Ublox SARA-N210, Руководство по системной интеграции

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SARA-N2 series - System Integration Manual
UBX-17005143 - R06 Design-in Page 55 of 82
Protection against polarity reversal
Protection against polarity reversal shall be provided within intrinsically safe apparatus to prevent
invalidation of the type of protection as a result of reversal of the polarity of supplies to that
intrinsically safe apparatus or at connections between cells of a battery where this could occur. For
this purpose, single diode shall be acceptable.
Other considerations
All the recommendations reported in section 2.11.1 must be considered for the implementation of the
VCC supply circuit on application integrating SARA-N211 modules intended for use in potentially
explosive atmospheres. Any specific applicable requirement for the VCC supply circuit design must
be fulfilled according to all the exact applicable standards for the apparatus.
☞
Check the detailed requisites on the pertinent norms for the application apparatus, as for example
the IEC 60079-0
[15] , IEC 60079-11 [16] , IEC 60079-26 [17] standards.
2.11.3 Guidelines for antenna RF interface design
The RF radiating power of SARA-N211 modules is compliant to all the applicable 3GPP / ETSI
standards, with a maximum of 250 mW RF average power according to the LTE Cat NB1 Power Class
stated in
Table 2 .
The RF threshold power of the application device integrating a SARA-N211 module is defined,
according to the IEC 60079-0 ATEX standard
[15] , as the product of the effective output power of the
module multiplied by the antenna gain (implemented/used on the application device).
The RF threshold power of the application device integrating a SARA-N211 module must not exceed
the limits shown in
Table 26 , according to the IEC 60079-0 ATEX standard [15] .
Gas group II subdivision RF threshold power limits according to the IEC 60079-0 ATEX standard
IIA (a typical gas is propane) 6.0 W
IIB (a typical gas is ethylene) 3.5 W
IIC (a typical gas is hydrogen) 2.0 W
Table 26: RF threshold power limits for the different gas group II subdivisions according to the IEC 60079-0 ATEX standard [15]
☞
The system antenna(s) implemented/used on the application device integrating SARA-N211
module must be designed/selected so that the antenna gain (i.e. the combined transmission line,
connector, cable losses and radiating element gain) multiplied by the output power of the module
does not exceed the limits shown in
Table 26 .