App. A Advantageous Use Of Inverters (Notes On Electrical Noise); Effect Of Inverters On Other Devices - Fuji Electric FRENIC-HVAC User Manual

App. A Advantageous Use of Inverters (Notes on electrical
noise)
- Disclaimer: This document provides you with a summary of the Technical Document of the
Japan Electrical Manufacturers' Association (JEMA) (April 1994). It is intended to apply to
the domestic market only. It is only for reference for the foreign market. -
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Effect of inverters on other devices

Inverters have been and are rapidly expanding its application fields. This paper
describes the effect that inverters have on electronic devices already installed or on
devices installed in the same system as inverters, as well as introducing noise
prevention measures. (Refer to Section A.3 [3], "Noise prevention examples" for details.)
[ 1 ] Effect on AM radios
Phenomenon
Probable cause
Measures
[ 2 ] Effect on telephones
Phenomenon
Probable cause
Measures
[ 3 ] Effect on proximity switches
Phenomenon
Probable cause
Measures
[ 4 ] Effect on pressure sensors
Phenomenon
Probable cause
Measures
[ 5 ] Effect on position detectors (pulse encoders)
Phenomenon
Probable cause

App. A Advantageous Use of Inverters (Notes on electrical noise)

If an inverter operates, AM radios may pick up noise radiated from
the inverter. (An inverter has almost no effect on FM radios or
television sets.)
Radios may receive noise radiated from the inverter.
Inserting a noise filter on the power supply side of the inverter is
effective.
If an inverter operates, nearby telephones may pick up noise radiated
from the inverter in conversation so that it may be difficult to hear.
A high-frequency leakage current radiated from the inverter and
motors enters shielded telephone cables, causing noise.
It is effective to commonly connect the grounding terminals of the
motors and return the common grounding line to the grounding
terminal of the inverter.
If an inverter operates, proximity switches (capacitance-type) may
malfunction.
The capacitance-type proximity switches may provide inferior noise
immunity.
It is effective to connect a filter to the input terminals of the inverter
or change the power supply treatment of the proximity switches. The
proximity switches can be replaced with superior noise immunity
types such as magnetic types.
If an inverter operates, pressure sensors may malfunction.
Noise may penetrate through a grounding wire into the signal line.
It is effective to install a noise filter on the power supply side of the
inverter or to change the wiring.
If an inverter operates, pulse encoders may produce erroneous pulses
that shift the stop position of a machine.
Erroneous pulses are liable to occur when the signal lines of the PG
and power lines are bundled together.
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