Rosemount 5081 Reference Manual

Reference Manual

00809-0100-3581, Rev AC

October 2019

Rosemount™ 5081

Explosion Proof, Single-Input Intelligent Transmitter

Essential instructions

Read this page before proceeding!

Emerson designs, manufactures, and tests its products to meet many national and international standards. Because these instruments are sophisticated technical products, you must properly install, use, and maintain them to ensure they continue to operate within their normal specifications. The following instructions must be adhered to and integrated into your safety program when installing, using, and maintaining Emerson products. Failure to follow the proper instructions may cause any one of the following situations to occur: loss of life, personal injury, property damage, damage to this instrument, and warranty invalidation.

•Read all instructions prior to installing, operating, and servicing the product.

•If this Reference Manual is not the correct one, call 1-800-854-8257 or 949-757-8500 to request the correct Reference Manual. Save this Reference Manual for future reference.

•If you do not understand any of the instructions, contact your Emerson representative for clarification.

•Follow all warnings, cautions, and instructions marked on and supplied with the product.

•Inform and educate your personnel in the proper installation, operation, and maintenance of the product.

•Install equipment as specified in the installation instructions of the appropriate Reference Manual and per applicable local and national codes. Connect all products to the proper electrical and pressure sources.

•To ensure proper performance, use qualified personnel to install, operate, update, program, and maintain the product.

•When replacement parts are required, ensure that qualified people use replacement parts specified by Emerson. Unauthorized parts and procedures can affect the product's performance, place the safe operation of your process at risk, and VOID YOUR WARRANTY. Look-alike substitutions may result in fire, electrical hazards, or improper operation.

•Ensure that all equipment doors are closed and protective covers are in place, except when maintenance is being performed by qualified people, to prevent electrical shock and personal injury.

WARNING

Physical access

Unauthorized personnel may potentially cause significant damage to and/or misconfiguration of end users’ equipment. This could be intentional or unintentional and needs to be protected against.

Physical security is an important part of any security program and fundamental to protecting your system. Restrict physical access by unauthorized personnel to protect end users’ assets. This is true for all systems used within the facility.

Notice

ROSEMOUNT (“SELLER”) SHALL NOT BE LIABLE FOR TECHNICAL OR EDITORIAL ERRORS IN THIS MANUAL OR OMISSIONS FROM THIS MANUAL. SELLER MAKES NO WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, WITH RESPECT TO THIS MANUAL AND, IN NO EVENT, SHALL SELLER BE LIABLE FOR ANY SPECIAL OR CONSEQUENTIAL DAMAGES INCLUDING, BUT NOT LIMITED TO, LOSS OF PRODUCTION, LOSS OF PROFITS, ETC.

PRODUCT NAMES USED HEREIN ARE FOR MANUFACTURER OR SUPPLIER IDENTIFICATION ONLY AND MAY BE TRADEMARKS/ REGISTERED TRADEMARKS OF THESE COMPANIES.

THE CONTENTS OF THIS PUBLICATION ARE PRESENTED FOR INFORMATIONAL PURPOSES ONLY, AND WHILE EVERY EFFORT HAS BEEN MADE TO ENSURE THEIR ACCURACY, THEY ARE NOT TO BE CONSTRUED AS WARRANTIES OR GUARANTEES, EXPRESSED OR IMPLIED, REGARDING THE PRODUCTS OR SERVICES DESCRIBED HEREIN OR THEIR USE OR APPLICABILITY. WE RESERVE THE RIGHT TO MODIFY OR IMPROVE THE DESIGNS OR SPECIFICATIONS OF SUCH PRODUCTS AT ANY TIME.

SELLER DOES NOT ASSUME RESPONSIBILITY FOR THE SELECTION, USE, OR MAINTENANCE OF ANY PRODUCT. RESPONSIBILITY FOR PROPER SELECTION, USE, AND MAINTENANCE OF ANY SELLER PRODUCT REMAINS SOLELY WITH THE PURCHASER AND END-USER.

Warranty

1.LIMITED WARRANTY: Subject to the limitations contained in Section 2 herein and except as otherwise expressly provided herein, Rosemount (“Seller”) warrants that the firmware will execute the programming instructions provided by Seller and that the Goods manufactured or Services provided by Seller will be free from defects in materials or workmanship under normal use and care until the expiration of the applicable warranty period. Goods are warranted for twelve (12) months from the date of initial installation or eighteen (18) months from the date of shipment by Seller, whichever period expires first. Consumables and Services are warranted for a period of 90 days from the date of shipment or completion of the Services. Products purchased by Seller from a third party for resale to Buyer (“Resale Products”) shall carry only the

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warranty extended by the original manufacturer. Buyer agrees that Seller has no liability for Resale Products beyond making a reasonable commercial effort to arrange for procurement and shipping of the Resale Products. If Buyer discovers any warranty defects and notifies Seller thereof in writing during the applicable warranty period, Seller shall, at its option, promptly correct any errors that are found by Seller in the firmware or Services, or repair or replace F.O.B. point of manufacture that portion of the Goods or firmware found by Seller to be defective, or refund the purchase price of the defective portion of the Goods/Services. All replacements or repairs necessitated by inadequate maintenance, normal wear and usage, unsuitable power sources, unsuitable environmental conditions, accident, misuse, improper installation, modification, repair, storage or handling, or any other cause not the fault of Seller are not covered by this limited warranty, and shall be at Buyer's expense. Seller shall not be obligated to pay any costs or charges incurred by Buyer or any other party except as may be agreed upon in writing in advance by an authorized Seller representative. All costs of dismantling, reinstallation and freight, and the time and expenses of Seller's personnel for site travel and diagnosis under this warranty clause shall be borne by Buyer unless accepted in writing by Seller. Goods repaired and parts replaced during the warranty period shall be in warranty for the remainder of the original warranty period or ninety (90) days, whichever is longer. This limited warranty is the only warranty made by Seller and can be amended only in a writing signed by an authorized representative of Seller. Except as otherwise expressly provided in the Agreement, THERE ARE NO REPRESENTATIONS OR WARRANTIES OF ANY KIND, EXPRESSED OR IMPLIED, AS TO MERCHANTABILITY, FITNESS FOR PARTICULAR PURPOSE, OR ANY OTHER MATTER WITH RESPECT TO ANY OF THE GOODS OR SERVICES. It is understood that corrosion or erosion of materials is not covered by our guarantee.

2.LIMITATION OF REMEDY AND LIABILITY: SELLER SHALL NOT BE LIABLE FOR DAMAGES CAUSED BY DELAY IN PERFORMANCE. THE SOLE AND EXCLUSIVE REMEDY FOR BREACH OF WARRANTY HEREUNDER SHALL BE LIMITED TO REPAIR, CORRECTION, REPLACEMENT, OR REFUND OF PURCHASE PRICE UNDER THE LIMITED WARRANTY CLAUSE IN SECTION 1 HEREIN. IN NO EVENT, REGARDLESS OF THE FORM OF THE CLAIM OR CAUSE OF ACTION (WHETHER BASED IN CONTRACT, INFRINGEMENT, NEGLIGENCE, STRICT LIABILITY, OTHER TORT, OR OTHERWISE), SHALL SELLER'S LIABILITY TO BUYER AND/OR ITS CUSTOMERS EXCEED THE PRICE TO BUYER OF THE SPECIFIC GOODS MANUFACTURED OR SERVICES PROVIDED BY SELLER GIVING RISE TO THE CLAIM OR CAUSE OF ACTION. BUYER AGREES THAT IN NO EVENT SHALL SELLER'S LIABILITY TO BUYER AND/OR ITS CUSTOMERS EXTEND TO INCLUDE INCIDENTAL, CONSEQUENTIAL OR PUNITIVE DAMAGES. THE TERM “CONSEQUENTIAL DAMAGES” SHALL INCLUDE, BUT NOT BE LIMITED TO, LOSS OF ANTICIPATED PROFITS, LOSS OF USE, LOSS OF REVENUE, AND COST OF CAPITAL.

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4

Reference Manual	Contents
00809-0100-3581	October 2019

Contents

Chapter 1	Start-up.........................................................................................................................		7
Chapter 2	Description and specifications........................................................................................		9
	2.1	Features and applications.................................................................................................................	9
	2.2	General specifications.......................................................................................................................	9
	2.3	Rosemount 5081 - (A/P/C/T) product certifications........................................................................	12
	2.4	Functional specifications................................................................................................................	15
	2.5	Ordering information.....................................................................................................................	17

Chapter 3	Install...........................................................................................................................		19
	3.1	Unpack and inspect........................................................................................................................	19
	3.2	Installation guidelines.....................................................................................................................	19
	3.3	Orient the display board.................................................................................................................	20
	3.4	Mount on a flat surface...................................................................................................................	21
	3.5	Mount on a pipe.............................................................................................................................	22

Chapter 4	Wire............................................................................................................................		25
	4.1	Wiring overview.............................................................................................................................	25
	4.2	Power supply/current loop.............................................................................................................	25
Chapter 5	Display and operate.....................................................................................................		29
	5.1	User interface and main display......................................................................................................	29
	5.2	Infrared remote control (IRC)..........................................................................................................	30
	5.3	Menu system..................................................................................................................................	31
Chapter 6	Programming basics....................................................................................................		43
	6.1	Programming.................................................................................................................................	43
	6.2	Test 4-20 mA outputs and current generated during hold and faults..............................................	43
	6.3	Correct temperature......................................................................................................................	45
	6.4	Set up a custom curve (conductivity measurements only)..............................................................	46
	6.5	Restore to factory default settings..................................................................................................	47
	6.6	Set access (security) code...............................................................................................................	47
	6.7	Activate or deactivate HOLD...........................................................................................................	48
Chapter 7	Measurements.............................................................................................................		49
	7.1	Calibrating pH sensors....................................................................................................................	49
	7.2	Calibrating oxidation reduction potential (ORP) sensors.................................................................	52
	7.3	Calibrating contacting and toroidal conductivity sensors................................................................	54
	7.4	Calibrating dissolved oxygen, ozone, free chlorine, total chlorine, and ozone sensors....................	56
Chapter 8	Diagnostics and troubleshooting..................................................................................		61
	8.1	Warning and fault messages...........................................................................................................	61

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Contents			Reference Manual
October 2019			00809-0100-3581
	8.2	pH/ORP diagnostics and troubleshooting.......................................................................................	62
	8.3	Contacting and toroidal conductivity diagnostics and troubleshooting..........................................	89
	8.4	Chlorine, dissolved oxygen, and ozone diagnostics.......................................................................	100
	8.5	Chlorine, dissolved oxygen, and ozone troubleshooting...............................................................	103
	8.6	Factory assistance and repairs......................................................................................................	129
Chapter 9	Digital communications.............................................................................................		131
	9.1	HART® communications...............................................................................................................	131
	9.2	FOUNDATION™ Fieldbus communication..........................................................................................	132
	9.3	Asset Management Solutions.......................................................................................................	134
Chapter 10	Return of material......................................................................................................		137
	10.1 General information...................................................................................................................		137
	10.2 Warranty repair..........................................................................................................................		137
	10.3 Non-warranty repair...................................................................................................................		137
Appendix A	Engineering Drawings................................................................................................		139

vi	Rosemount 5081

Reference Manual	Start-up
00809-0100-3581	October 2019

1 Start-up

Procedure

1.Using the infrared remote control (IRC), press PROG, NEXT, NEXT, and ENTER in this order.

2.Select the measurement type and unit of measurement.

3.Use the arrow keys to toggle between Celsius and Fahrenheit.

4.Press ENTER and then RESET.

5.Press PROG, NEXT, and ENTER in this order.

6.Use the arrow keys to toggle T AUTO between ON or OFF.

This determines whether the transmitter uses the process temperature (ON) or a manual temperature (OFF).

7.Press ENTER.

8.If you select OFF, enter the manual temperature desired using the arrow keys.

9.Press ENTER.

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Start-up	Reference Manual
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8	Rosemount 5081

Reference Manual	Description and specifications
00809-0100-3581	October 2019

2 Description and specifications

2.1Features and applications

The Rosemount™ 5081 includes the following features:

General

The Rosemount 5081 explosion-proof transmitter is a loop powered device with a robust design that serves several industrial, commercial, and municipal applications. It offers a local operator interface (LOI) that can display values from a single measurement input. This transmitter is compatible with a multitude of analytical sensors.

Analytical measurements

•pH/ORP

•Contacting conductivity

•Toroidal conductivity

•Dissolved oxygen

•Ozone

•Chlorine

Maintenance features

•Automatic two-point buffer calibration routine

•Automatic recognition of resistance temperature device (RTD)

•Sensor diagnostics

Diagnostics

Continuous monitoring of sensor performance along with warnings and fault messages to alert the user of failures.

Enclosure

Explosion-proof and corrosion resistant

2.2General specifications

Table 2-1: General Specifications

Housing	Cast aluminum with epoxy coating. NEMA® 4X(IP65) and NEMA7B. Neoprene
	O-ring seals.
Dimensions	6.3 x 6.9 x 6.4 in. (160.5 x 175.3 x 161.3 mm) See the engineering drawings in
	Engineering Drawings.
Conduit openings	¾-in. female national pipe thread (FNPT)
Ambient temperature	-4 to 149 °F (-20 to 65 °C)

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Description and specifications		Reference Manual
October 2019		00809-0100-3581
Table 2-1: General Specifications (continued)
Storage temperature	-22 to 176 °F (-30 to 80 °C)
Relative humidity	0 to 95% (non-condensing)
Weight / shipping weight	10 lb./11 lb. (4.5 kg/5.0 kg)
Display	First line: 7 segment LCD, 0.8 in. (20 mm) high. This line shows process
	variables (pH/ORP, contacting conductivity, toroidal conductivity, etc.)
	Second line: 7 segment LCD, 0.3 in. (7 mm) high. This line shows process
	temperature, output current, warnings, faults, and messages during
	calibration/programming.
	Display board can be rotated 90 degrees clockwise or counterclockwise if
	desired.
Temperature resolution	0.1 °C
Hazardous location approval	For details, see Rosemount 5081 - (A/P/C/T) product certifications.
RFI/EMI	Meets all industrial requirements of EN61326.
Diagnostics (may slightly vary based	•	Calibration error
on measurement type)	•	Low temperature error
	•	High temperature error
	•	Sensor failure
	•	Line failure
	•	CPU failure
	•	Calibration error
	•	Zero error
	•	Temperature slope error
	•	Sensor failure
	•	ROM failure
	•	Input warning
	Once one of the above warnings/faults are diagnosed, the LOI will display a
	message describing the failure detected.
Table 2-2: HART® Digital Communications
Power and load requirements	Supply voltage at the transmitter terminals should be at least 12 Vdc. Power
	supply voltage should cover the voltage drop on the cable plus the external
	load resistor required for HART communications (250 Ohms minimum).
	Minimum power voltage is 12 Vdc. Maximum power voltage is 42.4 Vdc
	(30 Vdc for intrinsically safe operation). Figure 4-1 shows the supply voltage
	required to maintain 12 Vdc (upper line) and 30 Vdc (lower line) at the
	transmitter terminals when the current is 22 mA.
Analog output	Two-wire, 4-20 mA output with superimposed HART digital signal, scalable
	over the operating range of the sensor.
Output accuracy	±0.05 mA

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Table 2-2: HART® Digital Communications (continued)
Variables assignable to	•	pH
	•	Temperature
	•	mV
	•	Glass impedance
	•	Reference impedance
	•	RTD resistance
	• Oxidation reduction potential (ORP)
	•	Conductivity
	•	Resistivity
	•	Concentration
	•	Raw conductivity
	•	Chlorine
	•	Dissolved oxygen
	•	Dissolved ozone

Table 2-3: FOUNDATION™ Fieldbus Digital Communications

Power and load requirements	A power supply voltage of 9-32 Vdc at 22 mA is required.
AI blocks assignable to	•	pH
	•	Temperature
	•	mV
	•	Glass impedance
	•	Reference impedance
	•	RTD resistance
	•	ORP
	•	Conductivity
	•	Resistivity
	•	Concentration
	•	Raw conductivity
	•	Chlorine
	•	Dissolved oxygen
	•	Dissolved ozone

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2.3Rosemount 5081 - (A/P/C/T) product

certifications

Rev 1.0

2.3.1European Directive Information

A copy of the EU Declaration of Conformity can be found at the end of the Quick Start Guide. The most recent revision of the EU Declaration of Conformity can be found at Emerson.com/Rosemount.

2.3.2Ordinary Location Certification

As standard, the Power Module has been examined and tested to determine that the design meets the basic electrical, mechanical, and fire protection requirements by a nationally recognized test laboratory (NRTL) as accredited by the Federal Occupational Safety and Health Administration (OSHA).

2.3.3Installing equipment in North America

The US National Electrical Code® (NEC) and the Canadian Electrical Code (CEC) permit the use of Division marked equipment in Zones and Zone marked equipment in Divisions. The marking must be suitable for the area classification, gas, and temperature class. This information is clearly defined in the respective codes.

2.3.4USA

FM hazardous locations

Certificate	FM17US0021X
Standards	FM Class 3600:2011, FM Class 3610:2015, FM Class 3611:2016 FM Class
	3615:2006, FM Class 3810:2005, ANSI/NEMA 250:1991
Markings	Intrinsically safe for use in Class I, II, and III, Division 1, Groups A, B,
	C, D, E, F, and G; T4 Ta = -20 °C to 70 °C; per control drawing numbers
	1400676; 1400677
	Nonincendive for Class I, Division 2, Groups A, B, C, and D; T4 Ta = -20 °C
	to 70 °C; per control drawing numbers 1400676; 1400677
	Dust-ignitionproof for use in Class II and Class III, Division 1, Groups E, F,
	and G; T6 Ta = -20 °C to 70 °C;per control drawing number 1400678
	Explosionproof for use in Class I, Div 1, Groups B, C, and D; T6 Ta = -20 °C
	to 70 °C; per control drawing number 1400678
	Type 4X

Special Conditions for Safe Use (X):

1.The Rosemount 5081-T conductivity transmitters shall only be used with the Rosemount 222, 225, 226, 228 (1 in. and 2 in. only) and 245 toroidal sensors.

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2.3.5Canada

CSA hazardous locations Certificate 1132747

Standards C22.2 No. 0-M1987, C22.2 No. 25-1966, C22.2 No. 30-M1986 C22.2 No. 94-M91, C22.2 No 142-M1987, C22.2 No. 157-92, C22.2 No. 213M1987

Markings

Intrinsically safe for Class I Groups A, B, C, and D; Class II Groups E, F, and G; Class III; T4 Tamb = 70 °C, per installation drawing 1400674 and 1400675

Non-incendive for Class I, Div. 2 for Groups A, B, C, and D; Class II, Div. 2, Groups F and G; Class III; T4 Tamb = 70 °C, per installation drawing 1400674 and 1400675 (Rosemount 5081-A/P/C/T) and per 1700462 (Rosemount 5081-T)

Explosion-proof for Class I, Groups B, C, and D; Class II, Groups E, F, and G, Class III, T6 Tamb = 70 °C

Type 4X

2.3.6Europe

Rosemount 5081-A and 5081-P liquid transmitters

ATEX

Certificate BAS02ATEX1284X

Standards EN 60079-0:2012+A11:2013

EN 60079-11:2012

Markings	II 1 G
	Ex ia IIC T4 Ga
	(-20 °C ≤ Ta ≤ +65 °C)

Special Conditions for Safe Use (X):

1.The Rosemount 5081 enclosure may be made of aluminum alloy and given a protective polyurethane paint finish; however, care should be taken to protect it from impact or abrasion of located in a zone 0.

Rosemount 5081-C liquid transmitter

ATEX
Certificate	Baseefa03ATEX0099X
Standards	EN 60079-0:2012+A11:2013
	EN 60079-11:2012

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Description and specifications	Reference Manual
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Markings	II 1 G

Ex ia IIC T4 Ga

(-20 °C ≤ Ta ≤ +65 °C)

Special Conditions for Safe Use (X):

1.The equipment enclosure may contain light metals. The equipment must be installed in such a manner as to minimize the risk of impact or friction with other metal surfaces.

Rosemount 5081-T liquid transmitter

ATEX

Certificate Baseefa03ATEX0399X

Standards EN 60079-0:2012+A11:2013

EN 60079-11:2012

Markings	II 1 G
	Ex ia IIC T4 Ga
	(-20 °C ≤ Ta ≤ +65°C)

Special Conditions for Safe Use (X):

1.The equipment may contain light metals. The equipment must be installed in such a manner as to minimize the risk or impact or friction with other metal surfaces.

2.3.7International

IECEx
Certificate	IECEx BAS 09.0159X
Standards	IEC 60079-0:2011
	IEC 60079-11:2011
Markings	Ex ia IIC T4 Ga
	(-20 °C ≤ Ta ≤ +65°C)

Special Conditions for Safe Use (X):

1.The Rosemount 5081 enclosure may be made of aluminum alloy and given a protective polyurethane paint finish; however, care should be taken to protect it from impact or abrasion if located in a zone 0 environment.

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2.4Functional specifications

The sections below display the specifications for measuring different substances with the Rosemount 5081.

2.4.1pH/ORP specifications

pH range	0 to 14
ORP range	-1400 to +1400 mV
Calibration/standardization	The automatic buffer recognition uses stored buffer values and
	their temperature curves for the most common buffer standards
	available worldwide. The transmitter also performs a stabilization
	check on the sensor in each buffer. To make a manual two-point
	calibration, immerse the sensor in two different buffer solutions
	and enter the pH values. The microprocessor automatically
	calculates the slope which is used for self-diagnostics. The
	transmitter displays an error message if the pH sensor is faulty.
	The operator can read the slope on the display and/or manually
	adjust it if desired. To complete an on-line, one-point
	standardization process, enter the pH or ORP value of a grab
	sample as measured by a lab reference.
Preamplifier location	Use a preamplifier to convert the high impedance pH electrode
	signal to a low impedance signal for transmitter use. Use the
	transmitter's integral preamplifier when the sensor to transmitter
	distance is less than 15 ft. (4.5 m). Use a sensor with a built-in
	preamplifier or a junction box if distance is longer than 15 ft. (4.5
	m).
Automatic temperature	External 3 or 4 wire Pt 100 resistance temperature device (RTD)
compensation	or Pt 1000 RTD, located in the sensor, compensates the pH
	reading for temperature fluctuations. Compensation covers the
	range 5 to 270 °F (-15 to 130 °C). The operator may also select
	manual temperature compensation.
Accuracy	±01 mv at 77 °F (25 °C) ± 0.01 pH
Repeatability	±01 mv at 77 °F (25 °C) ±0.01 pH
Stability	0.25% / year at 77 °F (25 °C)

2.4.2Contacting conductivity specifications

Measured range	0-20,000 µS/cm
Calibration	To calibrate, immerse the sensor in a known solution and enter its value or
	enter the cell constant for ultra-pure applications.
Automatic temperature compensation	3-wire Pt 100 or Pt 1000 resistance temperature device (RTD)
	Conductivity: 32 to 392 °F (0 to 200 °C)
	Resistivity: 32 to 212 °F (0 to 100 °C)
	Low conductivity: 32 to 212 °F (0 to 100 °C)
Accuracy	± 0.5% of reading and ±0.001 µS/cm

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Description and specifications	Reference Manual
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Repeatability	± 0.25% of reading
Stability	0.25% of output range/month, non-cumulative
Ambient temperature coefficient	± 0.05% of reading/°C
Temperature slope adjustment	0 to 5%/°C
Other temperature compensation	Ultra-pure water compensation
algorithms	Cation conductivity
	Raw (uncompensated) conductivity
Compatible RTD	100 Ohm or 1000 Ohm with automatic recognition

2.4.3Toroidal conductivity specifications

Measured range	50 to 2,000,000 µS/cm
Calibration	To calibrate, immerse the sensor in a known solution and enter its value.
Automatic temperature compensation	3-wire Pt 100 resistance temperature device (RTD)
	Conductivity: 32 to 392 °F (0 to 200 °C)
	% concentration: 32 to 212 °F (0 to 100 °C)
Accuracy	±1.0% of reading
Repeatability	±0.25% of reading
Stability	0.25% of output range/month, non-cumulative
Ambient temperature coefficient	±0.2% of FS/°C
Temperature slope adjustment	0 to 5% / °C
% concentration ranges	Sodium hydroxide: 0 to 15%
	Hydrochloric acid: 0 to 16%
	Sulfuric acid: 0 to 25% and 96 to 99.7%

2.4.4	Dissolved oxygen specifications
Measurement range		0 - 99 ppm (mg/L), 0 - 200 saturation
Resolution		0.01 ppm, 0.1 ppb for Rosemount 499ATrDO sensor
Temperature correction for		Automatic between 32 and 122 °F (0 and 50 °C). Can be disabled.
membrane permeability
Calibration		Air calibration (user must enter barometric pressure) or calibration against a
		standard instrument

2.4.5	Free chlorine specifications
Measurement range		0-20 ppm (mg/L) as Cl2
Resolution		0.001 ppm (auto-ranges at 0.999 to 1.00 and 9.99 to 10.0)
Temperature correction for		Automatic between 32 and 122 °F (0 and 50 °C). Can be disabled.
membrane permeability

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pH correction	Automatic between pH 6.0 and 9.5. Manual pH correction is also available.
Calibration	Calibrate against grab sample with portable test kit.

2.4.6	Total chlorine specifications
Measurement range		0-20 ppm (mg/L) as Cl2
Resolution		0.001 ppm (auto-ranges at 0.999 to 1.00 and 9.99 to 10.0)
Temperature correction for		Automatic between 41 and 95 °F (5 and 35 °C). Can be disabled.
membrane permeability
Calibration		Calibrate against grab sample with portable test kit.

2.4.7	Ozone specifications
Measurement range		0-10 ppm (mg/L)
Resolution		0.001 ppm (auto-ranges at 0.999 to 1.00 and 9.99 to 10.0)
Temperature correction for		Automatic between 41 and 95 °F (5 and 35 °C). Can be disabled.
membrane permeability
Calibration		Against grab sample analyzed using portable test kit.

2.4.8	Percent oxygen in gas
Measurement range		0 - 25% oxygen
Resolution		0.1% - TBD
Calibration		Air calibration (automatic measurement of barometric pressure with internal
		pressure sensor)
Sample pressure		0 to 50 psig
Sample temperature		32 to 110 °F (0 to 43 °C)

2.5Ordering information

The Rosemount 5081 two-wire transmitter is intended for the determination of pH/ORP, conductivity (both contacting and toroidal), and for measurements using membranecovered amperometric sensors (oxygen, ozone, and chlorine). For free chlorine measurements, which often require continuous pH correction, a second input for a pH sensor is available. Use a hand-held infrared remote controller to locally configure and calibrate the transmitter.

Rosemount 5081	Smart two-wire microprocessor transmitter
Option	Description
P	pH/ORP
C	Contacting conductivity

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Description and specifications	Reference Manual
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T	Toroidal conductivity
A	Amperometric (oxygen, ozone, and chlorine)
Option	Description
HT	Analog 4-20 mA output with superimposed HART® digital signal
FF	FOUNDATION™ Fieldbus digital output
FI	FOUNDATION Fieldbus digital input with FISCO
Option	Description
20	Infrared remote controller included
21	Infrared remote controller not included
Option	Description
60	No approval
67	FM approved intrinsically safe, non-incendive (when used with
	appropriate sensor and safety barrier), and explosion-proof
69	CSA approved intrinsically safe, non-incendive (when used with
	appropriate sensor and safety barrier), and explosion-proof
73	ATEX/IECEx approved intriniscally safe (when used with
	appropriate sensor and safety barrier)
Example	5081-P-HT-20-67

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3 Install

3.1Unpack and inspect

To unpack the instrument:

Procedure

1.Inspect the shipping container(s). If there is damage, contact the shipper immediately for instructions.

2.If there is no apparent damage, unpack the container(s).

3.Ensure that all items shown on the packing list are present.

If items are missing, contact your local Customer Care representative

4.Save the shipping container and packaging.

They can be used to return the instrument to the factory in case of damage.

3.2Installation guidelines

1.The transmitter tolerates harsh environments. For best results, install the transmitter in an area where temperature extremes, vibrations, and electromagnetic and radio frequency interference are minimized or absent.

2.To prevent unintentional exposure of the transmitter circuitry to the plant environment, keep the security lock in place over the circuit end cap. To remove the circuit end cap, loosen the lock nut until the tab disengages from the cap end and then unscrew the cover.

3.The transmitter has two ¾-in. conduit openings, one on each side of the housing. Run sensor cable through the left side opening (as viewed from the wiring terminal end of the transmitter) and run power wiring through the right side opening.

4.Use water tight cable glands to keep moisture out of the transmitter.

5.If using conduit, plug and seal the connections at the transmitter housing to prevent moisture from getting inside the transmitter.

CAUTION

Equipment damage

Moisture accumulating in the transmitter housing can affect the performance of the transmitter and may void the warranty.

6.If the transmitter is installed some distance from the sensor, a remote junction box with preamplifier in the junction box or in the sensor may be necessary. Consult the sensor reference manual for maximum cable lengths.

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3.3Orient the display board

The display board can be rotated 90 degrees, clockwise or counterclockwise, from the original position. To reposition the display:

Procedure

1.Loosen the cover lock nut until the tab disengages from the circuit end cap. Unscrew the cap.

2.Remove the three bolts holding the circuit board stack.

3.Lift and rotate the display board 90 degrees, clockwise or counterclockwise, into the desired position.

4.Position the display board on the stand offs. Replace and tighten the bolts.

5.Replace the circuit end cap.

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3.4Mount on a flat surface

Figure 3-1: Mounting Transmitter on a Flat Surface

A.Cover lock

B.Threaded cap (two places)

C.Terminal block (TB). Terminal end cap omitted for clarity this view.

D.¼-in. - 20 threads (four places)

E.Surface plate (by others)

F.O-ring (two places)

G.Circuit end

H.Terminal end

I.Flat surface mounting pad hole pattern

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3.5Mount on a pipe

Use pipe mounting kit (23820-00 or 23820-01).

Figure 3-2: Mounting Transmitter on a Pipe

A.Over look

B.Terminal block

C.Kit, 2-in. pipe/wall mounting bracket Order PN2002577 as a separate item.

D.½ - 20 threads

E.¼ - 20 screw

Screws furnished with mounting kit only. Not furnished with transmitter.

F.1½-in. to 2-in. pipe (customer furnished)

G.U-bolt

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H.5/16 washer

I.6/18 - 18 nut

J.¾ - 14 FNPT (two places)

K.2-in. pipe supplied by customer

L.¾ - 14 NPT (two places)

M.Threaded cap, two places

N.Circuit end

O.Terminal end

P.Terminal end cap omitted for clarity this view

Q.Four mounting holes

R.Bottom view

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4 Wire

4.1Wiring overview

To find wiring diagrams for specific sensors, check the wiring sections of the reference manuals for those particular sensors.

4.2Power supply/current loop

4.2.1Power supply overview

The tables below display the minimum and maximum voltages needed to operate the transmitter.

Minimum supply voltage at the transmitter	12.0 Vdc
terminals
Minimum power supply for load resister	250 Ohms
Maximum power supply voltage	42.0 Vdc
Maximum power supply voltage for intrinsically	30.0 Vdc
safe installations

Figure 4-1: Power Supply Voltage for HART® or without HART Communication

Configurations

A.With HART communication

B.Without HART communication

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	Table 4-1: Values from Graph
	Upper line	Power supply voltage needed to provide 12 Vdc
		at the transmitter terminals for a 22 mA current
	Lower line	Power supply voltage needed to provide 30 Vdc
		for a 22 mA current
	Maximum current	About 24 mA
	Minimum load for digital communications	250 Ohms
	Minimum power supply voltage to supply the	17.5 Vdc
	12.0 Vdc lift off voltage at the transmitter

4.2.2Wire to HART® or FOUNDATION™ Fieldbus communication protocol

Procedure

1.Run the power/signal wiring through the opening nearest terminals 15 and 16.

2.Use shielded cable and ground the shield to the power supply.

3.To ground the transmitter, attach the shield to the grounding screw on the inside of the transmitter case.

You can also use a third wire to connect the transmitter to earth ground.

Note

For optimum EMI/RFI immunity, shield the power supply and enclose it in an earth ground metal conduit. Do not run power supply/signal wiring in the same conduit or cable tray with AC power lines or with relay actuated signal cables. Keep power supply/signal wiring at least 6 ft. (2 m) away from heavy electrical equipment. An additional 0-1 mA current loop is available between TB-14 and TB-15. A 1 mA current in this loop signifies a sensor fault. See Figure 4-2 for wiring instructions. See Diagnostics and troubleshooting for more information about sensor faults.

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Figure 4-2: General Wiring Architecture

A.Filter

B.Terminators

C.Trunk

D.Spur

The power supply, filter, first terminator, and configuration device are typically located in the control room.

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5 Display and operate

5.1User interface and main display

The following are examples of the main (process) display screen (Figure 5-1) and the program display screen (Figure 5-2).

Figure 5-1: Main Display Screen

A.Conductivity value

B.Temperature in °C or °F

Figure 5-2: Program Display Screen

A.Indicates HART® or FOUNDATION™ Fieldbus digital communiciations

B.Conductivity value

C.Units of display

D.Active menu: CALIBRATE, PROGRAM, or DIAGNOSE

E.Sub-menus, prompts, and diagnostic messages appear here.

F.Available commands for sub-menus, prompts, or diagnostic messages

G.Appears when transmitter is in hold

H.Appears when a disabling condition has occurred

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5.2Infrared remote control (IRC)

Use the IRC to read diagnostics messages, calibrate connected sensors, and program the transmitter. Hold the IRC within 6 ft. (1.8 m) of the transmitter and less than 15 degrees from the horizontal of the display window.

Figure 5-3: Infrared Remote Control (IRC) Functions

1. RESET			6. HOLD
• End current operation and			• Access to turn hold readings
return to the main display.				on or off.
• Changes are not saved.
• Does not return the
transmitter to factory default
settings.
2. Editing (arrow) keys			7. ENTER
• Change values of a flashing			• Advance to the next prompt.
display.			•	Store selected item.
• Left and right arrows move
			• Store value in memory.
the cursor by one digit.
• Up and down arrows increase
or decrease the values and
navigate through the display
options.
3. CAL			8. NEXT
• Access to Calibration menu.			• Advance to the next sub-
				menu.
4. PROG			9. EXIT
• Access to Program menu.			•	End current operation.
			• Return to the first prompt in
5. DIAG
				the present sub-menu.
• Access to diagnostics.
			• Changes are not saved.

Guidelines for using IRC

•Do not use harsh chemicals or abrasive brushes when cleaning the remote control.

•If the green LED does not light when you press a key, the issue is probably a weak battery. To restore operation, remove four screws to access and replace the two batteries. Observe the two warning messages posted at the rear of the remote control.

•Requires two 1.5 V AAA batteries. If used in hazardous areas, replacement batteries must be Energizer E92/EN92 or Duracell MN2400/PC2400.

•All functions for remote control PN 24479-00 are the same as those for the previous remote control, PN 23572-00.

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