Welch Allyn Scale-Tronix 4802D Mode D'emploi page 32

28 Appendices
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.
a
Field strengths from fixed transmitters, such as base stations for radio (cellular/cordless) telephones and land mobile
radios, amateur radio, AM and FM radio broadcast, and TV broadcast cannot be predicted theoretically with accuracy. To
assess the electromagnetic environment due to fixed RF transmitters, an electromagnetic site survey should be
considered. If the measured field strength in the location in which the Welch Allyn Pediatric/Infant Scale is used
exceeds the applicable RF compliance level above, the Welch Allyn Pediatric/Infant Scale should be observed to verify
normal operation. If abnormal performance is observed, additional measures may be necessary, such as reorienting or
relocating the Welch Allyn Pediatric/Infant Scale.
b
Over the frequency range 150 kHz to 80 MHz, field strengths should be less than 3 V/m.
Recommended separation distances between portable and mobile RF communications
equipment and the Welch Allyn Pediatric/Infant Scale
The Welch Allyn Pediatric/Infant Scale is intended for use in an electromagnetic environment in which radiated RF
disturbances are controlled. The customer or user of the Welch Allyn Pediatric/Infant Scale can help prevent
electromagnetic interference by maintaining a minimum distance between portable and mobile RF communications
equipment (transmitters) and the Welch Allyn Pediatric/Infant Scale as recommended below, according to the maximum
output power of the communications equipment.
Rated max. output
power of transmitter
(W)
0.01
0.1
1
10
100
For transmitters rated at a maximum output power not listed above, the recommended separation distance d in meters
(m) can be estimated using the equation applicable to the frequency of the transmitter, where P is the maximum output
power rating of the transmitter in watts (W) according to the transmitter manufacturer.
Note 1: At 80 MHz and 800 MHz, the separation distance for the higher frequency range applies.
Electromagnetic immunity
430 MHz to 470 MHz 430 MHz to 470 MHz
800 MHz to 960 MHz 800 MHz to 960 MHz
1700 MHz to 1990 1700 MHz to 1990
MHz MHz
2400 MHz to 2570 2400 MHz to 2570
MHz MHz
9 V/m 9 V/m
704 MHz to 787 MHz 704 MHz to 787 MHz
5100 MHz to 5800 5100 MHz to 5800
MHz MHz
Separation distance according to frequency of transmitter (m)
150 kHz to 80 MHz 80 MHz to 800 MHz
d= (1.17) d= (1.17)
0.12 0.12
0.37 0.37
1.20 1.20
3.70 3.70
12 12
Welch Allyn Pediatric/Infant Scale
800 MHz to 2.7 GHz
d= (2.33)
0.23
0.74
2.30
7.40
23