NORD Drivesystems BU0750 - Manual (Page 8)

NORDAC SK 750E Manual
8 Subject to technical amendments BU 0750 GB-3311
1.4 Safety and installationinformation
NORDAC SK 750E frequency inverters are devices for use in industrial high voltage systems and are operated
at voltages which could lead to severe injuries or death if they are touched.

Installation and other work may only be carried out by qualified electricians and with the device
disconnected. The operating instructions must always be available to these persons and must be
strictly observed.

Local regulations for the installation of electrical equipment and accident prevention must be complied
with.

The equipment continues to carry hazardous voltages for up to 5 minutes after being switched off at
the mains. The equipment may only be opened or the cover or control element removed 5 minutes
after the equipment has been disconnected from the power supply. All covers must be put back in
place before the line voltage is switched back on again.

For safe isolation from the mains, all poles of the supply cable to the frequency inverter must be able
to be disconnected.

Even during motor standstill (e.g. caused by a release block, blocked drive or output terminal short
circuit), the line connection terminals, motor terminals and braking resistor terminals may still conduct
hazardous voltages. A motor standstill is not identical to electrical isolation from the mains.

Caution, even parts of the control card and, in particular, the connection plug for the removable
technology units can conduct hazardous voltages. The control terminals are mains voltage free.

Caution, with certain settings, the frequency inverter/motor can start up automatically after the mains
are switched on.

The circuit boards contain highly-sensitive MOS semiconductor components that are particularly
sensitive to static electricity. Avoid touching circuit tracks and components with the hand or metallic
objects. Only the terminal strip screws may be touched with insulated screwdrivers when connecting
the cables.

The frequency inverter is only intended for permanent connection and may not be operated without
effective earthing connections which comply with local regulations for large leakage currents
(> 3.5mA). VDE 0160 stipulates the installation of a second earthing conductor or an earthing
conductor cross-section of at least 10 mm
2
.

In case of three-phase frequency inverters, common ground-fault circuit interrupters are not suitable
only for protection if the local regulations do not permit possible DC components in the leakage
current. The standard FI circuit breaker must comply with the new design as per VDE 0664.

In normal use, NORDAC SK 750E frequency inverters are maintenance free. The cooling surfaces
must be regularly cleaned with compressed air if the ambient air is dusty.
CAUTION
The heat sink and all other metal components can heat up to temperatures above 70°C.
When mounting, sufficient distance from neighbouring components must be maintained.
When working on the components, allow sufficient cooling time before starting work.
ATTENTION
DANGER TO LIFE
The power unit can continue to carry voltages for up to 5 minutes after being switched off at
the mains. Inverter terminals, motor cables and motor terminals may carry voltage!
Touching open or free terminals, cables and equipment components can lead to severe injury
or death!
Work may only be carried out by qualified electricians and with the electrical supply to the
equipment disconnected.