Requirements on fuses and circuit breakers
• The fuses must comply with any local codes or regulations in place. In general, type
gG (IEC 60269) or UL type T fuses are suitable; however in some cases type aR fuses is
required. The operating time of the fuses must be below 0.5 seconds.
• Where allowed by local regulations, suitably dimensioned type B MCB circuit breakers
of equivalent rating must be utilized in place of fuses, providing that the clearing
capacity is sufficient for the installation.
• Transient surge suppression shall be installed on the line side of this equipment and
shall be rated 600 V (phase to ground), 600 V (phase to phase), suitable for
overvoltage category III, and shall provide protection for a rated impulse withstand
voltage peak of 2.7 kV.
Requirements on cables
• For compliance with CE and C Tick EMC requirements, a symmetrical shielded cable
is recommended.
• Ensure that all control conductors are twisted together until they reach the connection
point. Make sure that they stay twisted together after the cable has been peeled at the
connection point.
• To avoid coupling to other interference sources, place the control conductors in a
separate cable channel in the control panel.
• Separate signal and protective ground (earth) from each other. The two ground
(earth) connections must be connected together at the main supply point since
parallel ground (earth) is not allowed.
• If ground loops, current, or magnetic disturbances occur in the cable screen, then
open the cable screen connection in the control panel and connect a capacitor in
series between the cable screen and ground, for example, 0.5 μf, 1 kV.
• The ground (earth) system must have one system ground (earth), where all ground
(earth) connections are connected from the control panel and various control units.
Avoid ground (earth) loops through gland plates and cable gland bonding and
ensure that there is no potential difference in the ground (earth) system.
• Monitor cables must be isolated from all mains cables by at least 30 cm (11.8 in) by
use of separate metal conduits and/or grounded (earthed) cable trays.
• Monitor cables must be isolated from all motor cables by at least 50 cm (19.7 in) by
use of separate metal conduits and/or grounded (earthed) cable trays.
• Monitor cables must not cross power cables unless necessary, and then only at
90 degree angles.
Grounding guidelines
Protective earth conductor
The cross sectional area of the protective earth conductor must be at least equal to that of
the incoming supply conductor.
Ground fault monitoring
If an ELCB (Earth Leakage Circuit Breaker) is used, then the following conditions apply:
• A type B device must be used
• The device must be suitable for protecting equipment with a DC component in the
leakage current
• An individual ELCB should be used for each drive
Shield or cable screen termination
Use a shield terminating or EMI clamp to connect the shield to the safety ground terminal.
Electrical Installation
SRC 311 - SmartRun
™
Installation, Operation, and Maintenance Manual
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