I can Easily See and Work on it.

Problems with RL1  &  RL3 Relay Circuits can also cause  X, Y, T Servo Contactors from Pulling-In.
CNC Controls will Not  "See"  This,  so there will be No Servo Error Messages when  "Message" Softkey is Pushed.    Test this by  "Pushing"  X & Y  Axis by Hand,  if you can Push the Axis,  your Servo-Drives are Not-On,  and this is probably caused by an  Inhibit Problem  or Contactor Problem.

Note!   This is Tricky-Work,  and  Should Only be Done by a Experienced Technician  who Also Has Actual  G.E. Servo Manuals as a Guide,  as  G.E. Wired these Panels  Several Different Ways and
Wiring Mistakes could be very Costly!      I have some Servo Manuals still In-Stock & Available.

On Occasion,  I have had  1 of the  1/4-Amp.  Fuses on  PSRG5 Servo Board  Blow from old-Age, 
which can also cause this Servo-Off Problem.
Check all Fuses and that the Correct  DC Voltages are Present on the TB201 Terminals.

A Burned-Out Contactor Coil is also a Very Frequent cause of  No Servo Drive with No Messages.