Version No. V5R0
3
9202 Pulse Isolator
Safety Manual
3. Purpose of the product
Pulse isolator for transmission of signals to the safe area from NAMUR sensors
and mechanical switches installed in the hazardous area.
The module can be mounted in the safe area and in zone 2 / div. 2 and receive
signals from zone 0, 1, 2, 20, 21 and 22 / Class I/II/III, Div. 1, Gr. A-G.
Error events, including cable breakage, are monitored and signalled via the
individual status relay and/or a collective electronic signal via the power rail.
The 9202 has been designed, developed and certified for use in SIL 2 applications
according to the requirements of IEC 61508.
4. assumptions and restrictions for use of the product
4.1 Basic safety specifications
Operational temperature range ............ -20...+60°C
Storage temperature range .................. -20...+85°C
Power supply type, min. ....................... Double or reinforced
Supply voltage ...................................... 19.2...31.2 VDC
Output pulse length, min. ..................... 40
m
s
Mounting area ....................................... Zone 2 / Division 2 or safe area
Mounting environment .......................... Pollution degree 2 or better
4.2 associated equipment
4.2.1 relay output
The relay output shall only be connected to equiment which has
a current limiting function of 2 A.
4.2.2 opto output
The opto output signals are fed to SIL 2 compliant inputs of a
safety PLC specified to receive a frequency of 5 kHz and a pulse
length down to 40 microseconds or the field device signal pulse
length minus 60 microseconds.
4.2.3 field device
The field device must provide a minimum pulse length of 100
microseconds.
4.3 failure rates
The basic failure rates from the Siemens standard SN 29500 are used
as the failure rate database.
Failure rates are constant, wear-out mechanisms are not included.
External power supply failure rates are not included.
