Emerson Process Management Specifications -GENERAL for Model 3081 pH/ORP, Intrinsic Safety

MODEL 3081 pH/ORP

1.3SPECIFICATIONS -GENERAL FOR MODEL 3081 pH/ORP

Case: Cast aluminum containing less than 8% magnesium. NEMA 4X (IP65), NEMA 7 (explosion-proof) Epoxy-polyester paint, Neoprene O-ring seals

Dimensions: 6.3 in. x 6.9 in. x 6.4 in. (160 mm x 175 mm x 161 mm); diameter 6.1 in (155 mm)

Conduit Openings: 3/4 in. FNPT

Reference Impedance: Transmitter accepts high impedance (i.e. glass) reference electrodes as well as low impedance (i.e. silver-silver chloride) reference electrodes.

Output: Two-wire 4-20 mA output with superimposed HART digital signal.

Output can be programmed to go to any value between 3.8 and 22.0 mA to indicate a fault or hold condition.

Response Time: Display reaches 95% of final reading within 10 seconds.

Temperature Sensors: The following RTDs can be used with the Model 3081 pH/ORP transmitter:

3 and 4 wire Pt 100 RTDs

3 and 4 wire Pt 1000 RTDs

3000 ohm Balco RTD

Transmitter can also be used with two-wire RTDs. Temperature Range: 5°F to 248°F (-15°C to 120°C)

Local Display: Two line LCD; first line shows process vari- able (pH or ORP), second line shows temperature and output signal. When triggered, fault and warning mes- sages alternate with temperature and output readings.

Process variable: 7 segment LCD, 0.8 in. (20 mm) high

Temperature/output: 7 segment LCD, 0.3 in. (7 mm) high

Display board can be rotated 90 degrees clockwise or counterclockwise.

During calibration and programming, messages and prompts appear in the temperature/output area.

Power Supply and Load Requirements: See graph below. A minimum loop resistance of 250 Ω and a minimum power supply voltage of 18 Vdc is required for HART communication. Maximum power supply voltage for intrinsically safe and explosion-proof operation is 42.4 Vdc.

SECTION 1.0

DESCRIPTION AND SPECIFICATIONS

Security: User selected security code prevents accidental changes to program settings.

Ambient Temperature: -4 to 149°F (-20 to 65°C)

Relative Humidity: 0 to 95% (with covers sealed)

Storage Temperature: -22 to 176°F (-30 to 80°C)

EMI/RFI: Meets the requirements of EN50081-1

EN50081-2

Hazardous Area Classification:

Explosion Proof:

FM:	Class I, Div. 1, Groups B, C & D
	Class II, Div. 1, Groups E, F, & G
	Class III, Div. 1
CSA:	Class I, Div. 1, Groups C& D
	Class I, Div. 2, Groups A, B, C & D
	Class II, Div. 2, Groups E, F & G
	Class III, Div. 1
Intrinsic Safety:
FM:	Class I, II & III, Div. 1
	T4 T AMB= 40°C; T3AT AMB= 70°C
CSA:	Class I, Div. 1

T 3C T AMB=40°C; T3 T AMB=80°C CENELEC: EEx ia IIC

T5 Tamb=40°C; T4 Tamb=65°C

Non-Incendive:

FM: Class I, Div. 2, Groups A, B, C & D

CSA: Class I, Div. 2, Groups A, B, C & D T5 (Tamb=40°C)

Weight/Shipping Weight: 10 lb/10 lb (4.5 kg/4.5 kg).

Weights and shipping weights are rounded to the nearest whole pound.

minimum voltage and load for HART communication

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