Badger Meter SRD/SRI Valve Positioners - Manual (Page 75)

HART measured at
configurator: measured at
SRD:
Configurator
transmits at least
350 mVpp
at least
120 mVpp
SRD991
transmits at least
120 mVpp
at least
400 mVpp
FoxCom Communication
When using the ‘communication’ (a rectangular signal which is modulated onto the constant current signal), make sure the
connected outputs are suitable for the used frequency ranges The supply instrument must be a voltage source with an
impedance of 250…500 Ohm The total of all instrument and lead capacities must be <60 nF It is recommended therefore, to
use only suitable instruments
To eliminate crosstalk between leads and to reduce disturbances through electromagnetic influences, use twisted paired
shielded leads (0 3…2 5 mm 2 , max 100 pF/m)
The capacities of the leads and the connected instruments must not exceed the maximum values for FoxCom
All components which are connected to the SRD in an explosion hazardous area, require an Ex-Approval The applicable
limit values must not be exceeded in any case These limit values also have to be adhered to when connecting additional
capacitances, inductances, voltages and currents
Measuring FoxCom Communication Signal
If a reliable communication signal cannot be received, it is advisable to check the level with an oscilloscope The first data
block always comes from the configurator and the second block is the reply from the SRD
FOXCOM measured at
configurator: measured at
SRD:
Configurator trans-
mits (Request) at least
350 mVpp
at least
75 mVpp
SRD transmits
(Acknowledge) at least
75 mVpp
at least
350 mVpp
With Communication PROFIBUS-PA
The operation of the positioner takes place digitally, as per PROFIBUS-PA Profile Class B according to EN 50170 and DIN
19245 part 4 Data transmission via bit synchronous current modulation with a speed of 31250 bits via twisted and
shielded two-wire connections according to IEC 1158-2, with cable shields on both sides and bus terminators according to
recommendation IEC 1158-2
The positioner has to be connected to a segment coupler, which has to be conforming to IEC 1158-2 For operation in
explosion hazardous areas, a segment coupler in explosion proof version has to be used Supply as well as communication
takes place via the bus
All components which are connected to the SRD in an explosion hazardous area, require an Ex-Approval The applicable
limit values must not be exceeded in any event These limit values also have to be adhered to when connecting additional
capacitances, inductances, voltages and currents The FISCO model is thereby used as a basis
Further information for observance:
”Technical Guide for PROFIBUS-Connection Technique” PROFIBUS-User Organization, Order no 2 141
With Communication FOUNDATION Fieldbus
The operation of the positioner takes place digitally, as per FOUNDATION Fieldbus Specification Rev 1 4 Data transmission via
bit synchronous current modulation with a speed of 31250 bits of via twisted and shielded two-wire connections according to
IEC 1158-2, with cable shields on both sides and bus terminators according to recommendation IEC 1158-2
The positioner has to be connected to components which are conforming to IEC 1158-2 For operation in explosion hazardous
areas, an Ex-separator has to be used Supply as well as communication takes place via the bus
System Configuration
Page 75 August 2014 POS-UM-00010-EN-03