3.3.15 High Voltage Test
Carry out a high voltage test by short-circuiting terminals
U, V, W, L1, L2 and L3. Energize by max. 2.15 kV DC for
one second between this short-circuit and the chassis.
NOTE
When running high voltage tests of the entire installation,
frequency converter and compressor electrical motor
compressor test can be conducted together.
WARNING
When conducting a high voltage test make sure the
system is not under vacuum: this may cause electrical
motor compressor failure.
WARNING
Never apply the high voltage test to the control circuit.
3.4 Fuses and Circuit Breakers
3.4.1 Fuses
NOTE
Use fuses and/or circuit breakers on the supply side of the
unit for protection of electrical components within the
frequency converter 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
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 provide UL branch
circuit protection.
Danfoss recommends using the fuses/circuit breakers listed
below to protect service personnel and property in case of
component break-down in the frequency converter.
3.4.2 Recommendations
WARNING
In case of malfunction, ignoring recommended fuse types
may result in personnel risk and damage to the frequency
converter and other equipment.
The following tables list the recommended rated current.
Recommended fuses are of the type gG for small to
medium power sizes. For larger powers, aR fuses are
recommended. For circuit breakers, Moeller types have
been tested to have a recommendation. Other types of
circuit breakers may be used provide they limit the energy
into the to a level equal to or lower than the Moeller
types.
For further information, see Application Note
Fuses and
Circuit Breakers, MN90T
How to Install
Operating Instructions VLT
®
CDS302 and CDS303
MG34M302 - VLT
®
is a registered Danfoss trademark/Commercial Compressor
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