Drive Setup CDHD
76 User Manual
Fuse holders: St andard fuse blocks, or finger-safe fuse holders according
to IEC 60529. For exam ple:
Bussm ann: CH Series modular fuse holders, fuse size 0 to 30A, class J,
3 poles: CH30J3
Ferraz: Ult rasafe fuse holders, fuse size 0 to 30A, class J, 3 poles:
US3J3I
5 .4 .2 Lea k age Cu rrent Con sidera t ion s
Leakage current via the PE conductor results from the combination of equipm ent
and cable leakage currents. The leakage current frequency pattern com prises a
number of frequencies, whereby the residual-current circuit breakers definitively
evaluate the 50 Hz current. For this reason, the leakage current cannot be
measured using a conventional multim eter.
As a rule of thumb, the following assumption can be m ade for leakage current on
cables, depending on the PWM frequency of the output stage:
I leak = n x 20 mA + L x 1 mA/ m at 8 kHz PWM frequency at the output
stage
I leak = n x 20 mA + L x 2 mA/ m at a 16 kHz PWM frequency at the output
stage
( where I leak= leakage current, n= num ber of drives, L= length of motor cable)
Since the leakage current to PE is greater than 3.5 mA, com pliance with
I EC61800-5-1 requires that either the PE connection be doubled or a connecting
cable with a cross-section greater than10 mm² be used. Use the PE terminal and
the PE connection screws to meet this requirement.
5 .4 .3 Residu al Cur rent Prot ect iv e D ev ice ( RCD )
In compliance with standards IEC 60364-4-41 Regulations for Installation and
I EC 60204 Electrical Equipment of Machinery, residual current protective devices
(RCD) can be used provided the requisite regulations are met.
RCDs which are sensitive to all currents m ust be used in order to detect any DC
fault current.
To protect against direct contact (with m otor cables shorter than 5 m), it is
recom mended that each drive be protected individually using a 30 m A RCD,
which is sensitive to all currents.
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