Influence Of Static Electricity And Required Countermeasures - Toshiba Aquilion TSX-101A/I Series Site Planning Manual

Cause/route
Entry from cables
exposed to radiation
noise
• Radiation noise from
the cables of the CT
system transfers to the
cables of the
ultrasound system and
enters the system via
the cables.
• Radiation noise from
the cables of the
ultrasound system
transfers to the cables
of the CT system and
enters the system via
the cables.
A.1.2

Influence of static electricity and required countermeasures

(1) What is static electricity?
The Static Electricity Handbook of the Static Electricity Institute (published by Ohm Inc.)
defines static electricity as "electricity where the spatial movement of electric charges is
small and the effects of the magnetic field due to the slight spatial movement of electric
charges are negligible in comparison to the effects of the electric field." That is, static
electricity is electricity which resides in the material and moves little.
To study actual phenomena related to static electricity, however, dynamic electricity
phenomena (for example, static discharge) caused by static electricity phenomena must
be included in the scope of study.
Thus, the study of static electricity phenomena includes the study of some dynamic
electricity phenomena. It should be noted that the voltages involved in static electricity
phenomena are generally higher in comparison to those involved dynamic electricity
phenomena, but the total amount of electricity (electric charge) involved is generally much
less for static electricity phenomena than for dynamic electricity phenomena.
Cause/route
identification procedure
Check whether the cables of the
ultrasound system and the
optional units are close to the
cables of the CT system.
If they are close, change the
cable routing to increase the
distance between the sets of
cables and check whether the
noise is reduced.
Perform simple shielding of the
cables of the ultrasound system
using aluminum foil and ground
the cables and then check
whether the noise is reduced.
Change the cable routing to increase the
distance between the cables.
Shield the cables using a mesh type of
shielding material.
65
No. 2A201-519EN*A
Countermeasures