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XYZ Machine Tools Ltd
XYZ Bed Mill Safety, Installation, Maintenance, Service & Parts List Manual
Note: To avoid pulling the wires out of the connector, use the loop to pull the connector from the Servo
Driver.
If the problem moves to the other axis and clears up from the original axis, replace the Servo Driver.
4.6
Scales
4.6.1
Measurements Do Not Repeat
1.
Determine if the error in repeatability is random or accumulating:
Mount a dial indicator in the quill.
Touch off a fixed point on the table and set the DRO to 0.
Traverse away approximately 150 mm.
Return the touch off again.
Write down the reading on the DRO.
Do not Re-zero the DRO, traverse away and return several times.
Write down the DRO readings
Random error will be unpredictable and give scattered readings, adding and/or subtracting the
error after each traverse with no pattern. See Step 2.
Accumulating error will add roughly the same amount to the reading after each traverse. See
Step 3.
2.
For random error, look for problems in the set-up of the scale that have resulted in a loss of
rigidity. Common sources of random error include:
Loose scale mounting hardware.
Loose reader head.
Very loose motion of the table or saddle.
3.
Accumulating error is commonly the result of:
Scale out of parallel to the axis travel.
Dirt or chip on the Newall scale.
Broken Newall scale.
4.7
Electrical
DANGER!
Hazardous voltages exist within the machine. Danger of death by electrocution.
Only electrically competent personnel should undertake diagnostics on the electrical systems
of the machine
4.7.1
Checking AC Voltage
This procedure tests for the 115V power for the control.
Use a voltmeter on AC volts range.
Acceptable range is 100V to 130V.
Note: systems running consistently close to the low values may have problems when normal voltage
fluctuations push the voltage out of the acceptable range.
Test at the following locations:
Problems Here:
May Indicate:
Power in and out of transformer.
Fuses blown.
Check the 110 power cord to the pendant.
Power cord defective
Check fuse on pendant.
Fuse blown.
