Georg Fischer 2850 Operating Manual

Signet 2850 Conductivity/Resistivity Sensor Electronics (PVDF)

*3-2850.090-1*

3-2850.090-2 Rev. C 03/15

Operating Instructions

English

3-2850-51, 3-2850-52

with ¾-in. adapter

3-2850-61, 3-2850-62, 3-2850-63

with Universal adapter

3-2850-51-XXV(D), 3-2850-52-XXV(D)

PVDF Integral System

Description

• Signet 2850 Conductivity/Resistivity Sensor Electronics provides either a two-wire
4 to 20 mA output or Digital (S3L) format.

• The 4 to 20 mA output models provide eight ranges for each electrode cell constant,
plus the ability to invert each range.

• The EasyCal feature allows the devices to automatically recognize standard
conductivity test solution values for simple fi eld calibration.

• The Conductivity Sensor provided with integral systems will have its custom cell
constant information programmed into the electronics at the factory to provide a
2% sensor accuracy. See page 6 for details.

Table of Contents

Description ............................................................................................ 1

Dimensions ........................................................................................... 1

Warranty Information ............................................................................ 2

Product Registration ............................................................................. 2

Safety Information................................................................................. 2

Specifi cations........................................................................................ 2

Conductivity Sensor Dimensions .......................................................... 3

Operating Range Chart......................................................................... 3

In-Line Installation................................................................................. 4

Tank Installation .................................................................................... 4

4 to 20 mA Wiring ................................................................................. 5

Digital (S3L) Wiring ................................................................................ 5

Dual Input Wiring (Dual Digital (S3L) Output) ........................................ 5

Cell Constant Selection ........................................................................ 6

Range Selection for 4 to 20 mA Output ................................................ 7

Calibration............................................................................................. 8

EasyCal ................................................................................................ 8

Dual Input Calibration ........................................................................... 8

Maintenance ......................................................................................... 9

Troubleshooting .................................................................................... 9

Electronic Certifi cation ........................................................................ 10

Ordering Information ........................................................................... 12

• English

• Deutsch

• Français

• Español

• Italiano

Dimensions

2850-51, -52 Integral mount 2850-61, -62, -63 Universal mount

95 mm

3.74 in.

85 mm

3.34 in.

95 mm

3.74 in.

82 mm

3.24 in.

Warranty Information

Specifi cations

Refer to your local Georg Fischer Sales offi ce for the most
current warranty statement.

All warranty and non-warranty repairs being returned must
include a fully completed Service Form and goods must be
returned to your local GF Sales offi ce or distributor.
Product returned without a Service Form may not be
warranty replaced or repaired.

Signet products with limited shelf-life (e.g. pH, ORP, chlorine
electrodes, calibration solutions; e.g. pH buffers, turbidity
standards or other solutions) are warranted out of box but not
warranted against any damage, due to process or application
failures (e.g. high temperature,
mishandling (e.g. broken glass,

chemical poisoning, dry-out) or

damaged membrane, freezing

and/or extreme temperatures).

Product Registration

Thank you for purchasing the Signet line of Georg Fischer
measurement products.

If you would like to register your product(s), you can now
register online in one of the following ways:

• Visit our website www.gfsignet.com.
Under Service and Support click on

Product Registration Form

• If this is a pdf manual (digital copy),

click here

Safety Information

1. Depressurize and vent system prior to installation or removal.

2. Confi rm chemical compatibility before use.

3. Do not exceed maximum temperature/pressure specifi cations.

4. Wear safety goggles or faceshield during installation/service.

5. Do not alter product construction.

6. When using chemicals or solvents, care should be taken
and appropriate eye, face, hand, body, and/or respiratory
protection should be used.

Caution / Warning / Danger

Indicates a potential hazard. Failure to follow all warnings
may lead to equipment damage, injury, or death

Electrostatic Discharge (ESD) / Electrocution Danger

Alerts user to risk of potential damage to product by ESD,
and/or risk of potential of injury or death via electrocution.

Personal Protective Equipment (PPE)

Always utilize the most appropriate PPE during
installation and service of Signet products.

Pressurized System Warning

Sensor may be under pressure, take caution to vent
system prior to installation or removal. Failure to do so
may result in equipment damage and/or serious injury.

Note / Technical Notes

Highlights additional information or detailed procedure.

General

Compatible Electrodes ............. Any Signet Conductivity/

Resisitivity electrode

(2818-2823, 2839-2842)

Temperature Compensation .....PT-1000 RTD (2% per °C)

Pure Water Compensation ....... Auto-switching when using

0.01 cell and raw conductivity

value < 0.5 S

EasyCal

Automatic recognition of the following conductivity values:

• 146.93 S, 1408.8 S, 12856 S (@ 25 °C)
(Test solutions per ASTM D1125-95)

• 10 S, 100 S, 200 S, 500 S, 1000 S, 5000 S, 10,000 S,

50,000 S, 100,000 S (@ 25 °C)

Power

• 12 to 24 VDC (4 to 20 mA output)

• 5 VDC ±5% regulated, 3.0 mA max. for Digital (S

3

L) output

(Reverse polarity and short circuit protected)

Digital (S

3

L) Output ................. Serial ASCII, TTL level 9600 bps

Accuracy

• Conductivity ..........................±2% of reading

• Temperature ..........................±0.5 °C

Resolution

• Conductivity ..........................0.1% of reading

• Temperature ..........................< 0.2 °C

Update Rate

• Single Input models ..............< 600 ms

• Dual Input models .................< 1.2 s

Current Output

Field-selectable ranges. Factory set span:

• 0.01 cell

(2818, 2819, 2839)

.. 4 to 20 mA = 0 to 100 S

• 0.10 cell (2820, 2840) ........... 4 to 20 mA = 0 to 1000 S

• 1.0 cell (2821, 2841) ............. 4 to 20 mA = 0 to 10,000 S

• 10.0 cell (2822, 2842) ........... 4 to 20 mA = 0 to 200,000 S

• 20.0 cell (2823) ..................... 4 to 20 mA = 0 to 400,000 S

Max. Loop Resistance .............. 50  @ 12 VDC

325  @ 18 VDC

600  @ 24 VDC

Accuracy ................................... ±2% of output span

Resolution.................................7 A

Update Rate .............................<600 ms

Error Indication ......................... 22 mA

3

Available data via Digital (S

L) Output

• Raw conductivity

• Calibrated conductivity

• Calibrated temperature-compensated conductivity

• Temp. Error Indication ........... Open input and out-of-range

diagnostics for temperature or

internal electronic error.

Environmental

Material ..................................... PBT

Enclosure Rating ...................... NEMA 4X/IP65

Operating Temperature .............-10 to 85 °C (14 to 185 °F)

Storage Temperature ................-20 to 85 °C (-4 to 185 °F)

Relative Humidity......................0 to 95%, non-condensing

Shipping Weight .......................0.75 kg (1.75 lb.)

Standards and Approvals

• CE, RoHS Compliant

• Manufactured under ISO 9001 for Quality,

ISO 14001 for Environmental Management and
OHSAS 18001 for Occupational Health and Safety.

China RoHS (Go to www.gfsignet.com for details)
This device complies with Part 15 of the FCC rules.

Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and
(2) This device must accept any interference received,

including interference that may cause undesired operation.

2

2850 Conductivity/Resistivity Sensor Electronics

Conductivity Sensor Dimensions

73.7 mm

2.90 in.

32.39 mm
(1.28 in.)

3-2839

3-2818

59.3 mm

2.33 in.

73.66 mm
(2.9 in.)

41.91 mm
(1.65 in.)

12.7 mm
(0.5 in.)

35.8 mm

1.41 in.

3-2840

4.6 m (15 ft)
cable (std)

152 mm
(6 in.)

12.7 mm
(0.5 in.)

3-2819, 3-2820, 3-2821

Operating Range Chart

107 mm
(4.2 in.)

49.5 mm
(1.95 in.)

21.5 mm

0.85 in.

41.9 mm

1.65 in.

¾ in. NPT

2820-x

20.3 mm
(0.8 in.)

2821-x

7.6 mm
(0.3 in.)

3-2841, 3-2842

26.8 mm

1.13 in.

T1 = 50 mm (2.0 in.)
T2 = 64 mm (2.5 in.)

152 mm
(6.0 in.)

126 mm
(5.0 in.)

3-2819, 3-2820, 3-2821

Sanitary

13 mm
(0.5 in.)

203 mm

8.0 in.

3-2823

89 mm

3.5 in.

(0.01 Cell)

0.010 μS

0

UPW @ 25°C

(0.10 Cell)

2818/2819/2839

0

USP

10 μS

.

2821/2841

(1.0 Cell)

2820/2840

1 μS

0

0.5 μS 20 μS

Bottled

(20.0 Cell)

(10.0 Cell)

100 μS

50 μS

.

Water

2823

2822/2842

1,000 μS 10,000 μS

Cooling Tower
Waste Waters

Deionization Regen. Chemicals

Alkali Cleaners, Acids/Bases

50,000 μS

200,000 μS

400,000 μS 200 μS 100,000 μS 0.055 μS

2850 Conductivity/Resistivity Sensor Electronics

3

In-Line Installation Tank Installation

While the 2850-5X and 2850-6X electronics cannot be
submerged, either model will accommodate tank installation.

Select any electrode with a 5 m (15 ft) cable. The cable may
be cut to length, but it CANNOT BE EXTENDED.

Most of the Conductivity/Resistivity electrodes
used with the 2850 can be installed into
standard 3/4 in. (NPT or ISO 7-R3/4) fi ttings.

The 2850-5X models are designed for
integral systems, where the electronics
are attached directly to the sensor.

The preferred installation for in-line applications directs fl ow
straight into the electrode. This confi guration reduces the
probability of entrapped air bubbles, and provides the best
continuous sampling of the fl uid content.

The universal adapter included with 2850-6X models can
be attached to the top of a tank or mounted to a surface near
the tank.

Adapt the 2850-5X models to tank installations by attaching a
clamp to the conduit.

If the electrode is mounted vertically in a tee, do not recess
the electrode orifi ces inside the tee. Mounting upside down
may help prevent air entrapment.

An oversized tee or fl ow cell may be helpful for inline
installations.

At least 4 threads (ANSI B1.20.1) must be engaged to meet
the pressure rating as published in the specifi cations.

Use the 2850-6X models for in-line installations where the
electronics must be separated from the electrode.

Conductivity electrodes with sanitary fl ange fi ttings must be
installed using this option.

4

2850 Conductivity/Resistivity Sensor Electronics

4 to 20 mA Wiring

Maximum length of 4 to 20 mA loop is 300 meters (1000 ft)

4

CTS

3
2

ON

1

3

V-

2
1

V+

SW1

4

CTS

3
2

ON

1

D3

to

9 VDC

4 20

4-20 mA Loop Output

26 VDC

Sensr Gnd
(SHIELD)

Temp. IN
(WHITE)

Signal RTN
(BLK)

Signal IN
(RED)

Digital (S3L) Wiring

The Digital (S
Signet 8900 Multi-Parameter Controller and
the Signet 9900 Transmitter.

Refer to the wiring sections of the 8900 or 9900
manual to determine cable length limitations.

IMPORTANT: Provide Earth Ground as

Note: The 2819-2823 and 2839-2842 sensors can

3

L) output is compatible with the

indicated by symbol.

connect directly to the 9900 via the 9900's
optional Direct Conductivity/Resistivity

I/O Module 3-8900.401-X

+5VDC (Black)

Frequency

Input

Freq. Input (Red)

1

GND (Shield)

+5VDC (Black)

Frequency

Input 2

Freq. Input 2 (Red)

Input

Input

S3L

OR
S3L

2

1

3

S L (Red)

GND (White/Shield)

+5VDC (Black)

3

S L (Red)

GND (White/Shield)

Analog Output 1

(if applicable)

Analog Output 2

(if applicable)

9900 S3L Input

3-8900.621C

1

2

3

4

5

6

7

8

9

10

11

+

12

-

13

+

14

-

SHLD

DATA

GND

V+

Module 3-9900.394 (159 001 699).

White
Red
Black

Dual Digital (S3L) Input Wiring

Dual Input is available on Digital (S3L) output
model 3-2850-63 only, for use with the Signet
8900 Multi-Parameter Controller.

Sensors may be the same or different cell
constants.

If the Dual Input model is used with a single
sensor, connect the sensor to Input 1 and set
all of the Input 2 switches to OFF (OPEN).

I/O Module 3-8900.401-X

+5VDC (Black)

Frequency

Input

Freq. Input (Red)

1

GND (Shield)

+5VDC (Black)

Frequency

Input 2

Freq. Input 2 (Red)

OR
S3L

Input

2

S3L

Input

1

3

S L (Red)

GND (White/Shield)

+5VDC (Black)

3

S L (Red)

GND (White/Shield)

Analog Output 1

(if applicable)

Analog Output 2

(if applicable)

3-8900.621C

1

2

3

4

5

6

7

8

9

10

11

+

12

-

13

+

14

-

Dual Input applications usually include one sensor with a smaller cell constant and
one sensor with a larger cell constant. Place the larger cell constant on Input 1.

This allows periodic recalibration of the larger cell by simply turning Input 2 OFF (OPEN).

Gnd

3

Data

2
1

V+

3

Gnd

2

Data

1

V+

SW1

SW1

CTS

ON

4
3
2

1

D3

3-9900.395

H COMM Module

CTS

ON

CTS

ON

4
3

Input 2

2

1

4
3

Input 1

2

1

D3

DC Power

Loop Voltage

Sensr Gnd
(SHIELD)

Temp. IN
(WHITE)

Signal RTN
(BLK)

Signal IN
(RED)

Sensor 2

Sensor 1

IMPORTANT: Provide Earth Ground as indicated by

symbol.

2850 Conductivity/Resistivity Sensor Electronics

5

Cell Constant Selection

S
1

2

3

4

ON

CTS

S
1

1

2

3ONCTS

Single Input 2850 Electronics
(2850-51, 2850-52, 2850-61, 2850-62)

• Single input models use only SW3.

• Use SW3 #1-3 to select the cell constant for the
fi rst sensor.

• Use SW3 #4 to disable the PT1000 Temp
Compensation function in the 2850 (as required for
USP applications).

• Recommended:

D3

W

ON

1

2

SW3

Input 1

Make all switch settings before supplying power.
Switch changes made after supplying power will
take 15 to 20 seconds before becoming effective.

Integral 2850 Systems (Single Input)

• The 2850-51-XX and 2850-52-XX are shipped from the factory with the custom cell
constant and temperature offset programmed into the single-input electronics.

• SW3 will be preset to "Custom cell constant".

• No additional modifi cations are required.

Replacing Integral System Electrode or Electronics

• When installing a new conductivity electrode or replacing System Electronics, the SW3
switches must be confi gured to select the appropriate cell constant.

• See Single Input section above.

• Leaving SW3 in the custom cell constant confi guration will effect accuracy.

• Use calibration standards to calibrate (see page 8).

Dual Input 3-2850-63 Electronics

• Switch banks SW3 and SW4 are used to select the
cell constant of the electrodes.

• Use SW3 #1-3 to select the cell constant for the
fi rst sensor.

• Use SW3 #4 to disable the PT1000 Temp
Compensation function in the 2850 (as required for
USP applications).
This disables the function for BOTH INPUTS.

• Use SW4 #1-3 to select the cell constant for the
second sensor.

W

D3

ON

1

2

SW3

Input 1 Input 2

• Set SW4 #4 to OPEN to disable Input 2.

• Recommended:
Make all switch settings before supplying power.
Switch changes made after supplying power will
take 15 to 20 seconds before becoming effective.

NOTE: Dual Input applications usually include one sensor with a smaller cell constant and one

sensor with a larger cell constant. Place the larger cell constant on Input 1.
This allows periodic recalibration of the larger cell by simply turning Input 2 OFF (OPEN).

2

3

1

CTS

4

3

2

3

1

CTS

CTS

ON

4

4

1

3

3

2

SW4

NOTE:

To work correctly with the 9900,
the 2850 must be set for the
custom cell constant or the actual
electrode cell constant and the
9900 set for a 1.0 cell constant.

SW3 or SW4

Custom Cell Constant

ON

1

0.01/cm

ON

1

0.1/cm

ON

1

1.0/cm

ON

1

10.0/cm

ON

1

20.0/cm

ON

1

Examples

CTS

Closed
Open

4

3

2

-1

CTS

Closed
Open

4

3

2

-1

CTS

Closed
Open

4

3

2

-1

CTS

Closed
Open

4

3

2

-1

CTS

Closed
Open

4

3

2

-1

CTS

Closed
Open

4

3

2

1.0 cell constant,

SW3 = Cell Constant and

Temperature Compensation

#1 #2 #3 #4 Cell Constant

C C C O Custom
C O O O 0.01 cm
O C O O 0.1 cm
C C O O 1.0 cm
O O C O 10.0 cm
C O C O 20.0 cm

-1

-1

-1

-1

-1

SW4 = Cell Constant and Input 2

#1 #2 #3 #4 Cell Constant

C C C O Custom
C O O O 0.01 cm
O C O O 0.1 cm
C C O O 1.0 cm
O O C O 10.0 cm
C O C O 20.0 cm

-1

-1

-1

-1

-1

temp comp Active

ON

1

CTS

4

3

2

1.0 cell constant,

temp comp Inactive

ON

CTS

Closed
Open

Closed

#4: (O) Open = Temp Comp ACTIVE
(C) Closed = Temp Comp INACTIVE

6

2850 Conductivity/Resistivity Sensor Electronics

#4: (O) Open = Input 2 INACTIVE
(C) Closed = Input 2 ACTIVE

Open

1

4

3

2

Range Selection for 4 to 20 mA Output

• The Range selection switch bank (SW2) provides eight range
selections for each cell constant.

• Each range can be inverted, making a total of 16 range options.

• Select a range from the table below and set SW2 as indicated.

Example (refer to shaded selections of chart):

• The electrode installed is the 3-2840-1V, with a 0.10 cell constant.

• The required output is 4 to 20 mA = 0 to 100 S.

• Set SW2 switch bank to C-C-O-O.

• To invert range (4 to 20 mA = 100 to 0 S), close switch #4.

CTS

ON

2

SW2

4

3

SW1

D3

1 3 2

CTS

ON

4

1

3

2

SW2

SW3

CTS

ON

4

1

3

2

1

SW2 Switch Setting 0.01 Cell

0.10 Cell

1.0 Cell 10.0 Cell 20.0 Cell

#1 #2 #3 #4 Resistivity Ranges in BOLD

CCCO10 to 20 MΩ 0 to 2 S 0 to 20 S 0 to 200 S 0 to 400 S

CCCC20 to 10 MΩ 2 to 0 S 20 to 0 S 200 to 0 S 400 to 0 S

OCCO 2 to 10 MΩ 0 to 5 S 0 to 50 S 0 to 500 S 0 to 1000 S

OCCC 10 to 2 MΩ 5 to 0 S 50 to 0 S 500 to 0 S 1 000 to 0 S

COCO 0 to 2 MΩ 0 to 10 S 0 to 100 S 0 to 1 000 S 0 to 2 000 S

COCC 2 to 0 MΩ 10 to 0 S 100 to 0 S 1 000 to 0 S 2 000 to 0 S

O O C O 0 to 1 S 0 to 50 S 0 to 500 S 0 to 5 000 S 0 to 10 000 S

O O C C 1 to 0 S 50 to 0 S 500 to 0 S 5 000 to 0 S 10 000 to 0 S

CCOO

0 to 5 S

0 to 100 S

0 to 1 000 S 0 to 10 000 S 0 to 20 000 S

C C O C 5 to 0 S 100 to 0 S 1 000 to 0 S 10 000 to 0 S 20 000 to 0 S

O C O O 0 to 10 S 0 to 200 S 0 to 2 000 S 0 to 50 000 S 0 to 100 000 S

OCOC 10 to 0 S 200 to 0 S 2 000 to 0 S 50 000 to 0 S 100 000 to 0 S

C O O O 0 to 50 S 0 to 500 S 0 to 5 000 S 0 to 100 000 S 0 to 200 000 S

C O O C 50 to 0 S 500 to 0 S 5 000 to 0 S 100 000 to 0 S 200 000 to 0 S

OOOO 0 to 100 S 0 to 1 000 S 0 to 10 000 S 0 to 200 000 S 0 to 400 000 S

O O O C 100 to 0 S 1000 to 0 S 10 000 to 0 S 200 000 to 0 S 400 000 to 0 S

Switch #4 inverts the loop output rangeNOTE:

(O) Open = 4 to 20 mA
(C) Closed = 20 to 4 mA

2850 Conductivity/Resistivity Sensor Electronics

7

Calibration

• All 2850 Conductivity/Resistivity Sensor Electronics are factory calibrated for maximum out-of-the-box accuracy.

• The EasyCal feature allows calibration to be performed at the sensor.

The 2839-2842 Conductivity sensors come with a certifi cate
of calibration. This certifi cate provides information regarding
the actual cell constant and temperature offset as tested and
verifi ed according to NIST standards. This information has
been programmed into the 2850 electronics as its default
factory value. If required, the sensor can be recertifi ed by
contacting the GF Signet repair department.

a. SW2: 4 to 20 mA output range selection switch bank
b. Power and Output terminal block: 4 to 20 mA or

Digital (S

3

L) Outputs

c. SW3 and SW4: Electrode Cell Constant selection

switch banks
d. D3: LED indicator
e. SW1: EasyCal Push-button
f. Input 1 & Input 2: Conductivity Electrode connections

a

b

c

3
2
1

SW2

CTS

ON

4
3
2

1

4

CTS

SW4

3

Input 2

2

ON

1

4

CTS

SW3

3
2

Input 1

ON

1

f

NOTE:

When the electrode is changed from its original factory
provided electrode or the application requires a cell constant

d

SW1

e

D3

change, reset SW3 or SW4 switches (see page 6).
Then perform a wet calibration with calibration standards.

EasyCal

EasyCal is a single-point calibration system. During this procedure, if the measured value is within ±10% of any of the test

values listed below, the 2850 will automatically recognize the test value and calibrate the output to that value.

NOTE: The fi rst step (Reset) is recommended each time an electrode is replaced, but is NOT necessary upon initial installation or

periodic calibration.

1. Reset the 2850 Sensor to factory calibration: Set all switches on SW3 (and SW4 for Dual Input) to OPEN. Apply power, wait

at least 3 seconds, then press and hold SW1 until the LED (D3) comes on steady then goes off again (approx. 10 seconds).

When the LED goes off, release SW1; reset is complete. Reset SW3 and SW4 to the proper settings.

2. Place the electrode/sensor assembly into the conductivity test solution appropriate to your operating range. Shake the

electrode to dislodge any air bubbles visible on the surface of the electrode.

• 146.93 S, 1408.8 S, 12856 S (per ASTM D1125-95)

• 10 S, 100 S, 200 S, 500 S, 1000 S, 5000 S, 10,000 S, 50,000 S, 100,000 S.

Allow at least 2 minutes for the electrode response to stabilize.

3. Press and hold SW1 for approximately 8 to 10 seconds. During this time, the LED will come on steady then go back off.

(If the LED blinks several times rapidly, the calibration was not successful. See the troubleshooting section).

Calibration is complete. Return the system to service.

Dual Input Calibration

Dual Input 3-2850-63 Electronics

• The 2850-63 can only be calibrated if both inputs are used, or if Input 2 is disabled.

• To disable Input 2: Set SW4, #4 to OPEN.

• Place each sensor into a test solution that represents the operating range of that sensor. When SW1 is pressed, the 2850 will

calibrate both inputs simultaneously.

• Dual Input applications usually include one sensor with a smaller cell constant and one sensor with a larger cell constant.

Place the larger cell constant on Input 1. This allows periodic recalibration of the larger cell by simply turning Input 2 OFF (OPEN).

8

2850 Conductivity/Resistivity Sensor Electronics

Maintenance

The 2850 requires no periodic maintenance.

• Coatings on the electrode may cause slow response or drift.

• Clean metallic surfaces with a mild detergent and a non-abrasive brush or cotton swab.

Troubleshooting

LED and Output Condition Possible Causes Suggested Solutions

Current Out:
LED off, current output is 22 mA

(S3L) out: "Check Sensor"

During EasyCal, the LED blinks
rapidly for 4 seconds.

After completing calibration
procedure, the output values are
inaccurate.

The output of the 2850 indicates a
value that is off by a factor of 10
(e.g. 10x, 100x the correct value)

• SW3 and SW4 set to all OPEN
(factory setting).

• No electrode installed.

• SW3 (and SW4) not set correctly.

• System not ready.

• Measured value of the test solution is
outside the ±10% tolerance.

• The electronics or the electrode is
defective.

• Insuffi cient time allowed for electrode
stabilization during calibration procedure.

• Test solutions are contaminated.

• EasyCal performed with temp comp
Inactive, then temp comp Active for
measurement. (or vice versa)

• The cell constant selection on the
2850 (SW3 or SW4) does not match
the actual input.

• Normal for new system.

• Install electrode.

• Set SW3 and SW4 correctly.

• Retry (recycle power).

• Use fresh test solutions and restart
the calibration.

• Replace the electronics or the
electrode.

• Recalibrate and wait at least 2
minutes after placing electrode in
solution before pressing SW1.

• Use fresh test solutions and restart
the calibration.

• Match the 2850 switch settings to
agree with the sensor being used.

2850 Conductivity/Resistivity Sensor Electronics

9

Electronic Certifi cation

Signet offers conductivity simulators in fi ve different values. These tools enable the user to validate the performance of the
electronics independently of the electrode. This requirement is defi ned by ASTM D 1125-95 (Standard Test Methods for Electrical
Conductivity and Resistivity of Water) which is commonly used for USP 24 applications.

Cond. - Resist.

Simulator

@ 25°C

For use with Signet

2850 Conductivity

NIST Traceable

3-2850.101-1 (159 001 392) 1.0 S ±0.1%

3-2850.101-2 (159 001 393) 2.5 S ±0.1%

3-2850.101-3 (159 001 394) 10.0 S ±0.1%

3-2850.101-4 (159 001 395) 18.2 M ±0.1%

3-2850.101-5 (159 001 396) 10.0 M ±0.1%

Before using the Simulator:

Before using the simulators, disconnect all electrodes and reset the 2850 Electronics to factory calibration:

1. Set all switches on SW3 (and SW4 for Dual Input) to OPEN. Turn the power on, wait at least 3 seconds

2. Press and hold SW1 until the LED (D3) comes on steady then goes off again (approx. 10 seconds).

3. When the LED goes off, release SW1. Reset is complete.

To validate Input 1:

1. Turn the power off.

2. Set SW3 to accept a 0.01 cell constant. Leave SW4 in the all-OPEN position.

3. Install the simulator into the 2850 at the Input 1 conductivity electrode terminals.

4. Connect the 2850 output terminals to the appropriate display instrument. Turn the power on.

• The display should indicate a conductivity value within ±2% of the simulator value.

• If the output is x10 or x100 of the correct value, recheck step 2. The 2850 is not set to accept a 0.01 cell constant.

• If the correct value is displayed, the electronics are calibrated to ASTM D 1125 specifi cations. Remove the simulator and
reset SW3 to the correct cell constant before reinstalling the electrode.

• If the correct value is not displayed, contact the factory.

To validate Input 2:

1. Turn the power off.

2. Set SW4 to accept a 0.01 cell constant.

3. Install the simulator into the 2850 at the Input 2 conductivity electrode terminals.

4. Set SW3 switches to the all-OPEN position.

5. Turn the power on and repeat step 4.

Remember to reset all switches to their correct position before resuming normal operation.

10

2850 Conductivity/Resistivity Sensor Electronics

Notes

2850 Conductivity/Resistivity Sensor Electronics

11

Ordering Information

Signet 2850 Conductivity/Resistivity Sensor Electronics

*All versions include EasyCal

Mfr. Part No. Code Description

3-2850-51 159 001 398 2850 Sensor Electronics with Digital (S

3

L) Output and ¾ inch adapter

3-2850-52 159 001 399 2850 Sensor Electronics with 4 to 20 mA Output and ¾ inch adapter

3-2850-61 159 001 400 2850 Sensor Electronics with Digital (S

3

L) Output and Universal adapter

3-2850-62 159 001 401 2850 Sensor Electronics with 4 to 20 mA Output and Universal adapter

3-2850-63 159 001 402 2850 Sensor Electronics with Dual Inputs, Dual Digital (S3L) Outputs and Universal adapter

(for use with 8900 only)

3

3-2850-51-39V 159 001 818 Integral 2850 system, Digital (S

L) output, 0.01 cell, PVDF NPT threads

3-2850-51-40V 159 001 819 Integral 2850 system, Digital (S3L) output, 0.1 cell, PVDF NPT threads

3-2850-51-41V 159 001 820 Integral 2850 system, Digital (S3L) output, 1.0 cell, PVDF NPT threads

3-2850-51-42V 159 001 821 Integral 2850 system, Digital (S3L) output, 10.0 cell, PVDF NPT threads

3-2850-51-39VD 159 001 822 Integral 2850 system, Digital (S

3

L) output, 0.01 cell, PVDF ISO threads

3-2850-51-40VD 159 001 823 Integral 2850 system, Digital (S3L) output, 0.1 cell, PVDF ISO threads

3-2850-51-41VD 159 001 824 Integral 2850 system, Digital (S3L) output, 1.0 cell, PVDF ISO threads

3-2850-51-42VD 159 001 825 Integral 2850 system, Digital (S3L) output, 10.0 cell, PVDF ISO threads

3-2850-52-39V 159 001 826 Integral 2850 system, 4 to 20 mA output, 0.01 cell, PVDF NPT threads

3-2850-52-40V 159 001 827 Integral 2850 system, 4 to 20 mA output, 0.1 cell, PVDF NPT threads

3-2850-52-41V 159 001 828 Integral 2850 system, 4 to 20 mA output, 1.0 cell, PVDF NPT threads

3-2850-52-42V 159 001 829 Integral 2850 system, 4 to 20 mA output, 10.0 cell, PVDF NPT threads

3-2850-52-39VD 159 001 830 Integral 2850 system, 4 to 20 mA output, 0.01 cell, PVDF ISO threads

3-2850-52-40VD 159 001 831 Integral 2850 system, 4 to 20 mA output, 0.1 cell, PVDF ISO threads

3-2850-52-41VD 159 001 832 Integral 2850 system, 4 to 20 mA output, 1.0 cell, PVDF ISO threads

3-2850-52-42VD 159 001 833 Integral 2850 system, 4 to 20 mA output, 10.0 cell, PVDF ISO threads

Parts and Accessories

3-9000.392-1 159 000 839 Liquid-tight connector kit, 1 set,

1

/2 in. NPT

3-9000.392-2 159 000 841 Liquid-tight connector kit, 1 set, PG 13.5

3-2850.101-1 159 001 392 Plug-in NIST-traceable recertifi cation tool, 1.0 S

3-2850.101-2 159 001 393 Plug-in NIST-traceable recertifi cation tool, 2.5 S

3-2850.101-3 159 001 394 Plug-in NIST-traceable recertifi cation tool, 10.0 S

3-2850.101-4 159 001 395 Plug-in NIST-traceable recertifi cation tool, 18.2 M

3-2850.101-5 159 001 396 Plug-in NIST-traceable recertifi cation tool, 10.0 M

Georg Fischer Signet LLC, 3401 Aero Jet Avenue, El Monte, CA 91731-2882 U.S.A. • Tel. [phone] • Fax [phone]
For Worldwide Sales and Service, visit our website: www.gfsignet.com • Or call (in the U.S.): [phone]
For the most up-to-date information, please refer to our website at www.gfsignet.com

3-2850.090-2 Rev. C 03/15 English © Georg Fischer Signet LLC 2015