Input Signal

4-20 mA DC, field adjustable split ranging.

Equivalent Circuit

See figure 5

Output Signal

Standard Performance: ■0.2 to 1.0 bar (3 to 15 psi). Rangeability between 0.1 to 1.2 bar (1 and 18 psi)
Multirange Performance: ■0 to 1.2 bar (0 to 18 psi), ■0.4 to 2.0 bar (6 to 30 psi), and ■0 to 2.3 bar (0 to 33 psi) nominal ranges. Actual rangeability available between 0.03 to 2.3 bar (0.5 and 33 psi)
Action: ■Direct (increasing input signal increases transducer output) (Minimum span,
6 psi) or ■Reverse (increasing input signal decreases transducer output) (Minimum span,
11 psi)

Supply Pressure

Standard Performance: 1.2 to 1.6 bar
(18 to 24 psi)
Multirange Performance:
Minimum: 0.2 bar (3 psi) [0.14 bar (2 psi) for a 2.3 bar (33 psi) output] greater than the maximum calibrated output pressure.
Maximum: 2.4 bar (35 psi)

Medium: Air or natural gas
Air Quality: Supply pressure must be clean, dry air that meets the requirements of ISA Standard 7.0.01. A maximum 40 micrometer particle size in the air system is acceptable. Further filtration down to 5 micrometer particle size is recommended. Lubricant content is not to exceed 1 ppm weight (w/w) or volume (v/v) basis. Condensation in the air supply should be minimized.
Natural Gas: Natural gas must be clean, dry, oil-free, and noncorrosive. H2S content should not exceed 20 ppm. Natural gas as the supply medium is only approved for CSA and FM approvals, as specified in tables 2 and 3. Type 846 is not recommended for use with aromatic gas.

Steady-State Air Consumption(1)

0.3 normal m3/hr (12 scfh) at 1.4 bar (20 psi) supply pressure.

Output Air Capacity(1)

Standard Performance: 6.4 normal m3/hr (240 scfh) at 1.4 bar (20 psi) supply pressure.
Multirange Performance: 9.7 normal m3/hr (360 scfh) at 2.5 bar (35 psi) supply pressure

Temperature Limits

Operating: -40 to 85°C (-40 to 185°F).
Storage: -40 to 93°C (-40 to 200°F).

Humidity Limits

0-100% condensing relative humidity.

Performance(2)

Linearity, Hysteresis, and Repeatability: ±0.3% of span.
Temperature Effect (total effect including zero and span): ±0.07%/°C (0.045%/°F) of span
Vibration Effect: ±0.3% of span per g during the following conditions:
5-15 Hz at 4 mm constant displacement
15-150 Hz at 2 g. 150-2000 Hz at 1 g.
per SAMA Standard PMC 31.1, Sec. 5.3, Condition 3, Steady State.
Shock Effect: ±0.5% of span, when tested per SAMA Standard PMC 31.1, Sec. 5.4.
Supply Pressure Effect: Negligible
Electromagnetic Interference (EMI): Tested per IEC 61326-1 (Edition 1.1). Meets emission levels for Class A equipment (industrial locations) and Class B equipment (domestic locations). Meets immunity requirements for industrial locations (Table A.1). Immunity performance is shown in table 1.
Leak Sensitivity: Less than 1.0% of span for up to 4.8 normal m3/hr (180 scfh) downstream leakage.
Overpressure Effect: Less than 0.25% of span for misapplication of up to 7.0 bar (100 psi) supply pressure for less than 5 minutes to the input port.
Reverse Polarity Protection: No damage occurs from reversal of normal supply current (4-20 mA) or from misapplication of up to 100 mA.

Connections

Supply and Output Pressure: 1/4-18 NPT internal connection.
Electrical: 1/2-14 NPT internal conduit connection.

Adjustments

Zero and Span: Screwdriver adjustments located in terminal compartment.

Remote Pressure Reading (optional)

ON or OFF; jumper selectable
Frequency Range: 5,000-8,000 Hz.
Amplitude: 0.4-1.0 Vp-p

Required Operating Voltage

Min. 6.0 V (at 4 mA)
Max. 7.2 V (at 20 mA)
with Remote Pressure Reading ON
Min. 6.4 V (at 4 mA)
Max. 8.2 V (at 20 mA)

Electrical Classification

Hazardous Area

Intrinsic Safety, Flameproof, and Div. 2

Intrinsic Safety, Flameproof and
Dust-Ignition Proof

Intrinsic Safety, Flameproof and Type n

Intrinsic Safety, Flameproof and Type n

Intrinsic Safety, Flameproof and Type n
Refer to tables 2, 3, 4, 5, and 6 for additional information.
Electrical Housing: NEMA 4X, CSA Enclosure Type 4X, IP66 per IEC60529, Tropicalization (Fungus test per MIL-STD-810)

Construction Materials

Housing: ■Low-copper aluminum with polyurethane paint, or ■ 316 stainless steel
O-Rings: Nitrile, except silicone for sensor O-rings.

Mounting

■Actuator, ■pipestand, or ■surface

Weight

Aluminum: 2.9 kg (6.5 lb) excluding options
Stainless Steel: 6.7 kg (14.8 lb) excluding options

Options

■67CFR filter regulator, ■supply and output gauges, ■remote pressure reading, or ■stainless steel mounting bracket

• Vibration Resistant—The low-mass pilot stage, mechanically damped deflector bar, and rugged construction provide stable performance in vibration.
• Large Diameter Nozzles—Large diameter nozzles, free-flow pilot stage design, and large internal pneumatic supply passages provide excellent tolerance to reducing the effects of contaminant buildup and erosion.
• Increased Accuracy, Reduced Sensitivity to Supply Pressure Variations and Downstream Leakage—The electronic feedback control network monitors the pneumatic output signal, detects any input-output deviations and corrects them. This provides very high accuracy and allows the transducer to sense changes in the final element condition and rapidly optimize its air delivery.
• Easy Maintenance—Major mechanical and electrical components are incorporated into a single field-replaceable ``master module" (figure 3). The transducer does not have to be removed from its mounting to facilitate troubleshooting or service. A separate field wiring compartment eases installation and maintenance.
• Quick Diagnostic Checks and Remote Performance Monitoring—With Stroke Port, a constant bleed from the pilot stage vents through a hole in the module cover. Covering the hole increases the transducer output to confirm the proper operation of the pilot and booster stages and stroke the actuator. With optional Remote Pressure Reading, a frequency directly proportional to the output pressure is superimposed on the input signal wires.

Using a 275 HART® Communicator or frequency counter, an operator can monitor the Type 846 output pressure.

Note
Neither Emerson, Emerson Process Management, nor any of their affiliated entities assumes responsibility for the selection, use, or maintenance of any product. Responsibility for the selection, use, and maintenance of any product remains with the purchaser and end-user.