4-22
4-3 Wiring Conforming to EMC Directives
4
System Design
Selecting Connection Components
This section explains the criteria for selecting the connection components required to improve noise
resistance. Understand each component’s characteristics, such as its capacity, performance, and
applicable conditions when selecting the components. For more details, contact the manufacturers
directly.
No-fuse Breakers (NFB)
When selecting a no-fuse breaker, consider the maximum input current and the inrush current.
Maximum Input Current:
The Servo Drive’s maximum momentary output is approximately three times the rated output, and
can be output for up to three seconds. Therefore, select a no-fuse breaker with an operating time
of at least five seconds at 300% of the rated current. General-purpose and low-speed no-fuse
breakers are generally suitable.
Select a no-fuse-breaker with a rated current greater than the total effective load current of all the
Servomotors. The rated current of the power supply input for each Servomotor is provided in
Add the current consumption of other controllers, and any other components, when selecting the
NFB.
Inrush Current:
The following table lists the Servo Drive inrush currents.
With low-speed no-fuse breakers, an inrush current 10 times the rated current can flow for
0.02 second.
When multiple Servo Drives are turned ON simultaneously, select a no-fuse-breaker with a 20-ms
allowable current that is greater than the total inrush current shown in the following table.
Servo Drive model
Inrush current (A0-p)
Main circuit power supply
R7D-BP Series
20
