No. 2A201-519EN*A
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If the above actions cannot be performed, the following emergency measures can be
performed.
•
Change the sensitivity current.
•
Set the time before operation of the alarm so that it is longer than the scan time (100
seconds or more).
NOTE:
If the constants of the noise filter, etc. of the CT system are changed, adverse
effects such as EMI noise may result. Therefore, countermeasures cannot be
performed at the CT system.
CAUTION:
Use only noise filters manufactured by Toshiba. The noise filter of this system
is designed taking into account extreme phenomena such as lightning. If a
noise filter made by a manufacturer other than Toshiba is used, the system may
not be protected adequately.
8.1.4 Voltage
regulation
The line voltage fluctuation of the system is ±10%.
If variation exceeds
±
10%, the automatic voltage adjusting unit should be used.
When a power transformer must be installed at any site in an EC country because the site
power conditions do not satisfy the above requirements, SYSTEM TRANSFORMER (model
CETF005C) manufactured by TOSHIBA must be used.
8.1.5
Countermeasures against high-frequency electromagnetic radiation
(1) High-frequency electromagnetic radiation
The original alternating current is in the form of a sine wave, but the input current of an
inverter, etc. is in the form of a wave with step-like distortions. General electric appliances
such as TV sets, personal computers, air-conditioners, etc. generate high-frequency
electromagnetic radiation. Elevators or other motor-driven device can also generate high-
frequency radiation. Since CT systems include an inverter they can be sources of high
frequency radiation.
If the total level of the high frequency radiation becomes excessively high, some units may
become abnormal because resonance occurs in a capacitor or a reactor due to the
adverse effects of wave distortion.
(2) Measures for controlling high-frequency electromagnetic radiation
If excessive high-frequency electromagnetic radiation is generated, take the following
countermeasures.
•
Mount an alternating-current filter for the prevention of high-frequency electromagnetic
radiation to the main power source to reduce high-frequency electromagnetic radiation.
•
Insert alternating-current filters in the distribution panels of the major devices generating
high-frequency electromagnetic radiation to partially reduce the radiation.
Since Toshiba does not handle these filters now, a specialist must be consulted to
determine appropriate countermeasures based on the line capacity and the level of
radiation.