Power Filter - Fuji Electric Alpha7 VV User Manual

CHAPTER 10 PERIPHERAL EQUIPMENT

10.6 Power Filter

The servo amplifier performs high frequency switching under PWM control similarly to
general-purpose inverters. Therefore radiant noise, conductive noise and so on may give effect on
peripheral equipment.
The following method is effective as a countermeasure.
(1) House the servo amplifier in an iron (conductive) control panel and ground the control panel.
Do not install a PC or measuring instrument nearby.
(2) If devices connected to the same power supply are affected, install a power filter in the primary
circuit of the servo amplifier.
If devices in different power supplies are affected, install an obstruction wave preventive
10
transformer (TRAFY).
(3) Route cables between the servo amplifier and servomotor in a conductive duct and ground the
duct (multi-point grounding allowed).
(4) Use a grounding cable as thick and short as possible.
Connect the grounding cable directly from the copper bar to individual device (do not use a
jumper cable). A twisted or net cable has a larger effect.
(5) Never connect the following signals.
Grounding terminal
FG (Frame ground)
(6) Do not tie the main circuit cable and control circuit cable together. Do not route these cables in
parallel.
Main circuit: Commercial power supply, motor power cable between servo amplifier and
servomotor
Control circuit: +24 [V] DC or less voltage signal cable
Servomotor encoder cable
(7) Use an obstruction wave preventive transformer (TRAFY) to connect 100 [V] devices (such as
the programmable logic controller and general-purpose PC) to the 200 [V] power supply.
10-12
Power Filter
Power transformer
Power
supply
Conductive
noise
0 [V] of +24 [V] DC power
supply for sequence I/O
Radiant noise
Servo amplifier
Static induction
Electromagnetic induction noise
noise
Measuring
instrument
Electronic
device
Radio
Servomotor
M
Sensor
0 [V] of encoder power
supply