Panasonic minas a series Operating Manual page 69

Protective Functions
Alarm
Protection
Code No.
* Encoder A/B- No A- and B-phase pulse is detected. The 11-
20
wire encoder failed.
phase
error
21 Due to no communication between the encoder
* Encoder
communication and driver, the detective function for broken en-
error coder wires is activated.
22
* Encoder The connection between the 11-wire encoder
and driver is broken. The encoder rotates higher
connection
than the specified rate when control power is on
error
.
* Encoder 23 The encoder sends an erroneous data mainly
communication due to noises. The encoder is connected cor-
data error rectly, though the data is not correct.
Position The position error pulse is larger than Pr63 (po-
24
error sition error limit). The motor operation does not
respond to the commands.
Hybrid When the driver of the full-closed version is un-
25
der the full-closed and hybrid control with an
error
external encoder, the load position detected by
the external encoder and the motor position
detected by the motor encoder are beyond the
limit specified by Pr73 (hybrid error limit).
Over-speed
26
The motor velocity exceeds the specified limit.
Cause
- 68 -
Countermeasures
Correct the encoder wiring per the wiring dia-
gram. 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 require-
ment. You should not bundle the encoder wires
and motor wires together. Connect the shield to
FG. See the encoder wiring diagram.
Check whether the motor operates per the po-
sition 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 accelera-
tion and deceleration time. Reduce the load and
velocity.
Check the connection between the motor and
load. Check the connection between the exter-
nal encoder and driver. Correct the values of the
external scale numerator and denominator re-
garding parameters Pr74, Pr75, Pr 76 and Pr77.
Increase the value of Pr73. Increase the value
of Pr71 (hybrid switching time).
Decrease the target speed (command values).
Decrease the value of Pr50 (velocity command
input gain). Adjust the scale ratio so that the fre-
quency of the command pulse is 500 kpps or
less. If an overshoot occurs, readjust the gains.
Correct the encoder wiring per the wiring
diagram.ÅB