Inovance MD500 Series - Breaker & Fuse Selection; Shielded Cable

9. Technical Data
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9.1.6 Breaker & Fuse Selection
Earth leakage current of AC drive is larger than 3.5 A, requiring grounding protection.
The AC drive produces DC leakage current inside protective conductor, thus a B-type (delay-
type) leakage breaker must be used.
When leakage breaker acts accidentally, you can:
● Use a leakage breaker of higher rated action current or use a delay-type leakage breaker.
● Lower the carrier frequency of AC drive.
● Shorten the length of drive cables of motor.
● Take leakage current suppression measures.
Recommended leakage breaker manufacturers are CHINT and Schneider.
For selection of fuse and breaker, see
8
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9.1.7 Shielded Cable
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Requirements for Shielded Cable
Shielded cable must be used to satisfy EMC requirements of CE marking. Shielded
cables are classied into three-conductor cable and four-conductor cable. If conductivity
of cable shield is not sufcient, add an independent PE cable, or use a four-conductor
cable, of which one phase conductor is PE cable.
Three-conductor cable and four-conductor cable are shown in the following gure.
PE
PE conductor
and shield
Shield
Shield
PE
PE
Shield
To suppress emission and conduction of radio frequency interference effectively,
shield of cable is cooper braid. Braided density of cooper braid should be greater than
90% to enhance shielding efciency and conductivity, as shown in the following gure.
Cable core
Internal insulator
Copper braidCopper shield
Insulation jacket