Watson-Marlow MM420 - Manual (Page 28)

2 Installation Issue 10/06
MICROMASTER 420 Operating Instructions
28 6SE6400-5AA00-0BP0
2.4.1 General
WARNING
The inverter must always be grounded . If the inverter is not grounded correctly,
extremely dangerous conditions may arise within the inverter, which could prove
potentially fatal.
Operation with ungrounded (IT) supplies
Filtered
It is not permissible to connect MICROMASTER 4 drive converters equipped with
integrated filter
to non-grounded line supplies.
Unfiltered
If connected to non-grounded line supplies, the 'Y' capacitor must be disabled in
the device. The procedure is described in Attachment B.2.
If the MICROMASTER is to remain in operation in non-grounded networks when a
ground fault occurs during the input or output phase, an output reactor must be
installed.
Operation with Residual Current Device
If an RCD (also referred to as ELCB or RCCB) is fitted, the MICROMASTER
inverters will operate without nuisance tripping, provided that:
A type B RCD is used.
The trip limit of the RCD is 300mA.
The neutral of the supply is grounded.
Only one inverter is supplied from each RCD.
The output cables are less than 50m (screened) or 100m (unscreened).
NOTE
The residual current operated circuit-breakers used must provide protection against
direct-current components in the fault current and must be suitable for briefly
suppressing power pulse current peaks. It is recommended to protect the
frequency inverter by fuse separately.
The regulations of the individual country
(e.g. VDE regulations in Germany)
and the regional power suppliers must be observed!