3-6
Installing the Servo Drive
07-01-08-02-E-V0500 631 Digital Servo Drive
When the ac supply is switched on, a pulse of current flows to earth to charge the
internal/external ac supply EMC filter’s internal capacitors which are connected between phase
and earth. This has been minimised in Eurotherm Drives’ filters, but may still trip out any circuit
breaker in the earth system. In addition, high frequency and dc components of earth leakage
currents will flow under normal operating conditions. Under certain fault conditions larger dc
protective earth currents may flow. The protective function of some circuit breakers cannot be
guaranteed under such operating conditions.
WARNING!
Circuit breakers used with VSDs and other similar equipment are not suitable for
personnel protection. Use another means to provide personal safety. Refer to
EN50178 (1998) / VDE0160 (1994) / EN60204-1 (1994)
Wiring the Servo Drive
Earth Connections
WARNING!
Due to the working principle of servo drives or filters, there will be an eart leakage
current exceeding 10mA dc, 3.5mA ac.
IMPORTANT:
Refer to “Earth Fault Monitoring Systems”. page 3-5.
The wiring terminals accept a maximum conductor size of 12 AWG (3.2mm²).
The servo drive, when fitted with an internal ac supply EMC filter, is only suitable for earth
referenced supplies (TN).
Refer to Chapter 12: “Certification for the Servo Drive” for information on earthing
requirements.
DBR1 & DBR2 - External Brake Resistor
Refer to Chapter 13: “Application Notes” - Dynamic Braking for selection details and Chapter
11: “Technical Specifications” - Power Details.
DBR1
DBR2
Top View of 631
Figure 3-3 External Brake Resistor Terminals
Caution
The resistor should be mounted on a heatsink (back panel) and covered to prevent injury
from burning.
