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SPECIFICATIONS & PERFORMANCE
SYSTEM CLASSIFICATION
Type of protection against electric shocks: This instrument is classified as Class I equipment.
Class I equipment does not depend only on basic insulation for protection against electric shocks, but
also provides a means of connection to a protective earth system of facilities so that metal parts that
come into contact do not become conductive while the basic insulation is in failure.
Degree of protection against harmful ingress of water: IPx0
The PC-50S has no protection against ingress of water. (The degree of protection against harmful
ingress of water defined in IEC 60529 is IPx0.)
Classification according to the method(s) of sterilization or disinfection recommended by the
manufacturer: not applicable.
The PC-50S has no part to be sterilized or be disinfected.
Classification according to the degree of safety of application in the presence of a flammable
anesthetic mixture with air or with oxygen or nitrous oxide:
Equipment not suitable for use in the presence of a flammable anesthetic mixture with air or with
oxygen or nitrous oxide.
The PC-50S should be used in environments where no flammable anesthetics and/or flammable gases
are present.
Classification according to the mode of operation: Continuous operation.
Continuous operation is the operation under normal load for an unlimited period, without the specified
limits of temperature being exceeded.
CONVERSION OF TEST DISTANCE (REFERENCE)
The following formula is provided to calculate the visual acuity when the instrument performs a test at
the shorter distance than the set value.
Converted visual acuity = Visual acuity (selected) × Test distance (real value)/Test distance (set
value) ----- (1)
or
Test distance (real value) = Test distance (set value) × Converted visual acuity/Visual acuity
(selected) ----- (2)
Example 1)
When the test distance is set to "5m" and the "0.03" visual acuity chart is used, the patient sees the
chart at the real test distance 2.5m. The visual acuity is calculated by the formula of (1) as shown
below.
Converted visual acuity = 0.03 x 2.5/5 = 0.015
The converted visual acuity is 0.015.
Example 2)
The inspector wants to perform the test of the visual acuity 0.01 by setting the test distance "6m" and
using the chart of visual acuity "0.03". The necessary test distance is calculated by the formula of (2)
as shown below.
Test distance = 6 x 0.01/0.03 = 2
The inspector can perform the test at the real test distance "2m".