Emerson Fisher FIELDVUEDVC2000, Fisher FIELDVUEDVC6200 Instruction Manual

Instruction Manual

D102796X012

Fisherr HF340 Filter

HF340 Filter

March 2015

This instruction manual includes installation and
maintenance information for the HF340 HARTr filter
(see figure 1). Refer to separate manuals for additional
information on other products used with the HART
filters, such as FIELDVUEt DVC6200, DVC6000, or
DVC2000 digital valve controllers.

Control system refers to a distributed control system
(DCS), programmable logic controller (PLC), or a
stand‐alone controller that provides a control signal to
the FIELDVUE instrument.

Do not install, operate, or maintain an HF340 filter
without being fully trained and qualified in valve,
actuator, and accessory installation, operation, and
maintenance. To avoid personal injury or property

damage, it is important to carefully read, understand,
and follow all of the contents of this manual, including
all safety cautions and warnings. If you have any

questions about these instructions contact your

Emerson Process Management sales office

before

proceeding.

Figure 1. Fisher HF340 HART Filter

FIELD INSTRUMENT
CONNECTIONS (FLD)

HART COMMUNICATION
CONNECTIONS
(COMM)

CONTROL SYSTEM
CONNECTIONS
(SYS)

W8283-1

Description

The HF340 filter is used with HART communicating FIELDVUE instruments, such as DVC6200, DVC6000, or DVC2000
digital valve controllers. HART filters are used when the instrument is connected to a 4 to 20 mA DC control system
output not designed for the HART (Highway Addressable Remote Transducer) communication protocol. The HF340
provides filtering and isolation between the control system and FIELDVUE instrument.

The HF340 HART filter is a passive device that is inserted in‐line with both wires of a HART 4 to 20 mA DC output loop.
The purpose of the filter is to effectively isolate the control system analog output from modulated HART
communication signals. The filter receives a 4 to 20 mA DC current signal from the control system, which it shunts
with a capacitor and then passes through an inductor. The low AC impedance of the capacitor prevents sudden
changes in the control system current output from interfering with the HART communication. The high AC impedance
of the inductor permits HART communication on the instrument side of the filter. It also prevents the voltage
modulation in the HART loop from being seen by, or having an affect on, the control system output. The filter
introduces a maximum input‐to‐output voltage drop of 2 volts DC at 20 mA.

www.Fisher.com

HF340 Filter

March 2015

Table 1. Specifications

Instruction Manual

D102796X012

Mounting

Standard 35 mm DIN rail mounting with filtering
components.

Electromagnetic Compatibility

Meets EN 61326-1 (First Edition)
Immunity—Industrial locations per Table 2 of
the EN 61326-1 standard. Performance is

Connections

Three 2‐pin cage‐clamp style connectors
accept up to 12 AWG wire

Power Requirements

Input Current: 4-20 mA DC (nominal)
Input Voltage: At 20 milliamps DC, 2 volts above

shown in table below 2.
Emissions—Class A
ISM equipment rating: Group 1, Class A

Dimensions

75 mm (3 inches) long by 12.5 mm (0.5 inches) wide
by 60 mm (2.4 inches) deep

input voltage required by the field instrument (2 volt
drop across filter at 20 milliamps DC)

Approximate Weight

0.1 kg (4 oz)

Ambient Operating Temperature

-40 to 85_C (-40 to 185_F)

Ambient Relative Humidity

5 to 95%

Option

HF341: Standard 35 mm DIN rail mounting without
filtering components (straight through with capacitor
blocking on COMM terminals)

Table 2. EMC Summary Results; Immunity

Port Phenomenon Basic Standard Test Level Performance Criteria

Electrostatic discharge (ESD) IEC 61000‐4‐2

Enclosure

I/O signal/control

A = During testing, normal performance within the specification limits.

1. Not applicable; only applicable to magnetically sensitive equipment.

EM field IEC 61000‐4‐3

Rated power frequency
magnetic field

Burst IEC 61000‐4‐4 1 kV A
Surge IEC 61000‐4‐5 1 kV (line to ground only, each) A
Conducted RF IEC 61000‐4‐6 150 kHz to 80 MHz at 3 Vrms A

IEC 61000‐4‐8 N/A

4 kV contact
8 kV air

80 to 100 MHz @ 10V/m with 1 kHz at 80%
1400 to 2000 MHz @ 3V/m with 1 kHz at 80%
2000 to 2700 MHz @ 1V/m with 1 kHz at 80%

(1)

N/A

A

A

(1)

The filter is normally installed near the field wiring terminals of the control system I/O. HART communication is only
possible between the filter and the field instrument and at the filter COMM terminals, but not on the control system
side of the filter. The filter is not designed or intended for use in the process environment. Neither the filter nor its
outputs are approved for hazardous areas. However, a recommended intrinsic safety barrier can be connected
between the FIELDVUE instrument and the filter in intrinsically safe installations. In most cases, if an IS barrier is used,
the filter will not be needed.

Specifications

Typical specifications for the HF340 filter are shown in table 1.

2