Hart® Wiring Guidelines - GE Masoneilan SVI II ESD Installation And Maintenance Manual

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HART Wiring Guidelines
The following list contains eight guidelines for a successful implementation of DC current
signal, DC power, and HART
Compliance voltage at the SVI II ESD must be 9 V at the maximum current of 20 mA.
Signal to the SVI II ESD must be a well-regulated current in the range of 3.8 to 22 mA.
Controller output circuit must be unaffected by the HART
frequency range between 1200 and 2200 Hz.
Frequency range of the HART
Ohms, typically 250 Ohms.
HART
anywhere on the signaling circuit.
Capacitance of the signaling circuit can not exceed about 0.26 microfarads or with
high series resistance 0.10 microfarads.
Cabling must be shielded to prevent electrical noise that would interfere with HART
tones, with grounded shield at only one location.
Position Retransmit: when wiring this feature:
Wire using the same gauge wire as for the 4-20 mA control loop.
In general, ensure that it is connected to the control system's analog systems card.
Ensure the control loop is powered when using a meter to make any
measurements.
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communication to the SVI II ESD:
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tones can be imposed by the positioner to a communication device located
For details and calculation methods for wiring resistance, and
NOTE
capacitance and for calculation of cable characteristics refer to
the HART
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tones must have a circuit impedance of more than 220
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FSK Physical Layer Specification.
Masoneilan SVI II ESD Installation and Maintenance Manual
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tones which are in the
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