Download active field distributors

ACTIVE FIELD DISTRIBUTORS
Active field distributor AFD
The active field distributor (AFD) can be operated in environments in accordance with Ex
zone 2/22. It can integrate up to 4 PA (PROFIBUS PA) or FF (FOUNDATION Fieldbus H1) field devices via shortcircuit-proof spur line connections into a fieldbus segment (line/ring) with automatic bus termination. This fieldbus
segment can be connected to a single or redundant PROFIBUS DP via a PA or FF router and it can thus be seamlessly
integrated into the SIMATIC PCS 7 process control system.
Up to 8 active field distributors AFD with a total of up to 31 connected field devices can be operated per fieldbus
segment. The number of field devices is also limited by the current consumption of the field devices. A current of 1 A
is available for all field devices of a segment.
An AFD in a ring segment can be replaced during operation without failure of the segment.
For compliance with IP65 protection, it is necessary to protect unused spur line connections by plugs.
Page 1977
Mar 2008
Siemens ITS
Active field distributor AFDiS
The active field distributor AFDiS (Active Field Distributor intrinsic Safety) can be operated in environments in
accordance with Ex zone 1/21 and 2/22. It can integrate up to 6 intrinsically-safe PA (PROFIBUS PA) or FF
(FOUNDATION Fieldbus H1) field devices into a fieldbus segment (line/ring) via its intrinsically-safe, short-circuitproof spur line connections. Instead of the spur line, it is also possible to use a subsegment for 3 to 4 devices
Page 1978
Mar 2008
Siemens ITS
with a max. length of 500 m at connection S1 of the AFDiS. The spur lines with type of protection Ex [ia] as well as
the subsegment can be routed into Zone 0/20.
Up to 5 field distributors AFDiS with a total of up to 31 field devices can be operated in a fieldbus segment. The
limitation to 5 field distributors is also mandatory for mixed operation of AFD and AFDiS.
The number of field devices per segment additionally depends on the current consumption of the devices. A current of
1 A is available for all field devices of the segment.
With the integrated repeater function, the AFDiS has the following advantages compared to the AFD:


Spur line lengths are independent of the total number of spur lines in the bus segment
Spur line lengths need not be be taken into account when determining the total length of the bus segment
Under the following conditions, an AFDiS in a ring segment can be replaced during operation without failure of the
segment: Installation in zone 2/22; no mixed operation with AFD.
For compliance with IP66 protection, it is necessary to protect unused spur line connections by plugs.
Active field splitter AFS
The active field splitter (AFS) connects a PA or FF line segment with a redundant coupler pair of a PA or FF router.
The AFS interconnects the line segment with the respective active coupler.
To guarantee IP65 protection, it is necessary to protect an unused connection by a plug.
Technical specifications
Page 1979
Mar 2008
Siemens ITS
Technical specifications
Active field distributor (AFD)
General data
Connection of field devices
Degree of protection
Voltages, currents, potentials
Rated supply voltage
Voltage Vmax
Reverse polarity protection
Internal power consumption
Current
per spur line X1 to X4
PageImax
1980
•Standard-compliant field devices for
PROFIBUS PA or FOUNDATION Fieldbus H1
•Max. 4 per AFD
•Max. 31 per fieldbus segment
•Operating environment up to zone 2 or 22
•The max. current consumption of all field
devices of the fieldbus segment is 1 A
IP65
16 V DC (16 ... 32 V)
35 V
Yes
Max. 25 mA or 59 mA with AFD at end of cable
(open main line connection)
60 mA
Mar 2008
Siemens ITS
Status, interrupts, diagnostics
Diagnostic displays:
•Status main line PA1, PA2
•Fault main line PA1, PA2
•Status/fault spur line X1 to X4
Climatic conditions
Permissible operating temperature
Dimensions and weight
Dimensions (W x H x D) in mm
Weight
Active field distributor AFDiS
General data
Connection of field devices
Degree of protection
Voltages, currents, potentials
Power
supply
Page
1981
Green LED
Red LED
Green LED
-25 ... +70 °C
175 x 57 x 105;
with screw gland 175 x 57 x 105
Approx. 700 g
•Standard-compliant field devices for
PROFIBUS PA or FOUNDATION Fieldbus H1
•Max. 6 per AFD
•Max. 31 per fieldbus segment
•Operating environment up to zone 1 or 21
•The max. current consumption of all field
devices of the fieldbus segment is 1 A
IP66
Via bus,
Mar 2008
no auxiliary power necessary
Siemens ITS
Rated supply voltage, permissible range
Polarity reversal protection (only in connection
with DP/PA coupler)
Overvoltage protection
Current consumption
•At 28 V input voltage
•At 24 V input voltage
•At 20 V input voltage
Power loss
Grounding
Electrical isolation between main line and spur
lines
Test voltage
Connections, interfaces
Main line
Number of connections
Interfaces
Automatic bus terminator
Spur cables
Number
connections
Pageof
1982
16 ... 32 V DC
Yes; up to 1 A
No
≤ 64 mA + (0.838 * aggregate current of all the
field devices)
≤ 67 mA + (1.008 * aggregate current of all the
field devices)
≤ 74 mA + (1.246 * aggregate current of all the
field devices)
Min. 1.4 W; max. 5.9 W
Direct, via connecting bar
Yes
2 550 V DC, 2 s
2
PROFIBUS PA and FOUNDATION Fieldbus
H1
Yes
6
Mar 2008
Siemens ITS
Short-circuit-proof
Intrinsically-safe acc. to FISCO
Current Imax on spur line S1
Current Imax on spur lines S2 to S6
Current Imax in total for all field devices
Short-circuit current (test current)
Debounce logic
No-load voltage
Current output to field devices
Status, interrupts, diagnostics
Status display
Diagnostics function
Diagnostic indicator LED
Climatic conditions
Permissible operating temperature
Permissible storage/transport temperature
Relative humidity during operation
Approvals for potentially explosive
atmospheres
•Gas
•Dust
Dimensions and weight
Dimensions (W x H x D) in mm
Weight
Page 1983
Yes
Yes
60 mA
40 mA
180 mA
5 mA
Yes
Max. 15.3 V
Max. 260 mA
Yes
Yes
Yes
-40 ... +70 °C
-40 ... +85 °C
Max. 95 %
Zone 1 and Zone 2
Zone 21 and Zone 22
380 x 85 x 170
4 500 g
Mar approx.
2008
Siemens ITS
Active field splitter AFS
General data
Connection of field devices
•Max. 31 per fieldbus segment
•Operating environment up to zone 2 or 22
•The max. current consumption of all field
devices of the fieldbus segment is 1 A
IP65
Degree of protection
Voltages, currents, potentials
Rated supply voltage
16 V DC (16 ... 32 V)
Reverse polarity protection
Yes
Overvoltage protection
Yes
Voltage failure bridging
5 ms
Current consumption
≤ 25 mA
Power loss
Max. 1 W
Output current for supplying all field devices of 1 A
the fieldbus segment (for dimensioning the
device configuration)
Status, interrupts, diagnostics
Diagnostic displays:
•Status main line PA1, PA2
Green LED
•Fault main line PA1, PA2
Red LED
Climatic conditions
Permissible operating temperature
-25 ... +70 °C
Dimensions
and weight
Mar 2008
Page 1984
Siemens ITS