Electra LEX 25 DCI Service Manual page 102

13.2.5.10 Checking for electromagnetic interferance (EMC problems)
EMC troubles to the A/C unit
Locations most susceptible to noise :
1. Locations near broadcast stations where there are strong electromagnetic waves.
2. Locations near amateur radio (short wave) stations.
3. Locations near electronic sewing machines and arc-welding machines.
Trouble :
Either of the following trouble may occur:
1. The unit may stop suddenly during operation.
2. Indicator lamps may flicker
Correction :
The fundamental concept is to make the system less susceptible to noise
(insulate for noise or distance from the noise source):
1. Use shielded wires.
2. Move unit away from the noise source.
13.2.5.11 EMC troubles to near by home appliances
Locations most susceptible to noise :
1. A television or radio is located near the A/C and A/C wiring.
2. The antenna cable for a television or radio is located close to the A/C and A/C wiring.
3. Locations where television and radio signals are weak.
Trouble :
1. Noise appears in the television picture, or the picture is distorted.
2. Static occurs in the radio sound.
Correction
1. Select a separate power source.
2. Keep the A/C and A/C wiring at least 1 meter away from wireless devices and antenna
cables.
3. Change the wireless device's antenna to a high sensitivity antenna.
4. Change the antenna cable to a BS coaxial cable.
5. Use a noise filter (for the wireless device).
6. Use a signal booster.
13.2.6
Precaution, Advise and Notice Items
13.2.6.1 High voltage in Outdoor unit controller
Whole controller, including the wires, connected to the Outdoor unit controller may have the potential
hazard voltage when power is on. Touching the Outdoor unit controller may cause an electrical
shock.
Advise: Don't touch the naked lead wire and don't insert finger, conductor or anything else into the
controller when power is on.
13.2.6.2 Charged Capacitors
Three large-capacity electrolytic capacitors are used in the Outdoor unit controller. Therefore,
charging voltage (380VDC) remains after power down. Discharging takes about one minute after
turned off. Touching the Outdoor unit controller before discharging may cause an electrical shock.
When open the Outdoor unit controller cover, don't touch the soldering pin by hand or by any
conductive material.
SM LEXDCI 1-E.1 GB
CONTENTS
TROUBLESHOOTING
13-19