Electra WNG 50 DCI Service Manual page 95

14.4.9 Checking the communication
Change to Stand-by or Power OFF and re-start - If the fault is still "Active" check Indoor
to Outdoor Communication wiring and grounding connections (should be less than 2.0Ω)
– Repair if needed.
If IDU failure – replace IDU controller that does not respond.
If ODU failure – replace ODU.
14.4.10 Checking for electromagnetic interferance (EMC problems)
14.4.10.1 EMC troubles to the A/C uni
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.
14.4.10.2 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.
Service Manual - WNG 50_60_80 DCI
t
Revision Y05-02
CONTENT
TROUBLESHOOTING
14-9