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Welch Allyn SureSight Autorefractor - User Manual User Manual

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Electromagnetic Immunity

The SureSight is intended for use in the electromagnetic environment specified below. The
customer or the user of the SureSight should assure that it is used in such an environment.
Immunity test

IEC 60601
test level

Compliance
level

Electromagnetic environment –
guidance

Conducted RF
IEC 61000-4-6

Radiated RF
IEC 61000-4-3

3 Vrms
150 kHz to 80
MHz

3 V/m
80 MHz to 2.5
GHz

NA*

3 V/m

Portable and mobile RF
communications equipment should
be used no closer to any part of the
SureSight, including cables, than the
recommended separation distance
calculated from the equation
applicable to the frequency of the
transmitter.

Recommended separation
distance

d = (1.17 )

d = (1.17)

80 MHz to 800 MHz

d = (2.33)

800 MHz to 2.5 GHz

where P is the maximum output
power rating of the transmitter in
watts (W) according to the
transmitter manufacturer and d is
the recommended separation
distance in meters (m).

Field strengths from fixed RF
transmitters, as determined by an

electromagnetic site survey,

a

should be less than the compliance

level in each frequency range.

b

Interference may occur in the
vicinity of equipment marked with
the following symbol:

NOTE 1

At 80 MHz and 800 MHz, the higher frequency range applies.

NOTE 2

These guidelines may not apply in all situations. Electromagnetic propagation is affected by
absorption and reflection from structures, objects and people.