[Redzilla]

I just bought another J325 and I can't get my axis lag to .0000 +-.0002 so the control won't let me run any G0 in position codes,I've adjusted the servo amps and even swapped servo amps out of my other mill that has .0000 axis lag and it stays the same X.0009 Y.0011 Z.0008 axis lag, I've taken the brushes out of all of the servos and blown all of the dust out I had to do this because I was getting a motor overload fault on the control which was a bad brush spring on the Z axis, I'm getting 104 VDC at the bus capacitor and +&-15 vdc and the servo amps, does anyone have any suggestions as to what to check now?

[DNS1]

If this is still an issue I can help.

Mike

[Redzilla]

If this is still an issue I can help.

Mike

yes I don't know what to check next I'm getting a .023 volt signal leaking to the servo drives from somewhere, I've even swapped the servo drive board in the control card rack with no change, I think it's something simple but I haven't found it yet.

[DNS1]

Your first check is the Dynapath power supply. The power supplies are Dynapath's main weak point. You can check all of the DC outputs with a DVM. First check the DC outputs in the DC range(5,-15,15 and 24VDC). Then check for the ripple in the AC Range. An Oscilloscope work best for ripple testing.

If the Dynapath power supply has significant ripple it wouldn't be able to read the ADC for the tachs accurately.

Second, Check if the servo drive and Dynapath controls are grounded properly. They should be grounded to the back panel. Remove any paint from the ground connections.

Mike

[Redzilla]

Your first check is the Dynapath power supply. The power supplies are Dynapath's main weak point. You can check all of the DC outputs with a DVM. First check the DC outputs in the DC range(5,-15,15 and 24VDC). Then check for the ripple in the AC Range. An Oscilloscope work best for ripple testing.

If the Dynapath power supply has significant ripple it wouldn't be able to read the ADC for the tachs accurately.

Second, Check if the servo drive and Dynapath controls are grounded properly. They should be grounded to the back panel. Remove any paint from the ground connections.

Mike

I don't have a oscilloscope but the voltages are all good, I've checked all of the grounds they test good also

[DNS1]

What happens when you rapid an axis? Are there any error codes?

[Redzilla]

What happens when you rapid an axis? Are there any error codes?

Not when I have the servo amps adjusted right I've been playing with them with no luck, my +15vdc has 70MV of ripple -15vdc has 14MV all the others are at 4mv

[DNS1]

I just bought another J325 and I can't get my axis lag to .0000 +-.0002 so the control won't let me run any G0 in position codes.

Does your program halt at G00 or does it halt after the rapid?
Are there any errors shown when you press fault key?

,I've adjusted the servo amps and even swapped servo amps out of my other mill that has .0000 axis lag and it stays the same X.0009 Y.0011 Z.0008 axis lag,.

Having the same axis lag is odd.
Go to mode select 5 (setup), key in TM4 and depress the E-Stop button. Does the Axis lag change?Manually turn the X axis. Does the axis lag change?

[underthetire]

I assume you mean 0 lag at stand still? You just need to adjust the balance pot on the drives. If it jumps around, you may need a new filter cap on the drive power supply.

Sent from my A3-A20FHD using Tapatalk

[Redzilla]

Does your program halt at G00 or does it halt after the rapid?
Are there any errors shown when you press fault key?



Having the same axis lag is odd.
Go to mode select 5 (setup), key in TM4 and depress the E-Stop button. Does the Axis lag change?Manually turn the X axis. Does the axis lag change?

Yes it halts on G00 codes thinks it's not in position but it'll run fine with a G01

[Redzilla]

I assume you mean 0 lag at stand still? You just need to adjust the balance pot on the drives. If it jumps around, you may need a new filter cap on the drive power supply.

Sent from my A3-A20FHD using Tapatalk

I've tried adjusting the balance pot it's not that, are you talking about the big capacitor or one on the power supply itself?

[DNS1]

Don't bother with the TM4, E-Stop test. You wouldn't be able to run G01 in position if the Dynapath controller was at fault.

I believe your tach is out of adjustment.
The tach value is a static value that doesn’t change from machine to machine with the same tach. The tach adjustment is for conditioning the input signal of the tach. If the tach gain is too high clipping will occur. If the tach gain is too low trajectory will be affected.
Also if the tach is set too high the signal pot will run out of adjustment. If the tach is set too low the balancing pot will run out of adjustment.

Setting the J325 to factory specification:

I recomend that you save all of the current setting on a spread sheet and mark the individual axis cards.

Setup Procedure for Servo Dynamics Servo Drives

1. With the boards removed from the chassis, hook a digital ohm meter from TP1 to the left side of R19, adjust R44 for 7.9K Ohm.
2. With one lead of the meter on TP1 and the other lead on:
TP2, adjust Aux for 0 ohms
TP3, adjust Sig for 4.8K ohms
TP4, adjust Tach for 4.4K ohms
TP5, adjust CMP for 570 ohms
NOTE: All plugs must still be disconnected

3. Adjust Current Limit to Maximum Clockwise (CW).
4. Install the modules and turn power on.
5. Reset E-stop, reference machine. Go to mode select 5 (setup), key in TM4, Enter (servo adjust). Then mode select 0 (jog), enter 1 (medium jog), set feederate override pot to maximum CW.
6. Adjust balancing pot for zero standing axis lag +/-.0002
7. Jog the axis, adjust Signal pot for .015” axis lag. (All axis should have the same value or circular milling will be irregular. )

This is the procedure that my Tree 325 manual specifies. I have used this simplified procedure on my 325 and have found that after you have finished step 7 no other adjustments are required and the servo/amplifiers are back to factory specifications.

This will solve the servo balancing issue, but you may still have rapid halts. If this is still an issue, measure the voltage across the Servo drives capacitor while rapiding(as fast as you can) with jog. I believe 89 Volts is too low. If this is the case you will need to replace the capacitor.

[Redzilla]

Don't bother with the TM4, E-Stop test. You wouldn't be able to run G01 in position if the Dynapath controller was at fault.

I believe your tach is out of adjustment.
The tach value is a static value that doesn’t change from machine to machine with the same tach. The tach adjustment is for conditioning the input signal of the tach. If the tach gain is too high clipping will occur. If the tach gain is too low trajectory will be affected.
Also if the tach is set too high the signal pot will run out of adjustment. If the tach is set too low the balancing pot will run out of adjustment.

Setting the J325 to factory specification:

I recomend that you save all of the current setting on a spread sheet and mark the individual axis cards.

Setup Procedure for Servo Dynamics Servo Drives

1. With the boards removed from the chassis, hook a digital ohm meter from TP1 to the left side of R19, adjust R44 for 7.9K Ohm.
2. With one lead of the meter on TP1 and the other lead on:
TP2, adjust Aux for 0 ohms
TP3, adjust Sig for 4.8K ohms
TP4, adjust Tach for 4.4K ohms
TP5, adjust CMP for 570 ohms
NOTE: All plugs must still be disconnected

3. Adjust Current Limit to Maximum Clockwise (CW).
4. Install the modules and turn power on.
5. Reset E-stop, reference machine. Go to mode select 5 (setup), key in TM4, Enter (servo adjust). Then mode select 0 (jog), enter 1 (medium jog), set feederate override pot to maximum CW.
6. Adjust balancing pot for zero standing axis lag +/-.0002
7. Jog the axis, adjust Signal pot for .015” axis lag. (All axis should have the same value or circular milling will be irregular. )

This is the procedure that my Tree 325 manual specifies. I have used this simplified procedure on my 325 and have found that after you have finished step 7 no other adjustments are required and the servo/amplifiers are back to factory specifications.

This will solve the servo balancing issue, but you may still have rapid halts. If this is still an issue, measure the voltage across the Servo drives capacitor while rapiding(as fast as you can) with jog. I believe 89 Volts is too low. If this is the case you will need to replace the capacitor.

I've already adjusted the servo amps to factory specs with no luck I have another j325 setting right beside this one I've even swapped parts back and forth with no luck, the servo amp is receiving a very small go command from the control for some reason .007 volts

[DNS1]

Go to mode select 5 (setup), key in TM1, Enter (rapid override), set the feed rate override to 1/4 turn from 0. Will G00 execute?

[DNS1]

Is this a Dynapath System 10/20 or a Delta 10/20?

the servo amp is receiving a very small go command from the control for some reason .007 volts

,I've adjusted the servo amps and even swapped servo amps out of my other mill that has .0000 axis lag and it stays the same X.0009 Y.0011 Z.0008 axis lag,

I think your on the right track. The Dynapath controls are creating an overall analog offset that is effecting the balance. If you're swapping out cards and getting the same axis lag from 2 machines there must be a DC offset that the balance pots cannot compensate for from the Dynapath controls.

What was the the ripple on the Dynapath power supply. On the Dynapath System 10/20 it's the card on the far right side and on the Delta it has an external power supply mounted on the right side of the dynapath case. (5,-15,15 and 24VDC)

Take pictures of all the connections on the Dynapath controls. Remove and clean all of the boards. Carefully inspect the cards traces for contaminates.

[cnctoolman]

following as I just had the same thing happen today. Machine has been running fine and then all of a sudden,z-axis error. Tried adjusting the balance pot and aswell cant get it to .0002 at all. hasnt done this before. can get it close, but once I jog an axis to see the signal lag, it changes when standing still.

[cnctoolman]

going to try and redo the tune on the z-axis. Have not done it yet before. which plugs are you referrning to with this -NOTE: All plugs must still be disconnected?

[Redzilla]

going to try and redo the tune on the z-axis. Have not done it yet before. which plugs are you referrning to with this -NOTE: All plugs must still be disconnected?

Remove the plug across the top, that's what mine does I can adjust the balance pot and get it to .0000 in +or- but as soon as you change direction the other side will be at like .0022, good luck on finding the problem I'm about to give up I've checked and tried everything I can think of

[cnctoolman]

Remove the plug across the top, that's what mine does I can adjust the balance pot and get it to .0000 in +or- but as soon as you change direction the other side will be at like .0022, good luck on finding the problem I'm about to give up I've checked and tried everything I can think of

Hopefully I can get it figured out. Mine is just on the z-axis. It's stuck at the moment at .0008. Hopefully after a retune, it will get there.

[cnctoolman]

Well I switched cards on the y and the z and the problem switched to the y, so going to do a tune.
What I found with initial tests
Tp1 to r19- 8.3
To tp2 - 0
To tp3 - 7.9
To tp4 - 7.7
To tp5 - 892