SIEMENS
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Siemens IK PI · 2015
PROFIBUS
Electrical networks (PROFIBUS PA)
Active field distributors
3
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Technical specifications
Active field distributor (AFD)
General data
Connection of field devices
• Standard-compliant field devices
for PROFIBUS PA or FOUNDATION
Fieldbus H1
• Max. 4 per AFD4
• Max. 8 per AFD8
• Max. 31 per fieldbus segment
•
Operating environment up to Zone
2
oder 22; Class I Zone 2/ Division 2
• The max. current consumption of all
fieldbus components of the fieldbus
segment is 1 A
Degree of protection
IP66
Voltages, currents, potentials
Power supply
Via bus, no auxiliary power necessary
Rated supply voltage, permissible
range
16 ... 32 V DC
Reverse polarity protection
(together with FDC 157)
Yes
Overvoltage protection
No
Current consumption
• Current consumption at idle
AFD4: 24 mA
AFD8: 34 mA
• Current consumption with
connected field devices
AFD4: 24 mA
+ total current of all field devices
AFD8: 34 mA
+ total current of all field devices
• Additional current consumption of
the AFD at end of line
(an open main line connection)
30 mA
• Current consumption at
max. power output per spur line
AFD4: 264 mA
AFD8: 514 mA
Power loss
AFD4: Min. 384 mW; max. 3.2 W
AFD8: Min. 544 mW; max. 4.1 W
Grounding
Direct, via grounding rail
Electrical isolation between
main line and spur lines
No
Connections, interfaces
Main line
Number of connections
2
Interfaces
PROFIBUS PA and
FOUNDATION Fieldbus H1
Automatic bus terminator
Yes
Spur cables
Number of connections
• AFD4
4
• AFD8
8
Short-circuit-proof
Yes
Intrinsically-safe acc. to FISCO
No
Current I
max
(DC) on spur lines
1 to 4 (AFD4) or 1 to 8 (AFD8)
60 mA
Short-circuit current (test current)
6 mA
Debounce logic
Yes
No-load voltage
< 30 V
Current output to field devices
• AFD4
Max. 240 mA
• AFD8
Max. 480 mA
Status, interrupts, diagnostics
Status indicator
Yes
Diagnostics function
Yes
Diagnostics LED
Yes
Interrupts
No
Climatic conditions
Permissible operating temperature
-40 ... +70 °C
Permissible storage/transport
temperature
-40 ... +85 °C
Relative humidity during operation
Max. 95 %
Approvals for potentially explosive
atmospheres
• Gas
Zone 2
• Dust
Zone 22
Dimensions and weight
Dimensions (W x H x D) in mm
(without fittings)
• AFD4
220 x 120 x 83
• AFD8
360 x 120 x 83
Weight
• AFD4
2 000 g
• AFD8
3 000 g
Active field distributor (AFD)
© Siemens AG 2014