Yaskawa SmartTrac PG Card - Manual (Page 18)

SMART TRAC PG Card
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Testing Card Installation Technical Manual TM 3554-0020
Checking Pulses at a MagneTek VCM
Motor
1. Remove power from L1, L2 and L3. Wait for the CHARGE light to go
out.
2. Take apart the military-style, circular connector at the motor.
3. Connect the common of the oscilloscope to pin F of the circular
connector.
4. Connect one channel of the scope to pin A of the circular connector. If
the oscilloscope is two channel, connect the second channel to pin H.
5. Set the oscilloscope for 5V/div, 50ms/div, normal trigger, and rising
edge trigger.
6. Apply power to the Smart Trac AC1, but DO NOT apply a RUN
command.
7. Turn the motor shaft by hand. You should see pulses on both channels
and 50% duty cycle. The pulses should be separated by 180 electrical
degrees (one the inverse of the other).
If no pulse can be seen on any of the four connector pins (A, B, H or I), check
the power supply between pins D and F. It should be at or near 12 VDC. If not,
check the power supply at the Smart Trac PG card, between J3-7 and J3-8. If the
power supply is not at or near 12VDC, check to make sure J2 is mated with 4CN
on the inverter control board. If it is properly mated, replace the Smart Trac PG
card.