9.2 Wiring Servomotors and SERVOPACKs
9.2.1 Wiring Precautions
9
Connection
s
between
S
ervomotor
s
and
S
ER
VOP
ACK
s
9-9
Precautions for Flexible Cables
•
The Flexible Cables have a service life of 10,000,000 operations minimum when used at the
recommended bending radius of 90 mm or larger under the following test conditions. The
service life of a Flexible Cable is reference data under special test conditions. The service life
of a Flexible Cable greatly depends on the amount of mechanical shock, how the cable is
attached, and how the cable is secured.
Test Conditions
•
One end of the cable is repeatedly moved forward and backward for 320 mm using the test equip-
ment shown in the following figure.
•
The lead wires are connected in series, and the number of cable return operations until a lead wire
breaks are counted. One round trip is counted as one bend.
Note: The service life of a Flexible Cable indicates the number of bends while the lead wires are electrically
charged for which no cracks or damage that affects the performance of the cable sheathing occur.
Breaking of the shield wire is not considered.
•
Straighten out the Flexible Cable when you connect it. If the cable is connected while it is
twisted, it will break faster. Check the indication on the cable surface to make sure that the
cable is not twisted.
•
Do not secure the portions of the Flexible Cable that move. Stress will accumulate at the
point that is secured, and the cable will break faster. Secure the cable in as few locations as
possible.
•
If a Flexible Cable is too long, looseness will cause it to break faster. It the Flexible Cable is
too short, stress at the points where it is secured will cause it to break faster. Adjust the cable
length to the optimum value.
•
Do not allow Flexible Cables to interfere with each other. Interference will restrict the motion
of the cables, causing them to break faster. Separate the cables sufficiently, or provide parti-
tions between them when wiring.
Bending radius
= 90 mm
Travel distance: 320 mm
Fixed end
End of travel
