
28
Digidrive SK Technical Data
www.leroy-somer.com Issue Number: a
11 Supply types
Digidrive SK is suitable for use with any supply type, i.e. TN-S, TN-C-S, TT, IT, with a grounding at any potential, i.e. neutral, centre or corner
('grounded-delta').
Drives are suitable for use on supplies of installation category III and lower, according to IEC60664-1. This means they may be connected
permanently to the supply at its origin in a building, but for outdoor installation, additional over-voltage suppression (transient voltage surge
suppression) must be provided to reduce category IV to category III.
11.1 AC supply requirements
Single phase drives
Single phase - Between one phase and neutral of a star connected three phase supply.
- Between two phases of a three phase supply.
Three phase models
Three-phase star or delta supply of the correct voltage.
Dual rated models
Any of the above supplies can be used.
11.2 Safety
11.3 Cables
Recommended cable sizes are given in tables 1-2 & 1-7. They are only a guide; refer to local wiring regulations for correct size of cables. In some
cases, a larger cable size is required to avoid excessive voltage drop.
Use 105
°
C (221
°
F) (UL 60/75
°
C temp rise) PVC-insulated cable with copper conductors having a suitable voltage rating, for the following power
connectors:
•
AC supply to external EMC filter (when used)
•
AC supply (or external EMC filter) to drive
•
Drive to motor
•
Drive to braking resistor
Motor cables
The recommended output cable sizes assume that the motor maximum current matches that of the drive. Where a motor of reduced rating is used,
the cable rating may be chosen to match that of the motor. To ensure that the motor and cable are protected against overload, the drive must be
programmed with the correct motor rated voltage.
Electric shock risk
The voltages present in the following locations can cause severe electric shock and may be lethal:
•
AC supply cables and connections
•
DC and brake cables and connections
•
Output cables and connections
•
Many internal parts of the drive, and external option units
Unless otherwise indicated, control terminals are single insulated and must not be touched.
Isolation device
The AC supply must be disconnected from the drive using an approved isolation device before any cover is removed from the drive or
before any servicing work is performed.
STOP function
The STOP function does not remove dangerous voltages from the drive, the motor or
any external option units.
Stored charge
The drive contains capacitors that remain charged to a potentially lethal voltage after the AC supply has been disconnected. If the drive
has been energized, the AC supply must be isolated at least ten minutes before work may continue.
Normally, the capacitors are discharged by an internal resistor. Under certain, unusual fault conditions, it is possible that the capacitors
may fail to discharge, or be prevented from being discharged by a voltage applied to the output terminals. If the drive has failed in a
manner that causes the display to go blank immediately, it is possible the capacitors will not be discharged. In this case, consult LEROY-
SOMER.
Equipment supplied by plug and socket
Special attention must be given if the drive is installed in equipment which is connected to the AC supply by a plug and socket. The AC
supply terminals of the drive are connected to the internal capacitors through rectifier diodes which are not intended to give safety
isolation. If the plug terminals can be touched when the plug is disconnected from the socket, a means of automatically isolating the plug
from the drive must be used (e.g. a latching relay).
WARNING
WARNING
WARNING
WARNING
WARNING