8.4 Installing Peripheral Devices
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YASKAWA ELECTRIC
SIEP C710606 44B YASKAWA AC Drive T1000V Technical Manual
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Connecting a Surge Absorber
A surge absorber suppresses surge voltage generated from switching an inductive load near the drive. Inductive loads
include magnetic contactors, relays, valves, solenoids and brakes. Always use a surge absorber or diode when operating
with an inductive load.
Note:
Never connect a surge absorber to the drive output.
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Connecting a Noise Filter
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Reducing Radiated, Conducted, and Induced Noise
Drives generate noise that can potentially affect surrounding devices like PLCs, etc.
•
Radiated Noise:
Electromagnetic waves noise throughout the radio bandwidth radiated from the drive and cables.
•
Conducted Noise:
Noise generated by the drive and emitted to through the power lines.
•
Induced Noise:
Noise generated by electromagnetic induction can affect control signal lines.
Take the following measurements to prevent noise causing malfunction of other drives or devices:
• Install all components on a well grounded metal plate.
• Keep the motor cable as short as possible.
• Use noise filters on the input side of the drive to reduce conducted noise.
• Install noise filters on the input and output side of the drive, install the drive in a metal enclosure panel and use a
shielded motor cable to reduce radiated noise.
• Use shielded motor and control circuit lines and lay control circuit lines at least 30 cm away from power lines in order
to prevent malfunction due to induced noise.
Figure 8.5
Figure 8.5 Reducing Radio Frequency Noise
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Input-Side Noise Filter
Drive outputs generate noise as a result of high-speed switching. This noise flows from inside the drive back to the power
supply, possibly affecting other equipment. Installing a noise filter to the input side of the drive can reduce the amount of
noise flowing back into the power supply. This also prevents noise from entering the drive from the power supply.
• Use a noise filter specifically designed for AC drives.
• Install the noise filter as close as possible to the drive.
A – Metal enclosure
F – Shielded motor cable
B – Power supply
G – Motor
C – Input noise filter
H – Separate at least 30 cm
D – Drive
I – Control signal lines
E – Output noise filter
J – Controller
J
I
H
C
E
D
B
F
A
R/L1
MCCB
S/L2
T/L3
U/T1
V/T2
W/T3
M
G