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Fisherr 646 Electro-Pneumatic Transducer

The Fisher 646 electro-pneumatic transducer uses a

converter module that converts a 4 to 20 milliampere

input signal to a proportional 0.2 to 1.0 bar (3 to

15 psig) pneumatic output signal. The converter

module uses small parts of minimum mass, which are

balanced symmetrically around a pivot point at the

center of the mass. This balanced arrangement results

in a high performance instrument that reduces

sensitivity to vibration.

An integral pneumatic relay provides the high capacity

necessary to drive pneumatic control valve/acutator

assemblies without additional boosters or positioners.

The transducer also provides stable, accurate

operation when its output is transmitted to small

volume chambers, such as a pneumatic positioner or

other pneumatic instrument. Reduced sensitivity to

vibration combined with high capacity and first order

lag characteristics make the 646 transducer ideal for

direct mounting on control valve/actuator

combinations.

Connectors and piping can be installed with each 646

transducer for diagnostic testing.

FISHER 646 ELECTRO-PNEUMATIC TRANSDUCER

WITH FISHER 657 ACTUATOR AND E VALVE

FISHER 646 ELECTRO-PNEUMATIC TRANSDUCER

W4908-1

W6783-1

646 Transducer

D101374X012

Product Bulletin

62.1:646

February 2015

Summary of content (8 pages)

PAGE 1
Product Bulletin 646 Transducer 62.1:646 February 2015 D101374X012 Fisherr 646 Electro-Pneumatic Transducer The Fisher 646 electro-pneumatic transducer uses a converter module that converts a 4 to 20 milliampere input signal to a proportional 0.2 to 1.0 bar (3 to 15 psig) pneumatic output signal. The converter module uses small parts of minimum mass, which are balanced symmetrically around a pivot point at the center of the mass.
PAGE 2
Product Bulletin 646 Transducer 62.1:646 February 2015 D101374X012 Specifications Electromagnetic Compatibility: Meets EN 61326-1 (First Edition) Immunity—Industrial locations per Table 2 of the EN 61326-1 standard. Performance is shown in table 1 below.
PAGE 3
Product Bulletin 646 Transducer 62.1:646 February 2015 D101374X012 Specifications (continued) Adjustments Zero and Span: Trim potentiometers (20 turn) for zero and span adjustments are located under the housing cap Mounting Position Any position is acceptable for standard pipestand, panel, or actuator mounting. For weatherproof housing, mount the transducer to allow the vent to drain.
PAGE 4
Product Bulletin 646 Transducer 62.1:646 February 2015 Features D101374X012 Figure 2. Output-Time Relationships n Small Size—The small size and light-weight design of the transducer facilitate mounting and provide improved space utilization. 100 OUTPUT standard valve/actuator mounted application, exhibits an output shift of less than 1 percent of span when tested to SAMA Standard PMC 31.1, Condition 3.
PAGE 5
Product Bulletin 646 Transducer 62.1:646 February 2015 D101374X012 Figure 3. Dimensions 152.4 (6.00) CAP REMOVAL CLEARANCE 152.4 (6.00) 79.2 (3.12) 47.8 (1.88) 35 (1.38) 57 (2.25) 41.1 (1.62) 127.0 (5.00) 102.1 (4.02) FISHER 67CFR 1/4-18 NPT SUPPLY CONN 72.8 (2.86) 9.7 (0.38) 1/4-18 NPT OUTPUT CONN 1/2-14 NPT OR OPTIONAL M20 CONDUIT CONN CENTERLINE OF ACTUATOR 6.4 (0.25) 106.4 (4.19) 127.0 (5.00) OPTIONAL GAUGE 62.0 (2.44) 9.5 1/4-18 NPT (0.
PAGE 6
Product Bulletin 646 Transducer 62.1:646 February 2015 D101374X012 Table 2. Hazardous Area Classifications—CSA (Canada) Certification Body CSA Certification Obtained Intrinsically Safe Ex ia IIC T4/T5 per drawing GE28591 Ex ia Intrinsically Safe Class I, II, Division 1 GP A,B,C,D,E,F,G T4/T5 per drawing GE28591 Explosion-proof Ex d IIC T6 Class I, Division I, GP A,B,C,D T6 Type n Entity Rating Vmax = 30 VDC Imax = 150 mA Pi = 1.
PAGE 7
Product Bulletin 646 Transducer 62.1:646 February 2015 D101374X012 Table 5. Hazardous Area Classifications—IECEx Certificate Certification Obtained Intrinsically Safe Gas Ex ia IIC T4/T5 Ga IECEx Flameproof Gas Ex d IIC T6 Gb Type n Gas Ex nA IIC T6 Gc Entity Rating Ui = 30 VDC Ii = 150 mA Pi = 1.
PAGE 8
Product Bulletin 62.1:646 February 2015 646 Transducer D101374X012 Neither Emerson, Emerson Process Management, nor any of their affiliated entities assumes responsibility for the selection, use or maintenance of any product. Responsibility for proper selection, use, and maintenance of any product remains solely with the purchaser and end user. Fisher is a mark owned by one of the companies in the Emerson Process Management business unit of Emerson Electric Co.