Yaskawa SmartTrac PG Card - Manual (Page 17)

SMART TRAC PG Card
Technical Manual TM 3554-0020 Testing Card Installation
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Checking Pulses at Input to Smart
Trac PG Card
NOTE: The following procedure describes checking feedback (channel 0)
encoder pulses at terminal J3 and follower (channel 1) encoder pulses at
terminal J5.
1. Remove power from L1, L2 and L3. Wait for the CHARGE light to go
out.
2. Connect the common of the oscilloscope to TP11 ( +5 V ISO Common ).
NOTE: This procedure requires a two-channel oscilloscope to view the
relationship between A+ and A- at the same time.
3. To check A to /A: Connect one channel of the oscilloscope to J3-1 if
checking channel 0 A pulse or J5-1 if checking channel 1 A pulse.
Connect the second channel to J3-2 (/A pulse) if checking channel 0 or
J5-2 (/A pulse) if checking channel 1.
4. Set the oscilloscope for 5V/div, 50ms/div, normal trigger, and rising
edge trigger.
5. Apply power to the Smart Trac AC1, but DO NOT apply a RUN
command.
6. 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).
7. Disconnect the two oscilloscope channels. Reconnect them to terminals
J3-3 or J5-3 (B pulse) and J3-4 or J5-4 (/B pulse).
8. To check B to /B: Turn the motor shaft by hand. You should see pulses
on both channels and 50% duty cycle. Again, the pulses should be
separated by 180 electrical degrees (one the inverse of the other).
9. To check A to B, Channel 0: Disconnect the two oscilloscope channels.
Reconnect them to terminals J3-1 (Channel 0 A pulse) and J3-3
(channel 0 B pulse) Check the relationship between A and B. They
should be 90 degrees out of phase.
10. To check A to B, Channel 1: Disconnect the two oscilloscope channels.
Reconnect them to terminals J5-1 (Channel 1 A pulse) and J5-3
(channel 1 B pulse) Check the relationship between A and B. They
should be 90 degrees out of phase.
11. If one or both channels do not have the correct pulses present (i.e.
missing pulses, incorrect duty cycle, improper voltage, etc.), check
pulses at the motor (next procedure).