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Illustration 3.6 Motor and Mains Connection with Service Switch
For both small and large unit, the service switch is
optional. The switch is shown mounted on the motor side.
Alternatively, the switch can be located on the mains side,
or omitted.
For the large unit, the circuit breaker is optional. The large
unit can be configured with either service switch or circuit
breaker, not both.
is not configurable in
practice, but is displayed to show the respective positions
of components only.
Usually the power cables for mains are unscreened cables.
3.2.1.3 Relay Connection
To set relay output, see parameter group 5-4* Relays.
No.
01-02
make (normally open)
01-03
break (normally closed)
04-05
make (normally open)
04-06
break (normally closed)
Table 3.3 Relay Settings
For location of relay terminals, refer to
FCD 302 Operating
Instructions, MG04F
.
3.2.2 Fuses and Circuit Breakers
3.2.2.1 Fuses
Fuses and/or circuit breakers are recommended protection
on the supply side, in the event of component break-down
inside the frequency converter (first fault).
NOTE
This is mandatory in order to ensure compliance with IEC
60364 for CE or NEC 2009 for UL.
WARNING
Personnel and property must be protected against the
consequence of component break-down internally in the
frequency converter.
Branch Circuit Protection
In order to protect the installation against electrical and
fire hazard, all branch circuits in an installation, switch
gear, machines etc., must be protected against short-circuit
and over-current according to national/international
regulations.
NOTE
The recommendations given do not cover Branch circuit
protection for UL.
Short-circuit protection
Danfoss recommends using the fuses/circuit breakers
mentioned below to protect service personnel and
property in case of component break-down in the
frequency converter.
3.2.2.2 Recommendations
WARNING
In the event of malfunction, failure to follow the
recommendation may result in personnel risk and damage
to the frequency converter and other equipment.
The following sections list the recommended rated current.
Danfoss recommends fuse type gG and Danfoss CB
(Danfoss - CTI-25) circuit breakers. Other types of circuit
breaker may be used provide they limit the energy into
the frequency converter to a level equal to or lower than
the Danfoss CB types.
Follow the recommendations for fuses and circuit breakers
to ensure any damage to the frequency converter is
internal only.
For further information see Application Note
Fuses and
Circuit Breakers, MN90T
.
System Integration
VLT
®
Decentral Drive FCD 302
30
MG04H102 - VLT
®
is a registered Danfoss trademark
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