Parker BD-E Series, Manual

Page: 27 / 48

SECTION 3. INSTALLATION 21
Earth leakage current
The AC supply to the BD-E drive is internally filtered to achieve EMC compliance. The filter
components create an earth leakage current of the order of 10mA, which is compatible with
standard residual-current breakers operating at 30mA. The BD-E drive is not suitable for use on
supplies employing high-sensitivity RCD breakers.
Motor safety earth connection
It is essential that there is a safety earth connection to the motor housing. A separate earth lead
must therefore be taken from the earth terminal on the motor, routed with the motor and encoder
leads and terminated at the safety earth stud on the side of the BD-E. The motor earth terminal
is located between the motor and encoder sockets. The safety earth lead should be at least
2.5mm
2
in area.
Control signal connections - BD-E
The analogue input signal should be carried in a twisted-pair screened cable with the screen
connected to the connector shell on the drive and to the appropriate ground on the controller.
The encoder output signals should be similarly carried in twisted-pair screened cable.
Using an External Positioner
The incremental encoder incorporated in the motor may be used to provide position information
to an external positioner. Terminals 10-15 on the User I/O connector provide the true and
complementary signals from all three encoder channels (see Table 3-3). These outputs are
generated by 26LS31 line drivers.
Note: Particular care should be paid to these outputs to prevent EMC radiation problems. When
using line receivers - connect the screen to earth at both ends of the cable. In this configuration
the drive and controller should be mounted close together sharing the same ground plane.
For opto receivers - connect the screen to earth at the drive end only.