Teknic EF-785, Installation Manual

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V
E R S I O N
1 . 4 2 / A
U G U S T
2 6 , 2 0 0 5
eF-785
Main
Option
SSt Servo Drives
Daisy-chained wiring topology
• Daisy-chained loop This topology is only slightly different from
the daisy-chained wiring described previously. In the loop
version, the “last” drive in the chain is connected back to the eF-
785. The daisy chain loop offers the advantages of redundancy
and improved performance. Should any
one of the cables
delivering power to the drives become open or intermittent, the
drives will continue to receive power and therefore continue to
operate. Also, with the additional cable supplying the drives,
supply-to-load resistance is reduced and, subsequently, the I
2
R
power loss in the cabling is reduced. This parallel power path
provides improved machine performance and reliability. As with
the daisy-chained wiring method described previously, the drive’s
power circuits should be isolated from the machine chassis and
any control circuits connected to them.
eF-785
Main
Option
SSt Servo Drives
Daisy-chained loop wiring topology
• Central star If you are connecting motor drives other than
Teknic’s, and they don’t have electrical isolation between DC bus
power and the control circuitry, then you need to use this method
of wiring in order to prevent ground loops from occurring in the
machine. Each drive is wired individually to the eF-785 by using a
terminal block or distribution panel to bring power to each drive
separately.