Rosemount 1181-T Two-Wire Toroidal Transmitter Manuals & Guides

Model 1181T

Two-Wire Toroidal Conductivity Transmitter

Instruction Manual

PN 51-1181T/rev.C
April 2003

DANGER

HAZARDOUS AREA INSTALLATION

INTRINSICALLY SAFE INSTALLATION

Installations in hazardous area locations must be
carefully evaluated by qualified on site safety per­sonnel. Transmitter and Sensor alone are not
Intrinsically safe. To secure and maintain an intrin­sically safe installation, a certified safety barrier
must be used and the installation must comply with
the governing approval agency (FM, CSA or
BASEEFA/CENELEC) installation drawing require­ments (see Section 2.0 - Installation).

EXPLOSION-PROOF INSTALLATION

Caution: Sensors are not explosion-proof. If the
sensor must be installed in a hazardous location an
intrinsically safe system must be implemented.

To maintain the explosion-proof rating of the trans­mitter, the following conditions must be met:

• Discontinue power supply before removing
enclosure covers.

• Transmitter covers must be properly installed
during power on operation.

• Explosion proof "Y" fittings must be properly
installed with sealing compound prior to apply­ing power to the transmitter.

• Serial tag cover over the external Zero and
Span adjustments must be in place.

• See Installation Section for details.

Proper installation, operation and servicing of this
instrument in a Hazardous Area Installation is
entirely the responsibility of the user.

ESSENTIAL INSTRUCTIONS

READ THIS PAGE BEFORE PROCEEDING!

Rosemount Analytical 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 Rosemount
Analytical 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 Instruction Manual is not the correct manual, telephone 1-800­654-7768 and the requested manual will be provided. Save this
Instruction Manual for future reference.

• If you do not understand any of the instructions, contact your Rosemount
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 your equipment as specified in the Installation Instructions of the
appropriate Instruction 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 Rosemount. Unauthorized parts and pro­cedures can affect the product’s performance and place the safe opera­tion of your process at risk. 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 per­sons, to prevent electrical shock and personal injury.

Emerson Process Management

Liquid Division

2400 Barranca Parkway
Irvine, CA 92606 USA
Tel: [phone]
Fax: [phone]

http://www.raihome.com

© Rosemount Analytical Inc. 2003

About This Document

This manual contains instructions for installation and operation of Model 1181T Two-wire Toroidal
Conductivity Transmitter. The following list provides notes concerning all revisions of this document.

Rev

. Level Date Notes

0 5/00 The initial release of the product manual. The manual has been reformatted to

reflect the Emerson documentation style and updated to reflect any changes in
the product offering.

A 7/01 Added CE addendum info to page 6.

B 7/02 Updated drawing on page 7.

C 4/03 Updated CE cert reference on page 1.

MODEL 1181T

TWO-WIRE TRANSMITTER

TABLE OF CONTENTS

Section Title Page

1.0 GENERAL DESCRIPTION AND SPECIFICATIONS ........................... 1

1.1 Features and Applications.................................................................... 1

1.2 Physical Specifications – General........................................................ 1

1.3 Performance Specifications – General................................................. 2

1.4 Performance Specifications at 25°C .................................................... 3

1.5 Ordering Information............................................................................. 3

2.0 INSTALLATION..................................................................................... 4

2.1 Unpacking and Inspection .................................................................... 4

2.2 Mechanical Installation ......................................................................... 4

2.3 Hazardous Locations-Explosion-Proof Installation............................... 4

2.4 Wiring – General .................................................................................. 6

2.5 Hazardous Locations-Intrinsically Safe Installation.............................. 6

3.0 DESCRIPTION OF CONTROLS.......................................................... 15

3.1 Description of Controls ......................................................................... 15

4.0 CONFIGURATION................................................................................ 19

4.1 General................................................................................................. 19

4.2 Range Selection ................................................................................... 19

4.3 Digital Display....................................................................................... 21

4.4 Temperature Slope Adjustment ............................................................ 22

5.0 START UP AND CALIBRATION........................................................... 23

5.1 Calibration Using a Conductivity Standard or Process Sample........... 23

5.2 In-Situ Calibration by Grab Sample Analysis ....................................... 24

5.3 Full Scale Calibration Using a Decade Box or Resistors..................... 25

6.0 THEORY OF OPERATION................................................................... 26

6.1 Theory of Operation ............................................................................. 26

6.2 Circuit Description ................................................................................ 28

7.0 DISASSEMBLY/REASSEMBLY PROCEDURE ................................... 30

7.1 Disassembly Procedure........................................................................ 30

7.2 Reassembly Procedure ........................................................................ 30

8.0 TROUBLESHOOTING ......................................................................... 31

8.1 General................................................................................................. 31

8.2 Troubleshooting.................................................................................... 31

9.0 SPARE PARTS ..................................................................................... 32

9.1 Spare Parts........................................................................................... 32

10.0 RETURN OF MATERIAL...................................................................... 34

i

MODEL 1181T TABLE OF CONTENTS

ii

TABLE OF CONTENTS (CONT'D)

LIST OF FIGURES

Number Title Page

2-1 Mounting and Dimensional Drawing......................................................... 5

2-2 Transmitter Wiring..................................................................................... 7

2-3 Schematic System, F.M. I.S. Approved 1181T (1 of 3) ............................ 8

2-3 Schematic System, F.M. I.S. Approved 1181T (2 of 3) ............................ 9

2-3 Schematic System, F.M. I.S. Approved 1181T (3 of 3) ............................ 10

2-4 Schematic System, 1181T (CSA) ............................................................. 11

2-5 Intrinsically Safe Operation 1181T (CENELEC) ....................................... 12

2-6 FM Approved Explosion Proof Installation................................................ 13

3-1 External Span and Zero............................................................................ 16

3-2 Model 1181T PCB Stack........................................................................... 16

3-3 Temperature Circuit Board ........................................................................ 17

3-4 Driver Circuit Board .................................................................................. 17

3-5 Transmitter Circuit Board.......................................................................... 17

3-6 Signal Input Circuit Board......................................................................... 18

4-1 Model 1181T Matrix Cover........................................................................ 20

4-2 Digital Display ........................................................................................... 21

5-1 1181T Calibration Setup ........................................................................... 25

6-1 Toroidal Conductivity Principle .................................................................. 26

6-2 Model 1181T Operation Block Diagram.................................................... 27

6-3 Model 1181T Schematic ........................................................................... 29

9-1 Model 1181T Two Wire Transmitter Parts ................................................ 33

LIST OF TABLES

Number Title Page

4-1 Full Scale Readings of the 1181T With Various

Probe Constants in Microsiemens/cm ...................................................... 19

4-2 Operational Limits vs. Slope..................................................................... 22

8-1 Troubleshooting Guide.............................................................................. 31

9-1 Model 1181T Two-Wire Transmitter Spare Parts ..................................... 32

MODEL 1181T TABLE OF CONTENTS

1

MODEL 1181T SECTION 1.0

GENERAL DESCRIPTION AND SPECIFICATIONS

1.1 FEATURES AND APPLICATIONS

The Rosemount Analytical Two-Wire field mounted
transmitters, with the appropriate sensors, are designed
to continuously measure the pH, ORP, Conductivity,
Dissolved Oxygen, or Free Residual Chlorine in industri­al processes.

The Model 1181 Transmitters include all the circuitry
necessary for the measurement and transmission of an
isolated 4-20 mA linear signal. Measurement range
selection is made through internal range switches that
are easily accessed by removing a housing cover. No
further disassembly is required. A matrix is provided
which conveniently indicates the proper switch position.
Range selection can be made without the use of the
instruction manual. Fine calibration of the 4-20 mA sig­nal is accomplished with the 20-turn external Zero and
Span potentiometers.

The electronic printed circuits are protected from the
environment by the NEMA 4X weatherproof, corrosion
resistant enclosure. The printed circuit cards plug into a
moisture barrier which is isolated from the field wiring
and calibration terminals. Routine field calibration does
not require exposing the electronics to harsh industrial
environments. All PCBs are conformal coated for maxi­mum protection. The PCBs are removed as a unit and
may be individually replaced. The transmitter housing
covers are sealed with large cross sectional O-rings and
need not be replaced each time the cover is removed.

The Model 1181 is available blind or with an analog or
digital display. The digital display may be calibrated in
engineering units and the analog display features multi­ple scales in engineering units.

The transmitters are certified explosion-proof, NEMA 7B,
and intrinsically safe when installed with an approved
barrier and sensor. Hazardous area certificates are pro­vided by BASEEFA to CENELEC regulations, FM, CSA,
SAA, SEV, and TUV. CSA has determined that the mois­ture barrier qualifies as Factory Sealed which means
Explosion Proof Y fittings and sealing compound are not
required for installation when this approval is selected.

Accessory items are available for the two-wire transmit­ters. The Model 515 Isolated Power Supply provides
power for up to 20 transmitters. Two transmitters may be

wired directly to the power supply. For more than two
transmitters, junction boxes are available, each accom­modating wiring for a maximum of ten transmitters.
Remote alarms are available with independently
adjustable set points and hysteresis. Contacts of the
Model 230A may be specified for high/low, high/high, or
low/low operation. The impedance of the Model 230A
Alarm Module is less than 100 ohms. For further infor­mation on the Models 515 and 230A, please refer to
their respective product data sheet.

1.2 PHYSICAL SPECIFICATIONS – GENERAL

Enclosure: NEMA 4X, weatherproof and corrosion-

resistant

NEMA 7B, explosion proof

Hazardous Area Classification:

Explosion Proof:

FM: Class I, Groups B, C, & D, Div. 1

Class II, Groups E, F, & G, Div. 1
Class III
60°C Maximum

CSA: Class I, Groups C & D

Class II, Groups E, F, & G
Class III
Class I, Groups A, B, C, & D, Div. 2
Encl. Type 4, Factory Sealed

Intrinsic Safety:

FM: Class I, II, & III, Div. 1

Temperature Code T4

CSA: Class I, Groups A, B, C, & D, Encl 4

Temperature Code T4

CENELEC: Ex ia IIB T4

Display:

Analog: plug in, 90 degree, 2.5 inch diameter

1181T: single scale, 0-100%

Digital: 3.5 digit, LCD, adjustable range in

engineering units

EMI/RFI: EN-61326

SECTION 1.0

GENERAL DESCRIPTION AND SPECIFICATIONS

2

MODEL 1181T SECTION 1.0

GENERAL DESCRIPTION AND SPECIFICATIONS

Recommended
Cable: Transmitter to Power Supply Two Wire, 18 AWG,

shielded, Belden 8760 or equal (Rosemount
Analytical P/N 9200001)

Weight/Shipping Weight:

Blind: 1.8 kg/2.25 kg (4.0 lbs/5.0 lbs)
Analog/Digital: 2.48 kg/2.93 kg (5.5 lbs/6.5 lbs)

1.3 PERFORMANCE SPECIFICATIONS –
GENERAL

Power Supply Requirements: (See Load/Supply

Chart)

Lift Off Voltage:

Blind & Analog: 10 VDC
Digital: 12.5 VDC

Maximum Operating Power: 40 milliwatts

Output: Blind & Analog: Isolated 4-20 mA into

700 ohms at 24 VDC

Digital: Isolated 4-20 mA into 575 ohms at

24 VDC

Input/Output Isolation: 600 Volts

Ambient Temperature: –25° to 70°C

Relative Humidity: 0-99%

Digital Display Accuracy: 0.1% reading ±1.0 count

Analog Display Accuracy: ±2.0%

External Zero: ±25%

External Span: ±50%

Shock: 10G maximum for 10 milliseconds

Vibration: 0.025 inches double amplitude

5 to 50 Hz for 2 hours

The Model 1181T Toroidal Transmitter measures con-
ductivity over the range of 0-50 µS/cm to 0-1000 mS/cm.
The Model 1181T uses an inductive principal of meas­urement and employs the use of toroidal or electrode­less conductivity sensors. Toroidal conductivity sensors
have no exposed electrodes to the measured solution,
which practically eliminates routine sensor maintenance
in applications where electrode fouling may occur. A
unique feature of the Model 1181T is the 0-4% tempera­ture slope adjustment which provides greater accuracy
in chemical concentration control. The 0-4% tempera­ture slope adjustment eliminates the need for special
temperature compensation circuits required for the cali­bration to a specific acid, base, or salt over a specific
operating temperature range.

BLIND & ANALOG DISPLAY

LOAD/POWER SUPPLY REQUIREMENTS

+45 VDC @ 600 OHMS MIN. 1750 OHMS MAX.

10 VDC 24 VDC 33 VDC @ ZERO LOAD 45 VDC

LIFT OFF NOMINAL MAXIMUM

POWER SUPPLY VOLTAGE

1750 OHMS
@ 45 VDC

600 OHMS
@ 45 VDC

LOAD
RESISTANCE
REQUIRED

1.8 –

1.7 –

1.6 –

1.5 –

1.4 –

1.3 –

1.2 –

1.1 –

1.0 –

0.9 –

0.8 –

0.7 –

0.6 –

0.5 –

0.4 –

0.3 –

0.2 –

0.1 –

0.0 –

OPERATING

REGION

DIGITAL DISPLAY

LOAD/POWER SUPPLY REQUIREMENTS

+45 VDC @ 600 OHMS MIN. 1750 OHMS MAX.

12.5 VDC 24 VDC 35.5 VDC @ ZERO LOAD 45 VDC
LIFT OFF NOMINAL MAXIMUM

POWER SUPPLY VOLTAGE

1750 OHMS
@ 45 VDC

600 OHMS
@ 45 VDC

LOAD
RESISTANCE
REQUIRED

1.8 –

1.7 –

1.6 –

1.5 –

1.4 –

1.3 –

1.2 –

1.1 –

1.0 –

0.9 –

0.8 –

0.7 –

0.6 –

0.5 –

0.4 –

0.3 –

0.2 –

0.1 –

0.0 –

OPERATING

REGION

3

RECOMMENDED TOROIDAL SENSORS:

FULL SCALE

Minimum Maximum

Model 222 Sensor 0-500 µS/cm 0-1000 mS/cm
Model 225 Sensor 0-250 µS/cm 0-1000 mS/cm
Model 226 Sensor 0-80 µS/cm 0-160 mS/cm
Model 228 Sensor 0-250 µS/cm 0-1000 mS/cm

MODEL

1181 TWO-WIRE TRANSMITTER

CODE INPUT (Required Selection)

T Toroidal Conductivity

CODE DISPLAY (Required Selection)

01 FM and CSA approved analog display

02 Blind, without indication

03 FM, CSA and CENELEC approved analog display

06 CSA, & CENELEC approved digital display

CODE OPTIONS

07 Two-inch pipe/wall mounting bracket (order as P/N 2002577)

11 Stainless steel nameplate (specify marking) (order as P/N 9240591)

CODE AGENCY APPROVALS

67 FM Explosion proof and Intrinsically Safe

69 CSA Explosion proof and Intrinsically Safe

73 CENELEC Intrinsically Safe

1181 T 01 07-11 67 EXAMPLE

1.5 ORDERING INFORMATION

Model 1181 Two Wire Transmitter is housed in a NEMA 7B explosion-proof, 4X weatherproof, corrosion-resistant

enclosure and includes all the circuitry necessary for measurement and transmission of an isolated 4-20 mA signal. The
transmitter may be selected with or without an analog or digital display.

MODEL 1181T SECTION 1.0

GENERAL DESCRIPTION AND SPECIFICATIONS

1.4 PERFORMANCE SPECIFICATIONS @ 25°C

Measurement Range: 0-80 µS/cm minimum

0-1000 mS/cm maximum

Internal Range Select: Multipliers X500, X1000,

X10,000 with jumper selectable
span X1 & X10 and internal
span adjust

Accuracy: ±0.5% full scale

Stability: ±0.1%/month, non-cumulative

Repeatability: ±0.1% full scale

Temperature Coefficient: 0.05% of F.S./°C

Temperature Slope Adjust: 0-4%/°C

Automatic Temperature Compensation: 0-200°C

4

MODEL 1181T SECTION 2.0

INSTALLATION

SECTION 2.0

INSTALLATION

2.1 UNPACKING AND INSPECTION

Before opening the shipping carton, inspect the outside
of the carton for any damage. If damage is detected,
contact the carrier immediately. If there is no apparent
damage, open the carton and inspect the instrument and
hardware. Make sure all the items in the packing list are
present and in good condition. Notify the factory if any
part is missing. If the instrument appears to be in satis­factory condition, proceed to the transmitter installation.

NOTE

Save the original packing cartons and
materials as most carriers require proof of
damage due to mishandling, etc., also, if it
is necessary to return the instrument to the
factory, you must pack the instrument in
the same manner as it was received. (refer
to Section 8 for return instructions).

2.2 MECHANICAL INSTALLATION

IMPORTANT

Do not attempt to install and operate the
Model 1181T without first reading this
manual.

2.2.1 General. The transmitter may be installed in harsh
environments. However, it should be installed in an area
where sources of extreme temperature fluctuation, vibra­tion and shock are at a minimum or non-existent. Select
an installation site that (1) permits the use of the standard
cable lengths of 20 feet (6.1 m) or 10 feet (3.0 m); (2) is
easily accessed by operating and maintenance person­nel; (3) is at least 12 inches (300 mm) from sources of
high voltage.

2.2.2 Mounting. The Transmitter may be mounted on a
flat surface using the two threaded mounting holes locat­ed on the bottom of the transmitter or through the use of
an optional 2-inch pipe/wall mounting bracket, Code 07
(Figure 2-1).

2.3 HAZARDOUS LOCATIONS–EXPLOSION
PROOF INSTALLATIONS

In order to maintain the explosion proof rating for the
installed transmitter, the following conditions must be
met:

1. The transmitter enclosure covers must be on hand

tight and the threads must not be damaged.

NOTE

These covers seat on o-rings which serve
to provide a dust proof enclosure for Class
II and Class III installations.

2. Explosion proof "Y" fittings must be properly installed

and plugged with a sealing compound to prevent
explosive gases from entering the transmitter. CSA
has determined that the transmitter housing is
"Factory Sealed". Installation of "Y" fittings and the
use of sealing compound is not required for CSA
approved Explosion Proof installations.

NOTE

Do not install sealing compound until all
field wiring is complete.

3. If one of the conduit connections on the housing is

not used, it must be closed with a threaded metal
plug with at least five threads engaged.

4. The serial tag cover on the external ZERO and SPAN

adjustments must be in place.

5. Explosion proof installation must be in accordance

with drawing number 1400155 (See Figure 2-6).

6. Due to the nature of the measurement, sensors can-

not be designed to meet explosion proof certification.
If the sensors must be installed in hazardous area
locations, Rosemount Analytical Inc. recommends
that an intrinsically safe system be installed.

CAUTION

Sealing compound must be installed prior
to applying power to the transmitter.

5

FIGURE 2-1. Mounting and Dimensional Drawing

MODEL 1181T SECTION 2.0

INSTALLATION

6

MODEL 1181T SECTION 2.0

INSTALLATION

2.4 WIRING– GENERAL

The transmitter is equipped with two 1¼2-inch conduit
openings, one on each side of the housing. One is for the
power supply/signal wiring and the other is for the sensor
wiring.

The use of waterproof cable glands or conduit is recom­mended to prevent moisture from entering the housing. If
conduit is used, it should be positioned to prevent con­densation from draining into the housing.

Twisted pairs are recommended for the signal cable. The
twisted pairs should also be shielded and grounded. The
transmitter case shall be grounded.

Signal or sensor wiring should never be run in the same
conduit or open tray with AC power, or relay actuated sig­nal cables. Keep signal or sensor wiring at least 12 inch­es from heavy electrical equipment.

NOTE

For best EMI/REI protection the power
supply/signal cable should be shielded and
enclosed in an earth grounded rigid metal con­duit. Connect the cable’s outer shield to the earth
ground terminal near TB1, Figure 2-2.

The sensor cable should also be shielded. The
cable’s outer shield shall be connected to the
earth ground terminal provided near TB1, Figure
2-2. If the outer shield is braided an appropriate
metal cable gland fitting may be used to connect
the braid to earth ground via the instrument case.

A new addition to the suite of tests done to
ensure CE compliance is IEC 1000-4-5. This is a
surge immunity test that simulates overvoltages
due to switching and lightning transients.

In order to meet the requirements of this test,
additional protection must be added to the
instrument in the form of a Transient Protector
such as the Rosemount Model 470D. This is a
3½-inch tube with ½-inch MNPT threads on both
ends. Inside the tube are gas discharge and
zener diode devices to limit surges to the trans­mitter from the current loop. No additional pro­tection is needed on the sensor connections.

2.4.3 Sensor Wiring. The Sensor wiring terminals are
located on the side of the housing designated TERM
SIDE on the serial label. Remove the housing cover from
the TERM SIDE to gain access to the terminals desig­nated TB2. Remove the optional Analog or Digital dis­play. The plug in analog display is held in by a spring clip
and the digital display is held in by a locking screw.
Connect the sensor wiring to TB2 terminals 1 through 4
as shown on drawing 40118121 (Figure 2-2).

NOTE

Sensors are supplied with a standard cable
length of 20 feet (6.1 m) or 10 feet (3.0 m).
If the standard cable length is not sufficient
for the planned installation, the use of a
junction box with extension cable is strong­ly recommended. Cutting or extending the
cable may reduce performance and will
void warranty.

2.4.2 Power and Signal Wiring. The power and signal

wiring terminals are located directly above the Sensor
wiring terminals and are designated TB1. TB1 also
provides for plugging in the optional Analog display or
wiring of the optional digital display.

2.5 HAZARDOUS LOCATIONS–

INTRINSICALLY SAFE INSTALLATION

To secure and maintain intrinsically safe installation
for the appropriate approval agency, the following con­ditions must be met:

1. Code 73 must be specified when ordering CENELEC

units and installation must be performed in accor­dance with Drawing Number 6-012-BO26 (Figure 2-

5).

2. Code 69 must be specified when ordering CSA

(Canadian Standards Association) units. Installation
must be performed in accordance with Drawing
Number 1400150 (Figure 2-4).

3. Code 67 must be specified when ordering F.M. units.

Installation must be accordance with Drawing
Number 1400128 (Figure 2-3).

CAUTION

Do not exceed 100 feet (30.5m) distance
of total cable length between the
Transmitter and the Sensor.

7

MODEL 1181T SECTION 2.0

INSTALLATION

FIGURE 2-2. Transmitter Wiring

DWG. NO. REV.

40118121 J

8

MODEL 1181T SECTION 2.0

INSTALLATION

FIGURE 2-3. Schematic System, F.M. I.S. Approved 1181T (1 of 3)

DWG. NO. REV.

1400128 L

9

MODEL 1181T SECTION 2.0

INSTALLATION

FIGURE 2-3. Schematic System, F.M. I.S. Approved 1181T (2 of 3)

DWG. NO. REV.

1400128 L

10

MODEL 1181T SECTION 2.0

INSTALLATION

FIGURE 2-3. Schematic System, F.M. I.S. Approved 1181T (3 of 3)

DWG. NO. REV.

1400128 L

11

MODEL 1181T SECTION 2.0

INSTALLATION

FIGURE 2-4. Schematic System, 1181T (CSA)

DWG. NO. REV.

1400150 D

12

MODEL 1181T SECTION 2.0

INSTALLATION

FIGURE 2-5. Intrinsically Safe Operation, 1181T (CENELEC)

DWG. NO. REV.

6-012-B026

13

MODEL 1181T SECTION 2.0

INSTALLATION

FIGURE 2-6. 1181T FM Approved Explosion Proof Installation

DWG. NO. REV.

1400155 C

14

15

3.1 DESCRIPTION OF CONTROLS

3.1.1 Internal Span Multiplier,R54, located on the
temperature PCB. The internal Span Multiplier is a 20-

turn potentiometer which provides a coarse span and is
continuously adjustable from X1 to X10. The Internal
Span Multiplier is used in conjunction with the Range
Factor Switch. This adjustment is accessed by removing
the cover on the CIRCUIT SIDE of the Transmitter
(Figure 3-3).

3.1.2 External Zero Pot, R18, located on the driver
PCB. The External Zero is a 20-turn potentiometer used

for fine adjustment of the 4.0 mA isolated current output.
This adjustment is accessed by removing the Serial Tag
on the side of the housing and is designated by a "Z"
(Figure 3-1).

3.1.3 External Span Pot, R16, located on the driver
PCB. The External Span is a 20-turn potentiometer used

for fine adjustment of the 20.0 mA isolated current output.
This adjustment is accessed by removing the Serial Tag
on the side of the housing and is designated by an "S"
(Figure 3-1).

3.1.4 Range Factor Switch, located on the input PCB.

The Range Factor Switch is comprised of three dip
switches: S1, S2, and S3. Different full scale ranges may
be obtained by setting the switches to the desired posi­tions. The Range Factor Switches determine the maxi­mum available full scale conductivity range (Figure 4-1).

3.1.5 Range Jumper, located on the driver PCB.

This jumper increases the range of the Model 1181T. For
a multiplier of X1, place the jumper in W2 position. For a
multiplier of X10 place the jumper in W3 position (Figure
3-4).

MODEL 1181T SECTION 3.0

DESCRIPTION OF CONTROLS

SECTION 3.0

DESCRIPTION OF CONTROLS

3.1.6 Temperature Slope Adjustment, R46, located

on the temperature PCB. Each conductive solution has

its own set of conductivity vs percent concentration
curves which change with temperature change. The
function of the temperature slope adjustment is to cali­brate the temperature compensation curve to a specific
solution over the operating temperature range. The con­ductivity indication is corrected along the calibrated tem­perature slope to a 25°C reference temperature. When
the temperature slope adjustment is set to 0% /°C, the
temperature compensator is disabled. It is very impor­tant then that the process temperature be at or near
25°C (Figure 3-3).

3.1.7 Analog/LCD Operation Jumper, W1, located on

the transmitter PCB. When the jumper is in the W1 posi-

tion, the 1181T will operate only with an analog meter or
as a blind unit. But when the jumper is in the opposite
position or is removed, the 1181T will operate only with
an LCD (Figure 3-5).

3.1.8 Sensor Zero, R11, located on the driver PCB.

The Sensor Zero potentiometer is used to offset cable
resistance measured as conductivity. The Sensor Zero is
used upon completion of all field wiring and prior to fine
calibration of the 4.0 mA output with the External Zero
(Figure 3-4).

16

MODEL 1181T SECTION 3.0

DESCRIPTION OF CONTROLS

FIGURE 3-1. External Span And Zero

FIGURE 3-2. Model 1181T PCB Stack

17

MODEL 1181T SECTION 3.0

DESCRIPTION OF CONTROLS

FIGURE 3-4. Driver Circuit Board

FIGURE 3-5. Transmitter Circuit Board

FIGURE 3-3. Temperature Circuit Board

DWG. NO. REV.

22933-01 D

DWG. NO. REV.

22932-01 D

DWG. NO. REV.

22931-01 G

18

MODEL 1181T SECTION 2.0

INSTALLATION

FIGURE 3-6. Signal Input Circuit Board

DWG. NO. REV.

22934-01 G

19

MODEL 1181T SECTION 4.0

CONFIGURATION

4.2 RANGE SELECTION

The sequence for changing the full scale measurement
range of the Model 1181T is shown on a matrix. The
matrix is accessed by removing the housing cover on
the CIRCUIT SIDE of the Transmitter.

IMPORTANT NOTE

As an alternative to the following
instructions, see Table 4-1.

4.1 GENERAL

The Model 1181T is factory calibrated to measure
0-5,000 microsiemens/cm corresponding to 4-20mA and
the temperature slope adjustment is set at 0%.
The optional LCD display is calibrated to 0-100%
corresponding to 4-20 mA.

NOTE

1 microsiemen/cm (µS/cm)=1 micromho/cm (µmho/cm)

1 millisiemen/cm (mS/cm)=1000 µmho/cm

NOTE

Do not attempt to adjust any sealed adjust­ment pots.

SECTION 4.0

CONFIGURATION

TABLE 4-1.

Full Scale Readings of the 1181T in Microsiemens/cm with Various Probe Constants

SENSORS SWITCH INTERNAL JUMPER

226 225 222 SPAN

228 POT W-2 W-3

S3 S2 S1 X1 X5 X10 X1 X10

40 250 600 X X X

80 500 1,200 X X X
200 1,250 3,000 X X X
400 2,500 6,000 X X X
800 5,000 12,000 X X X X

2,000 12,000 30,000 X X X
4,000 25,000 60,000 X X X X

8,000 50,000 120,000 X X X X
40,000 250,000 600,000 X X X X
80,000 500,000 1,200,000 X X X X

X0.4 X2.5 X6.0 PROBE CONSTANT

Switch is closed where X appears
Span Pot is set to X1, X5 or X10 where X appears.
Jumper W-2 or W3 is selected where X appears
External Span can multiply conductivity by 2.

20

4.2 RANGE SELECTION (CONTINUED)

The first three columns of the matrix list the sensor types
available. Listed beneath each are the maximum values
obtainable by that sensor group.

Switchsettings required to achive each maximum range
are given in the next three columns. The X denotes a
closed switch. Nothing in the column indicates the
switch is open.

The Internal span pot positions to achieve the range are
indicated in the next three columns. An X means to posi­tion the span pot in that position as shown on the matric
cover.

The Jumpers located on PCB #2 should be connected
where the X is in the row of the maximum range desired.

Example: Starting at the left side of the matrix:

Sensor selected: Model 228

Full Scale range desired: 50,000 Microsiemens/cm (50K)

Set up switches, pot and jumpers as follows:

S1 - closed
S2 - open
S3 - closed

Internal Span

Multiplier (R54): Adjust to X10 position.

Jumpers for X1 range: W-2 across both pins. W-3

jumper on only one pin.

NOTE:

Final adjustment of the Internal Span
Multiplier should be accomplished prior to
fine calibration of the 20 mA output with
the External Span on full scale calibration
of the Transmitter.

MODEL 1181T SECTION 4.0

CONFIGURATION

FIGURE 4-1. Model 1181T Matrix Cover

DWG. NO. REV.

40118141 A

21

FIGURE 4-2. Digital Display

4.3 DIGITAL DISPLAY

The digital display is factory calibrated to indicate
0-100% corresponding to 4-20mA and is provided with
independent zero and span potentiometers.

The LCD is a three and a half digit display and may be
calibrated in engineering units (Conductivity) to indicate
from 000 to 1999.

A decimal point switch is provided and may be accessed
by removing three cover screws and the cover. The dec­imal point switch is located below and to the right of the
LCD display. The dip switches are designated s1, s2, and
s3. The decimal point adjustment is as follows:

To calibrate the LCD display, adjust the zero potentiome­ter for 000 at 4.0 mA output and the span potentiometer
for the full scale conductivity range at 20.0 mA output.

Decimal Point Position

s1 s2 s3

1999 open open open

199.9 open open closed

19.99 open closed open

1.999 closed open open

MODEL 1181T SECTION 4.0

CONFIGURATION

DWG. NO. REV.

40118140 A

22

D. Take a grab sample and measure its conductivity at
the minimum process temperature in the laboratory.
Record the conductivity value and the temperature.

E. Elevate the temperature of the grab sample to the
maximum process temperature. Record the conductivity
value and the temperature.

F. Then, calculate % slope adjustment by using the
following formula:

Conductivity T

max

% SLOPE/°C=

(

Conductivity T

min

–1

)

³T

X100

Where: Conductivity T

max

is the conductivity at the

maximum process temperature, Conductivity T

min

is the
conductivity at lower process temperature, and the ³T is
the difference between the maximum temperature and
minimum process temperature.

EXAMPLE:

(

45K

–1

)

X100

35K

% SLOPE/°C=

60–50=10

=2.8%/°C

G. Set the Temperature Slope Adjustment, R46, to the
correct slope adjustment as determined by computing
the formula in Step F above.

4.4 TEMPERATURE SLOPE ADJUSTMENT

Following are the typical temperature slopes for Acids,
Bases and Salts. For greater accuracy the temperature
slope for an unknown solution may be determined in a
laboratory with a portable conductivity analyzer or for
more precision with the Model 1181T and associated
sensor.

Acids: 1.0 - 1.6% / °C
Bases: 1.8 - 2.2% / °C
Salts: 2.2 - 3.0% / °C
Neutral Water: 2.0% / °C

The operational limits of the Model 1181T with regard to
measuring range vs maximum temperature slope adjust­ment at various operating temperatures is shown in the
following table.

If the process temperature is expected to vary more than
10°C, adjust the SLOPE ADJUST as follows:

A. With the sensor immersed in the grab sample at the
minimum process temperature allow approximately 15
minutes for the sensor to stabilize. After the temperature
has stabilized, record the conductivity reading.

B. Elevate the grab sample temperature to the maximum
process temperature.

C. Allow the temperature to stabilize and set the temper­ature SLOPE ADJUSTMENT, R46, so the conductivity
reading is the same at the higher temperature as it was
at the lower temperature. If it is impractical to immerse
the sensor in a beaker or elevate the temperature of the
grab sample, then:

Range/Scale 25°C 50°C 75°C 100°C 125°C 150°C 175°C 200°C

1 Siemens/cm 4% 4% 2% 1.3% 1% N/A N/A N/A

0.5 Siemens/cm 4% 4% 4% 4% 3% 2.2% 2% 1.7%

0.2 Siemens/cm 4% 4% 4% 4% 4% 3.2% 2.6% 2.2%

All Others 4% 4% 4% 4% 4% 3.2% 2.6% 2.2%

TABLE 4-2. Operational Limits vs. Slope

MODEL 1181T SECTION 4.0

CONFIGURATION

23

MODEL 1181T SECTION 5.0

START UP AND CALIBRATION

The Model 1181T may be calibrated by (1) using either a
conductivity standard or a sample of the process, (2) in­situ calibration by grab sample analysis, or (3) calibra­tion using decade box or resistors to simulate
conductance. Calibration using a process sample will
provide the greatest accuracy.

5.1 CALIBRATION USING A CONDUCTIVITY
STANDARD OR PROCESS SAMPLE

1. Complete all field wiring as described in Section 2.0.

2. Configure the Transmitter as described in Section

4.0.

3. With the Sensor in Air

A. Adjust the Sensor Zero, R11, for coarse calibra-

tion of the 4.0 mA current output.

B. Adjust the External Zero for fine calibration of the

4.0 mA current output.

C. Optional, Adjust the LCD Zero Potentiometer,

R8, for 000.

4. Place the Sensor in a container filled with a
Conductivity Standard or Process Sample.

NOTE

All sides of the sensor should be at least
one sensor diameter from the walls of the
sample container. It is important that the
sensor position in the sample container
approximate the actual mounting arrange­ment because the sensor cell constant is
affected by its immediate environment.

Insure no air bubbles are trapped in the
center hole.

5. Adjust the Internal Span Multiplier, R54, for coarse
adjustment of the output current value in milliamps of
the known Conductivity Standard or to the measured
value of the process sample.

mA output =

C

S

(

C

FS

X16

)

+4

Cs= Conductivity of Standard Solution or Process

Sample.
Cfs= Full Scale Conductivity Range Selected.

EXAMPLE: The selected full scale conductivity range is
5000 microsiemens/cm and the standard solution used is
2000 microsiemens/cm.

mA Output =

(

2000

X16

)

+ 4 = 10.4 mA

5000

6. Adjust the Temperature Slope potentiometer, R46, to
the calculated slope value.

7. Fine Adjust the current output calculated in Step 5
with the External Span.

8. Optional; Adjust the LCD display Span potentiome­ter, R4, either to (1) a percent indication or (2) to the
value of the Conductivity Standard or the measured
conductivity value of the process sample.

LCD or Analog Display =

C

S

(

C

FS

)

X100

EXAMPLE:

(

2000

)

5000

X100 = 40%

9. Install the Sensor into the process. Final calibration
may be done with the External Span to a process
grab sample.

SECTION 5.0

START UP AND CALIBRATION

24

MODEL 1181T SECTION 5.0

START UP AND CALIBRATION

5.2 IN-SITU CALIBRATION BY
GRAB SAMPLE ANALYSIS

1. Complete all field wiring as described in Section 2.0.

2. Configure the Transmitter as described in Section

4.0.

NOTE

If extension cable is used, disconnect the
sense wire on the sensor side of the
junction box. If extension cable is not
used, disconnect the sense wire at the
transmitter.

3. Adjust the External Zero for fine calibration of the 4.0
mA current output.

4. Optional; Adjust the LCD Zero Potentiometer, R8, for

000.

5. Re-connect the sensor sense wire at the junction
box.

6. Take a grab sample of the process and measure its
Conductivity value using a calibrated portable ana­lyzer having a reference temperature of 25°C. Note
the Transmitter Indication for reference.

CAUTION

Older portables may have a reference tem­perature of 18°C which will cause variance
in the measured value.

7. Adjust the Internal Span Multiplier, R54 for coarse
adjustment of the current output in milliamps to the
measured value of the process sample.

C

GS

mA Output =

(

C

FS

X16

)

+4

Where: C

GS

= Calibration value or the Grab Sample

conductivity.

C

FS

= Full Scale Conductivity.

EXAMPLE:

(a) The 1181T Conductivity reading at sampling and

prior to calibration has not changed.

Grab Sample Conductivity = 8,500 microsiemens /cm

Full Scale Conductivity = 10,000 microsiemens/cm

8500

mA Output =

(

10,000

X16

)

+4 = 17.6 mA

If the Transmitter Indication has changed from the time
the grab sample was taken, use the following formula to
calculate for the calibration value.

(C

M

x C2)

CGS=

________

C

1

Where:

CGS= True Grab Sample Conductivity

CM= Grab sample conductivity measured by a cali-

brated lab meter.

C1= Conductivity reading on the 1181T when the grab

sample was taken.

C

2

= Conductivity reading on the 1181T just prior to

making span adjustment.

8. Adjust the Temperature Slope potentiometer, R46, to
the calculated slope value.

9. Adjust the External Span for fine calibration of the
current output in milliamps to the measured value of
the process sample.

10. Optional; Adjust the LCD display Span potentiome­ter, R4, either to (1) a percent indication or (2) to the
value of the Conductivity Standard or to the meas­ured conductivity value of the grab sample.

LCD or Analog Display =

(

C

GS

)

X100

C

FS

The analog of LCD display should read:

(

8500

)

X100 = 85%

10000

25

MODEL 1181T SECTION 5.0

START UP AND CALIBRATION

5.3 FULL SCALE CALIBRATION USING A
DECADE BOX OR RESISTORS

The 1181T transmitter may be calibrated by using a
decade box or resistors to simulate a full scale conduc­tivity indication. A decade box or resistor is wired in
series with a wire looped through the toroids as shown
in Figure 5-1. This method may be used for all sensors
including the Model 222 Flow Through Sensor.

NOTE

Sensors must be out of the process, and
flow tubes must be empty prior to perform­ing this procedure.

Following are the approximate cell constants by Model
Number. The cell constant is used in calculation of full
scale resistance.

Model Number

Cell Constant (K)

222 6.00
224 0.81
225 3.00
226 0.40
228 2.50

Cell Constant X1,000,000

= Resistance in Ohms

Max. Conductivity Selected

EXAMPLE:

1. Selected Full Scale Range, 2000 micro-siemens/cm

Sensor Model: 225

3.00 X 1,000,000
= 1,500 Ohms

2000

2. Selected Full Scale Range, 100,000
microsiemens/cm

Sensor Model: 228

3.00 X 1,000,000
= 30 Ohms

100,000

CAUTION

Is the sensor’s metal installation connector
in contact with the measured process
during normal installation? If so, to avoid
an offset error during a bench calibration
(sensor in air), the 1181T transmitter and
the sensor’s (225; 226-81 or 82; 228-20)
metal installation connector must be
grounded to the same potential.

FIGURE 5-1. 1181T Calibration Set-Up

WIRE

26

MODEL 1181T SECTION 6.0

THEORY OF OPERATION

SECTION 6.0

THEORY OF OPERATION

6.1 THEORY OF OPERATION

Conductivity is defined as “conductance” per unit length
of a medium. It is measured electrically using the rela­tionship I = GV, where “G” is the conductance, “V” is the
reference voltage and “I” is the resultant current, which
is directly proportional to the conductance. The Model
1181T works according to this principle.

The toroids are used as two independent transformers
that have a common turn, which is the path of the liquid
being measured. The transmitter toroid (driver) induces
a voltage across the toroid winding, divided by the num­ber of turns in the winding. This voltage, times the con­ductance, results in a current that is equal to the current
in the liquid loop divided by the number of turns in the
windings of the toroid. The result is I=G*V(N1*N2),
where N1 equals the number of turns of the transmitter
toroid (driver) and N2 is equal to the number of turns of
the receiver toroid.

The Transmitter Board (No. 1 or bottom board) of the
Model 1181T stack, produces the reference voltage for
the instrument. A shunt regulator in a bridge circuit with
a reference element VR1 (LM385), amplifier AR1 and a
Vmos pass transistor, are used to maintain a 7.5 volt

positive reference supply. The voltage is used in the
conductance measurement. All the excess current pass­es through this shunt circuit, which is designed to handle
up to 30 mA before the protection diodes go to conduc­tion. By measuring the voltage across R1 the current
can be determined.

Other items found on this board include a triple set of

8.2 volt zeners for intrinsically safe protection, a current
diode (CR1) used for start-up current, and Q2 which is
P-channel Vmos transistor which regulates the current in
the loop. Jumper W1 is open when the transmitter has
an LCD option and closed when either Blind or Analog
versions are used.

The Driver Board (No. 2 board) generates the power
used to drive the transmitter toroid. A multivibrator (U2)
runs at a frequency of 8K Hertz. The IC, U1, drives
transformer T1 in a push-pull fashion simultaneously
generating a negative supply voltage at CR5, CR6, C10
and C11. The capacitors are protected by R12 and R13.
Transformer T1 steps the signal down to drive the low
impedance of the toroid and also allows for a X10 multi­plier. The transformer provides an important

FIGURE 6-1. Toroidal Conductivity Principle

27

MODEL 1181T SECTION 6.0

THEORY OF OPERATION

scaled by the pot R54, from X1 to X10, before it is
processed by the temperature compensation circuit.

The Signal Input Board (No. 4 or top board) processes
the current from the receiver toroid. This current is less
than one microamp peak-to-peak on the lowest conduc­tivity ranges. The circuit is a differential, low-powered,
high-speed, tight-looped, current-to-voltage amplifier,
with op-amp AR8 used to bias the circuit. The square­wave current from the toroid passes through transistor
Q5 and appears across a resistor string for scaling. The
full scale signals of 500, 1000 and 10,000 micromhos
may be selected. The output is buffered by Q9 to drive
the demodulator on board No. 3.

FIGURE 6-2. Model 1181T Operation Block Diagram

6.1 THEORY OF OPERATION (CONTINUED)

isolation function enabling terminal TB2-3 to be used for
two signals (one for transmitter toroid return and the
other for an RTD input for temperature compensation.
The amplifier AR3 drives the P-channel Vmos transistor
on board No. 1. The external zero and span pots are
also located on this board at AR3.

The Temperature Board (No. 3 board) is the temperature
compensation board. It normalizes conductivity to a
25°C reading. The temperature compensation is
adjustable from 0 to 4 percent per degree Centigrade
with pot R46. Pots R34 and R44 are used to calibrate
the temperature circuit. Also found on this board is the
input signal demodulator which is driven synchronously
with the toroidal drive circuit. The resultant voltage is

28

MODEL 1181T SECTION 6.0

THEORY OF OPERATION

6.2 CIRCUIT DESCRIPTION (Figure 6-3)

VR1 and the Vmos pass transistor are used to maintain
the reference voltage (peak voltage of the square wave)
at 7.5 volts D.C.

This voltage is sent to the multivibrator U2, which cre­ates a square wave (8K Hertz frequency).

This square wave is passed to the power voltage driver
V1 and is stepped-up by T1. It is then sent to the driver
toroid.

The voltage through the driver coil induces a current into
the process solution.

The current of the process induces a current flow in the
receiver (pick-up) coil that is proportional to the conduc­tivity of the process solution. This current is then differ­entially amplified by Q6, Q7, Q8 and Q9.

AR8 biases the circuit and Q5 passes the current, which
is adjusted for ranges of 500, 1000 and 10,000 by a
microswitch selection to a voltage divider (R64, R65,
R66 and R67).

This adjusted current is passed through Q9, which is a
buffer to the demodulator U4, AR6-D.

AR6-D and U14 converts the 8K hertz current to a direct
current voltage which is still proportional to the conduc­tivity of the process fluid.

The voltage is further adjusted by the setting of R54,
which is the span factor adjust from X1 to X10.

The voltage is then passed to the output AR6-C. The
voltage at that point is modified, based on the input from
AR6-B (temperature compensation circuit).

As the resistance of the temperature compensator (T.C.)
at the sensor changes with respect to the process
temperature (input at TB-3), it causes a change to the
feedback loop gain of the T.C. circuit. This, in turn,
changes the gain of the T.C. circuit, which causes
a change in the voltage output at AR6-C.

The T.C. corrected voltage output from AR6-C is further
adjusted by the External Span and Zero Pots (R16
and R18), then passed from AR3 to the gate of Q2
(P-channel Vmos).

As the voltage changes at the gate of Q2 with respect to
conductivity/temperature, Q2 changes current
flow through the loop. This provides a 4 to 20 milliamp
output.

29

MODEL 1181T SECTION 6.0

THEORY OF OPERATION

FIGURE 6-3. Model 1181T Schematic

DWG. NO. REV.

2400204 H

30

MODEL 1181T SECTION 7.0

DISASSEMBLY/REASSEMBLY PROCEDURE

SECTION 7.0

DISASSEMBLY/REASSEMBLY PROCEDURE

7.1 DISASSEMBLY PROCEDURE

Disconnect the power to the transmitter prior to dis­assembly. (Refer to Figure 9-1 for item numbers also
see Figure 3-1).

1. Remove covers (1) and (18) or meter housing cover
(19) from housing (3). Save O-rings (2); discard if
damaged.

2. Loosen screws retaining the serial label, and then
rotate to gain access to the Span and Zero pots.

3. Align the Span and Zero adjusting screws (4), so the
slots are horizontal, pointing end cap to end cap.

4. In circuit side of housing (3) remove the circuit board
retaining screws, washers and matrix cover (10). The
matrix cover is secured to screws by nylon split
washers. Remove the screws in equal increments,
so the matrix cover is not damaged.

5. Pull straight out on the signal conditioning board
assembly (9) to remove circuit boards from hous­ing (3).

6. To separate the individual boards, remove the retain­ing screw located on the terminal side of the trans­mitter board (6).

7. Remove each printed circuit board assembly by
pulling straight out from their respective connectors.

7.2 REASSEMBLY PROCEDURE

1. Assemble the circuit board assemblies (6, 7, 8, 9) by
first aligning the connectors with the respective pins,
and then pushing straight in. Install screw which
holds circuit board assemblies together.

2. Align the Zero and Span adjusting screws (4) on the
housing (3) to the horizontal position, slots pointing
end cap to end cap (see Figure 4-1).

3. Align the Zero and Span potentiometers located on
the driver circuit board (7) to the horizontal position,
with blades perpendicular to PCB's (6) and (7).

4. Place the circuit board assemblies (6, 7, 8, 9) into
housing by first aligning the connector pins with the
terminal receptacles in the base of the housing (3)
and then pushing straight in on the signal condition­ing board (9).

5. Install the matrix cover (10) and secure with screws
and washers. The matrix cover is secured to the
screws with nylon split washers, so install the screws
in equal increments, so the matrix cover is not dam­aged.

6. Inspect the thread connections on housing (3) to
make sure five undamaged threads will fully engage.

7. Replace O-rings (2) on housing (3). Use new
O-rings if the old ones were damaged.

8. Install covers (1, 18) or meter housing (19) on trans­mitter housing (3).

9. Apply power to the transmitter and perform the
appropriate calibration procedure if necessary.

31

MODEL 1181T SECTION 8.0

TROUBLESHOOTING

SECTION 8.0

TROUBLESHOOTING

8.1 GENERAL

This section covers the trouble-shooting and mainte­nance instructions for the Model 1181T. This transmitter
has no moving parts and requires minimum mainte­nance. Procedures for calibrating the Model 1181T is
given in Section 5.0 and generally the only operation
type "maintenance" required to keep the units in good
operating condition.

NOTE

If downtime is of critical concern, a full
complement of spare parts is recom-mend­ed. (See Section 9.0, spare parts).

8.2 TROUBLESHOOTING

Table 8-1 provides a general reference table for com­monly encountered problems and suggested actions to
be taken to correct those problems.

TROUBLE WHAT TO DO

Meter reads below zero and will not respond A. Check 24 VDC 1181T TB1-1,3.
to conductivity change.

B. Check all wire connections.
C. Check to see PCB's are fully seated into

1181T housing.

D. Make sure display, if LCD, wired with

correct polarity to TB1-2,3.
E. Go back through calibration.
F. Check Sensor Toroids. Refer to sensor manual

Meter pegged above full scale or full 20 mA output A. Check calibration.
no response to conductivity change.

B. Check the range configuration used

on the 1181T matrix.
C. Replace PC Board stack.

Meter output cycles from zero to A. Check resistance of T.C. in probe.
above full scale output and then back to zero again. Should be 3,000 ohms at 25°C.
This is done like a metronome.

B. Check crimps on spade lug connectors T.C.
C. Replace probe.

Meter rests at zero with slight oscillation. A. Check probe wire crimps on spade lugs to

TB2-1 TB2-3.
B. Replace sensor (pick up coil open).

Meter output oscillates around 10% of full scale– A. Check crimp single white wire to TB2-3 shield.
No response to conductivity change.

B. Replace probe.

NOTE: When slope adjustment is set to below 1%
problem goes away.

TABLE 8-1. Troubleshooting Guide

32

Item No. Part Number Description Qty.

1 3002425 Cover (for Blind Model) 1

2 2002604 O-ring Kit 1

Consists of:
99550136 O-ring 12

3 2002528 Housing (Includes #4 below) 1

4 2002598 Adjustment Screw Kit 1

Consists of:
9160299 Retaining Ring 4
9550137 O-ring 2
3002422 Screw, Adjustment 2

5 2002605 O-ring Kit 1

Consists of:
9550137 O-ring 12

6 22931-01 Transmitter PCB (Blind/Analog) 1

22931-02 Transmitter PCB (LCD) 1

7 22932-01 Conductivity Driver PCB 1

8 22933-01 Temperature PCB 1

9 22934-01 Signal Input PCB 1

10 22803-02 Matrix Cover Kit 1

Consists of:
32855-01 Cover, Matrix 1
9600634 Screw, Short 1
9600642 Screw, Long 1
9910404 Washer, Nylon (Split) 2
9910600 Washer, Flat 2
9910610 Washer, Lock 2

19 2002518 Meter Cover Kit 1

Consists of:
3002429 Housing 1

20 9550135 O-ring 12

21 3002421 Window 1

32491-00 Ring, Retainer 1

18 3002468 Cover, Tall (PCB Side) 1

12A 23122-00 Meter,LCD (Code 06) 1

13 2002599 Meter Sleeve Kit (Codes 01, 03) 1

Consists of:

Sleeve, Analog 1

3002433

9560185 Nut, Hex 1

9731003 Set Screw, Short 4

9730816 Set Screw, Long 1

32822-00 Sleeve for LCD Meter 1

13 23110-01 Plug In Analog Meter Retrofit Kit (Code 01)

23110-07 Plug In Analog Meter Retrofit Kit (Code 03)

SECTION 9.0

SPARE PARTS

9.1 SPARE PARTS. (Refer to Figure 9-1 for the following spare parts list for the Model 1181T.

TABLE 9-1. Model 1181T Two-Wire Transmitter Spare Parts

MODEL 1181T SECTION 9.0

SPARE PARTS

33

Item No. Part Number Description Qty.

12B 9170163 Analog Meter, Plug In (Code 01) 1

9170167 Analog Meter, Plug In (Code 03) 1

14 32955-00 Mounting Plate 1

9600606 Mounting Plate Screws 2

15 32996-00 Insulator 1

17 32961-00 Terminal Plug In Adaptor Screws 2

16 32997-00 Retainer Clip 1

MODEL 1181T SECTION 9.0

SPARE PARTS

TABLE 9-1. Spare Parts Continued

FIGURE 9-1. Model 1181T Two-Wire Transmitter Parts

34

MODEL 1181T SECTION 10.0

RETURN OF MATERIAL

SECTION 10.0

RETURN OF MATERIAL

10.1 GENERAL

To expedite the repair and return of instruments, proper
communication between the customer and the factory is
important. Before returning a product for repair, call 1­949-757-8500 for a Return Materials Authorization
(RMA) number.

10.2 WARRANTY REPAIR

The following is the procedure for returning products still
under warranty.

1. Contact the factory for authorization.

2. To verify warranty, supply the factory sales order
number or the original purchase order number. In the
case of individual parts or sub-assemblies, the serial
number on the mother unit must be supplied.

3. Carefully package the materials and enclose your
“Letter of Transmittal”. If possible, pack the materials
in the same manner as it was received.

4. Send the package prepaid to:

Rosemount Analytical Inc., Uniloc Division
2400 Barranca Parkway
Irvine, CA 92606

Attn: Factory Repair

Mark the package:

Returned for Repair RMA No. _______________

Model No. ______________

10.3 NON WARRANTY REPAIR

1. Contact the factory for authorization.

2. Carefully package the materials and enclose your
“Letter of Transmittal”. Include a purchase order
number and make sure to include the name and tele­phone number of the right individual to be contacted
should additional information be needed.

4. Do Step 4 of Section 10.2.

NOTE

Consult the factory for additional infor­mation regarding service or repair.

WARRANTY

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, such as glass electrodes,

membranes, liquid junctions, electrolyte, o-rings, catalytic beads, etc., and Services are warranted for a period of 90
days from the date of shipment or provision.

Products purchased by Seller from a third party for resale to Buyer ("Resale Products") shall carry only the 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, EXPRESS OR IMPLIED, AS TO MERCHANTABILITY, FIT­NESS FOR PARTICULAR PURPOSE, OR ANY OTHER MATTER WITH RESPECT TO ANY OF THE GOODS OR SERVICES.

RETURN OF MATERIAL

Material returned for repair, whether in or out of warranty, should be shipped prepaid to:

Emerson Process Management

Liquid Division

2400 Barranca Parkway

Irvine, CA 92606

The shipping container should be marked:

Return for Repair
Model

_______________________________

The returned material should be accompanied by a letter of transmittal which should include the following information (make a
copy of the "Return of Materials Request" found on the last page of the Manual and provide the following thereon):

1. Location type of service, and length of time of service of the device.

2. Description of the faulty operation of the device and the circumstances of the failure.

3. Name and telephone number of the person to contact if there are questions about the returned material.

4. Statement as to whether warranty or non-warranty service is requested.

5. Complete shipping instructions for return of the material.
Adherence to these procedures will expedite handling of the returned material and will prevent unnecessary additional charges

for inspection and testing to determine the problem with the device.

If the material is returned for out-of-warranty repairs, a purchase order for repairs should be enclosed.

Credit Cards for U.S. Purchases Only.

The right people,
the right answers,
right now.

ON-LINE ORDERING NOW AVAILABLE ON OUR WEB SITE

http://www.raihome.com

Emerson Process Management
Liquid Division

2400 Barranca Parkway
Irvine, CA 92606 USA
Tel: [phone]
Fax: [phone]

http://www.raihome.com

© Rosemount Analytical Inc. 2003