Masoneilan SVI II AP Installation and Maintenance ... - GE Energy

GE Oil and Gas
SVI II AP Instruction Manual
CAUTION
Do not connect a HART modem and PC to a control circuit
unless the controller is HART compatible or has a HART filter.
Loss of control or a process upset may occur if the controller
output circuit is not compatible with HART signals.
Install in compliance with Hazardous Area rules in
accordance with local electrical codes and plant standards by
trained specialists.
Do not connect a PC or HART modem to an intrinsically safe
circuit except on the safe area side of the barrier. Do not
operate a PC in a hazardous area without compliance with
local and plant regulations.
NOTE
A control circuit must be HART compatible or have a HART
filter installed. Contact the manufacturers of the controller or
DCS. See “HART Filter Requirements” on page 125.
Wiring Guidelines
Comply with current national and local regulations for
electrical installation work.
Comply with national and local explosive atmosphere
regulations.
Before carrying out any work on the device, power off the
instrument or make sure that the locale conditions for
potentially explosive atmosphere permit the safe opening
of the cover.
This list contains eight guidelines for a successful implementation of DC current signal,
DC power, and HART communication to the SVI II AP:
Compliance voltage at the SVI II AP must be 9 V at the maximum current of 20 mA.
Signal to the SVI II AP must be a well-regulated current in the range 3.8 to 22 mA.
Controller output circuit must be unaffected by the HART tones which are in the
frequency range between 1200 and 2200 Hz.
Frequency range of the HART tones must have a circuit impedance of more than
220 Ohms, typically 250 Ohms.
HART tones may be imposed by the positioner and a communication device
located anywhere on the signaling circuit.
Capacitance of the signaling circuit may 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 the
HART tones, with the shield grounded at only one location.
Signal must be properly grounded in only one place.
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