Sanyo KMS2472, KMS1872 Noise Malfunction and Electromagnetic Interference, Noise malfunction

8-5. Noise Malfunction and Electromagnetic Interference

An inverter A/C operates using pulse signal control and high frequencies. Therefore, it is susceptible to the effects of external noise, and is likely to cause electromagnetic interference with nearby wireless devices.

A noise filter is installed for ordinary use, preventing these problems. However, depending on the installation conditions, these effects may still occur. Please pay attention to the points listed below.

(1) Noise malfunction

This refers to the application of high-frequency noise to the signal wires, resulting in abnormal signal pulses and malfunction.

Locations most susceptible to noise	Trouble	Correction
1.Locations near broadcast stations where	Either of the following trouble may occur.	(The fundamental concept is to
there are strong electromagnetic waves	1.The unit may stop suddenly during	make the system less susceptible to noise.)
		- Insulate for noise or
2.Locations near amateur radio (short wave)	operation.
stations	2.Indicator lamps may flicker.	distance from the noise source. -
3.Locations near electronic sewing machines		1.Use shielded wires.
and arc-welding machines		2.Move unit away from the noise source.

(2) Electromagnetic interference

This refers to noise generated by high-speed switching of the microcomputer and compressor. This noise radiates through space and returns to the electric wiring, affecting any wireless devices (televisions, radios, etc.) located nearby.

Locations most susceptible to noise	Trouble	Correction
1.A television or radio is located near the	1.Noise appears in the television picture,	1.Select a separate power source.
A/C and A/C wiring.	or the picture is distorted.	2.Keep the A/C and A/C wiring at least 1 meter
2.The antenna cable for a television or	2.Static occurs in the radio sound.	away from wireless devices and antenna cables.
radio is located close to the A/C and A/C		3.Change the wireless device’s antenna to a high-
wiring.
		sensitivity antenna.
3.Locations where television and radio
		4.Change the antenna cable to a BS coaxial cable.
signals are weak.
		5.Use a noise filter (for the wireless device).
		6.Use a signal booster.

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