Harmonic Drive MMA Series, Manual, Page: 47 / 62

3-3 Location and installation
3-6
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Installation
When installing an MMA series motor, ensure that it is installed accurately and do not tap with a
hammer, etc. The motor houses an encoder. Excessive impact may damage the encoder.
Installation procedure
1
Align the axis of rotation of the motor and the
load mechanism precisely.
Note 1: Perform this alignment carefully, especially when a
rigid coupling is used. Even slight misalignment
may cause the allowable load of the motor to be
exceeded, resulting in damage to the output shaft.
2
Connect the servo amplifier and wiring.
An extension cable is provided. Use it when wiring the servo amplifier. For details on wiring, refer
to [1-13 Cable specifications] (P1-19) and [Related manual] (P6)
3
Wire the motor cable and encoder cable.
Do not pull the cables with a strong force. Doing so may damage the connectors. Install the cable
with slack and do not to apply any tension to the motor. Provide a sufficient bending radius (at
least six times the cable diameter), especially when the cable flexes.

Do not bring strong magnetic bodies (magnet chucks, permanent magnets, etc.) near
the rear cover of the motor. Encoder abnormality may result.

This encoder retains absolute positions when the power is turned OFF by means of the
servo amplifier's battery or its own built-in capacitor. If the encoder cable is
disconnected for maintenance, etc., turn ON the servo amplifier power and charge the
backup capacitor first. After 3 hours of charge, the encoder cable can be disconnected
for 30 minutes, provided that the axis is stopped and ambient temperature is 25
℃
.
However, when the backup capacitor is deteriorated, the absolute positions may not be
retained.
Do not disassemble/reassemble the motor.
The motor uses many precision parts. If the motor is
disassembled/reassembled by the customer, it may cause motor burnout or
uncontrollable operation, resulting in a fire or injury.
WARNING
Output
shaft
Flange