- 64 -
Protection
* Encoder A/
B-phase
error
*
Encoder
communication
error
* Encoder
connection
error
*
Encoder
communication
data error
Position
error
Over-speed
error
Command
pulse sealer
error
Protective Functions
Alarm
Code No.20
21
22
23
24
26
27
Countermeasures
Correct the encoder wiring per the wiring
diagram. Correct the connection of the
pins.
Make sure that the power of the encoder
is 5VDC ±5% (4.75 to 5.25V). Especially when
the wire length is long, it is important to meet
this requirement. You should not bundle the en-
coder wires and motor wires together. Connect
the shield to FG. See the encoder wiring dia-
gram.
1) Check whether the motor operates per
the position command pulse or not. See
the torque monitor to check if the output
torque is saturated. Readjust the gains.
Maximize the value of Pr5E (torque limit
set-up). Correct the encoder wiring per
the wiring diagram. Increase the accel-
eration and deceleration time. Reduce
the load and velocity.
2) Increase the value of Pr63.
Do not give excessive speed commands. Check
the frequency of the command pulse and scale
ratio. If an overshoot occurs due to wrong gain
adjustment, readjust the gains. Correct the en-
coder wiring per the wiring diagram.
Check the set values of Pr46 through 4B.
Adjust the scale ratio so that the fre-
quency of the command pulse may be
500 kpps or less.
Cause
No encoder A- and B-phase pulse is de-
tected. The encoder failed.
Due to no communication between the
encoder and amplifier, the detective func-
tion for broken encoder wires is activated.
The connection between the encoder and
amplifier is broken.
The encoder sends an erroneous data
mainly due to noises. The encoder is con-
nected correctly, though the data is not
correct.
The position error pulse is larger than
Pr63 (position error limit).
1)
Operation of the motor does not follow the
commands.
2)
Pr63 value (Position error limit) is smaller.
]
The motor velocity exceeds the specified limit.
The scale ratios set by Pr46 through Pr4B (nu-
merator of 1st to 4th command scale) are not
correct.