Mitsubishi MELDAS MDS-C1 Instruction Manual page 168

(7) Checking the Z phase and A phase difference
Check the output signal waveform by measuring the signals of the check terminals on the PCB
with the DC range of the synchroscope.
A phase output signal........ Across A-G
Z phase output signal........ Across Z-G
The output signal waveform is confirmed during motor forward run and reverse run. Set the
synchroscope as follows to measure the waveform during each run direction.
During forward run ....... Apply a trigger at the rising edge of the Z phase output signal
During reverse run ....... Apply a trigger at the falling edge of the Z phase output signal
The phase difference for the Z phase signal and A phase signal is defined as follows.
During forward run ....... Time difference between Z phase output signal rising edge and A
During reverse run ....... Time difference between Z phase output signal falling edge and A
Confirm that the phase difference between the Z phase to the A phase is within ±25% during both
forward and reverse run when one cycle of the A phase signal is calculated as100%. If the output
signal waveform is not as shown below, refer to the next section "(8) Adjusting the Z phase and A
phase difference" and adjust.
One A phase cycle = 100%
A phase
Q point
0V
Tolerable
range of phase
difference
±25%
Z phase
Phase difference of A phase and Z phase
Confirming the Z phase signal phase difference
during forward run
(8) Adjusting the Z phase and A phase difference
1) Stop the motor, and make sure that the detection gears are not rotating. The sensor could be
damaged if adjustments are carried out while the gears are rotating.
2) Using a clearance gauge, adjust so that the gap between the sensor direction surface and the
detection gears' circumference is 0.15±0.01mm, and loosen the sensor fixing screw.
3) The phase difference of the Z phase to the A phase can be adjusted by rotating the sensor as
shown on the right. At this time, rotate the sensor a little bit while using the marking lines on
the sensor and installation seat as a guide.
4) Tighten the sensor fixing screw so that the sensor
does not move, and confirm that the gap between the
sensor detection surface and detection gears'
circumference is 0.15 ± 0.01mm. Then, rotate the
gears and confirm the phase difference as explained
above.
5) When the phase difference is within the tolerable
range, apply a locking agent on the sensor fixing
screw, and then fix the sensor. Check the gap again
after fixing the sensor.
3. Setup
phase output signal zero point (Q point)
phase output signal's 1/2 cycle point (R point)
Apply a trigger at the rising
edge of the Z phase
H level (reference
voltage +15V)
L level
3 - 89
One A phase cycle = 100%
A phase
R point
0V
Tolerable
range of phase
difference
±25%
Z phase
Phase difference of
A phase and Z phase
Confirming the Z phase signal phase
difference during reverse run
Sensor
installation
seat
Marking
Rotate
line
Adjusting the Z phase difference
Apply a trigger at the falling
edge of the Z phase
H level (reference
voltage +15V)
L level
Sensor
fixing
screw