Georg Fischer 8850 Operating Manual

Signet 8850-1 Conductivity/Resistivity Transmitter

*3-8850.090-1*

3-8850.090-1 Rev. G 3/06 English

English

CAUTION!

• Remove power to unit before wiring
input and output connections.

• Follow instructions carefully to avoid
personal injury.

Contents

1. Installation

2. Specifi cations

3. Electrical Connections

4. Menu Functions

62.50 uS/cm

Conductivity/Resistivity

1. Installation

ProcessPro transmitters are available in two styles: panel mount and fi eld mount. The panel mount is supplied with the necessary
hardware to install the transmitter. This manual includes complete panel mounting instructions.
Field mounting requires a separate mounting kit. The 3-8050 Universal kit enables the transmitter to be installed virtually
anywhere. Detailed instructions for fi eld installation options are included with the 3-8050 Universal kit.

1.1 Panel Installation

1. The panel mount transmitter is designed for installation using a 1/4 DIN Punch. For manual panel cutout, an adhesive
template is provided as an installation guide. Recommended clearance on all sides between instruments is 1 inch.

2. Place gasket on instrument, and install in panel.

3. Slide mounting bracket over back of instrument until quick-clips snap into latches on side of instrument.

4. To remove, secure instrument temporarily with tape from front or grip from rear of instrument. DO NOT RELEASE.

Press quick-clips outward and remove.

96 mm

(3.8 in.)

FRONT VIEW

Field Mount &

Panel Mount

96 mm
(3.8 in.)

41 mm
(1.6 in.

)

SIDE VIEW

Panel Mount

Optional
Rear
Cover

56 mm
(2.2 in.)

97 mm
(3.8 in.)

92 mm
(3.6 in.)

8050

42 mm
(1.7 in.)

64 mm
(2.5 in.)

106 mm (4.2 in.)

SIDE VIEW

Field Mount w/
8050 Universal base

82 mm
(3.23 in.)

42 mm
(1.7 in.)

107 mm (4.2 in.)

SIDE VIEW

Field Mount w/
8052 Integral kit

8052

65 mm
(2.5 in.)

96 mm

(3.8 in.)

25.0 C

Signet

Transmitter

ENTER

2. Specifi cations

General

Compatible electrodes: Signet 3-28XX-1 Standard and Certifi ed

Series Conductivity/Resistivity Electrodes
Accuracy: ±2% of reading
Enclosure:

• Rating: NEMA 4X/IP65 front

• Case: PBT

• Panel case gasket: Neoprene

• Window: Polyurethane coated polycarbonate

• Keypad: Sealed 4-key silicone rubber

• Weight: Approx. 325g (12 oz.)
Display:

• Alphanumeric 2 x 16 LCD

• Contrast: User selected, 5 levels

• Update rate: 1.8 s

Electrical

• Power: 12 to 24 VDC ±10%, regulated, 80 mA max.
Sensor input range:

• Conductivity: 0.01 µS/cm to 400,000 µS/cm

• Resistivity: 10 KΩ•cm to 100 MΩ•cm

• TDS: 0.023 to 200 000 PPM nominal (adjustable µS/PPM)

• Temperature: PT 1000, -25 to 120°C (-13 to 248°F)
Measurements above 10 MΩ (below 0.1 µS) must be

performed in solution temperatures from 20°C to 100°C.

4 to 20 mA Outputs:

• Passive, isolated, fully adjustable and reversible 4 to 20 mA

outputs are independently source selectable for conductivity
or temperature.

• Max loop impedance: 50 Ω max. @ 12 V
325 Ω max. @ 18 V
600 Ω max. @ 24 V

• Update rate: 200 ms

• Accuracy: ±0.03 mA @ 25°C, 24 V
Open-collector output, optically isolated:

• 50 mA max. sink, 30 VDC maximum pull-up voltage.

• Programmable for:

• High, Low with adjustable hysteresis

• Pulse operation (max. rate: 400 pulses/min).

Environmental

• Operating temperature: -10 to 70°C (14 to 158°F)

• Storage temperature: -15 to 80°C (5 to 176°F)

• Relative humidity: 0 to 95%, non-condensing

• Maximum altitude: 2000 m (6562 ft)

• Insulation category: II

• Pollution degree: 2

Standards and Approvals

• CE, UL listed

• Immunity: EN50082-2

• Emissions: EN55011, Class B

• Manufactured under ISO 9001 and ISO 14001

U.S.A. Patent # 5,708,363

3. Electrical Connections

Caution: Failure to fully open terminal jaws before removing wire may permanently damage instrument.

Wiring Procedure

1. Remove 0.5 - 0.625 in. (13-16 mm) of insulation from wire end.

2. Press the orange terminal lever downward with a small screwdriver to open terminal jaws.

3. Insert exposed (non-insulated) wire end in terminal hole until it bottoms out.

4. Release orange terminal lever to secure wire in place. Gently pull on each wire to ensure a good connection.

Wiring Removal Procedure

1. Press the orange terminal lever downward with a small screwdriver to open terminal jaws.

2. When fully open, remove wire from terminal.

Wiring Tips:

• Do not route sensor cable in conduit containing AC power wiring. Electrical noise may interfere with sensor signal.

• Routing sensor cable in grounded metal conduit will help prevent electrical noise and mechanical damage.

• Seal cable entry points to prevent moisture damage.

• Only one wire should be inserted into a terminal. Splice double wires outside the terminal.

2

1

Terminals 3 and 4: Loop Power

12-24 VDC ±10% system power

and current loop output.

Max. loop impedance:

50 Ω max. @ 12 V
325 Ω max. @ 18 V
600 Ω max. @ 24 V

System Pwr

4

Loop -

System Pwr

3

Loop +

AUX

2

Power -

AUX
Power +

1

Terminals 1-2: Auxiliary power

Provides DC power to measurement circuit.
Required for all 8850 systems

6

5

Output -

Output +

Internal open-collector

output circuit

S

Terminals 7-10: Sensor input

7 is conductivity input
8 is temperature input
9 is the isolated signal ground
10 is the sensor earth ground

9

8

7

Sensr Gnd
(SHIELD)

Iso. Gnd
(BLACK)

Temp. IN
(WHITE)

Signal IN
(RED)

10

15Ω

Output --

Output +

≤ 100 ft. (30 m)

3.1 Sensor Input Connections

Terminals

Shield (Sensor Gnd)

10

Black (Iso Gnd)

9

White (Temp In)

8

Red (Signal In)

7

Isolation

Terminals 5-6: Open-collector Output

• A transistor output, programmable (see CALIBRATE menu)
as High or Low setpoint with adjustable hysteresis and
proportional Pulse (to 400 pulses per minute maximum).

• May be disabled (Off) if not used.

D

62.50 uS/cm

25.0 C

Signet

Conductivity/Resistivity

Transmitter

ENTER

Signet 28XX-1

Standard and Certified Cells

2 8850-1 Conductivity/Resistivity Transmitter

Select the sensor with the range that best straddles your
application requirements.

• 2819-1, 2839-1 (0.01 cell): 0.01 to 100 µS
(10 kΩ to 100 MΩ)
Use the 2819-1 or the 2839-1 for all resistivity requirements

• 2820-1, 2840-1 (0.1 cell): 1 to 1000 µS

• 2821-1, 2841-1 (1.0 cell): 10 to 10,000 µS

• 2822-1, 2842-1 (10.0 cell): 100 to 200,000 µS

• 2823-1 (20.0 cell): 200 to 400,000 µS

UPW @ 25°C

3-2819, 3-2839

Bottled

USP

Rinse
Water

3-2820, 3-2840 ( 0.10 Cell)

Water

3-2822, 3-2842 (10.0 Cell)

3-2821, 3-2841 (1.0 Cell)

(0.01 Cell)

3-2823

Cooling Tower
Waste Waters

Brackish Sea Water

(Salinity)

Deionization Regen. Chemicals

Alkali Cleaners, Acids/Bases

(20.0 Cell)

3.2 System Power/Loop Connections

Stand-alone application, no current loop used

System Pwr Loop -

System Pwr Loop +

AUX Power -

AUX Power +

Connection to a PLC/Recorder, separate supply

Transmitter

Terminals

System Pwr Loop -

System Pwr Loop +

AUX Power -

AUX Power +

AUX power required for all 8850 systems

4

4

3

3

2

2

1

1

Transmitter

Terminals

PLC or Recorder

+

Loop Input

4-20 mA

-

Power

-

Supply

+

12-24 VDC

0.010mS
100 MΩ

4

4

3

3

2

2

1

1

0.054mS

18.3 MΩ

1mS
1MΩ

­+

10mS

100KΩ

Power

Supply

12-24 VDC

100mS

10KΩ

1,000mS 10,000mS

200mS

50,000mS

100,000mS

200,000mS

400,000mS

Connection to a PLC with built-in power supply

System Pwr Loop -

System Pwr Loop +

AUX Power -

AUX Power +

Transmitter

Terminals

4

4

3

3

2

2

1

1

Internal

Connection

PLC

PLC Terminals

Loop Input

+

4-20 mA

-

Power

-

Supply

+

12-24 VDC

Example: Two transmitters connected to PLC/Recorder with separate power supply

PLC or Recorder

+

Channel 1
4-20 mA in

-

­+

­+

Channel 2
4-20 mA in

Power

Supply

12-24 VDC

Transmitter 2

System Pwr Loop -

System Pwr Loop +

AUX Power -

AUX Power +

Transmitter 1

Terminals

4

3

2

1

Terminals

System Pwr Loop -

4

4

System Pwr Loop +

3

3

AUX Power -

2

2

AUX Power +

1

1

38850-1 Conductivity/Resistivity Transmitter

3.3 Open Collector Output

The Open Collector output can be used as a switch that responds
when the process value moves above or below a setpoint, or
it can be used to generate a pulse at a rate proportional to the
process value.

• Low:
Output triggers when process variable is less than the setpoint.
The output will relax when the process variable moves above the
setpoint plus the hysteresis value.

• High:
Output triggers when process variable is greater than the
setpoint. The output will relax when the process variable moves
below the setpoint plus the hysteresis value.

Process

Hysteresis

Low Setpoint

Time

Relay energized

Relay relaxed

• Proportional Pulsing
The Open Collector output will generate a 100 mS pulse at the
rate defi ned by settings in the CALIBRATE menu.

In the example below:

• The output will be 0 pulses/min. when value is less than 5.

• The output will be 50 pulses/min. when value is 7.5.

• The output will be 100 when value is greater than 10.

The starting point, endpoint and maximum pulse rate are select ­able in the CALIBRATE menu.

100 pulses

0 to 100 Pulses/min.

Open Collector Output Rate:

Pulse rate

0 pulses

Process

5

Starting point

High Setpoint

Hysteresis

Time

VIEW menu

• During normal operation, ProcessPro displays the VIEW menu.

• When editing the CALIBRATE or OPTIONS menus, ProcessPro will return to the VIEW menu if no activity
occurs for 10 minutes.

• To select a VIEW display, press the UP or DOWN arrow keys. The selections will scroll in a continuous
loop.

• Changing the VIEW display does not interrupt system operations.

• No key code is necessary to change display selection.

• Output settings cannot be edited from the VIEW menu.

View Menu

Display Description

10

endpoint

62.50 uS/cm

Conductivity/Resistivity

Transmitter

25.0 C

Signet

ENTER

123.45 µS/cm
+67.89 ºC

Monitor the Conductivity and Temperature values from the sensor.
This is the permanent display.

The VIEW displays below are temporary. The permanent display will return after 10 minutes

Loop Output:

13.75 mA

Last CAL:
04-20-07

4 8850-1 Conductivity/Resistivity Transmitter

Monitor the Loop Current output.

Check the Last Calibration date.

ProcessPro Editing Procedure:

Step 1. Press and hold ENTER key:

• 2 seconds to select the CALIBRATE menu.

• 5 seconds to select the OPTIONS menu.

Step 2. The Key Code is UP-UP-UP-DOWN keys in sequence.

• After entering the Key Code, the display will show the fi rst item in the selected menu.

Step 3. Scroll menu with UP or DOWN arrow keys.
Step 4. Press RIGHT ARROW key to select menu item to be edited.

• The fi rst display element will begin fl ashing.

Step 5. Press UP or DOWN keys to edit the fl ashing element.

• RIGHT ARROW key advances the fl ashing element.

Step 6. Press ENTER key to save the new setting and return to Step 3.

Notes on Step 1:

• The View Menu is normally displayed.

• The CALIBRATE and OPTIONS menus require a KEY CODE.

Press &
hold for
access:

VIEW

ENTER

Notes on Step 2:

If no key is pressed for 5 minutes while display is showing "Enter
Key Code", the display will return to the VIEW menu.

2s 5s

CALIBRATE

OPTIONS

Notes on Steps 3 and 4:

• Refer to pages 6 and 7 for complete listing of menu items and their use.

• From the Step 3 display, pressing the UP and DOWN keys simultaneously will
return the display to the VIEW menu.

• If no key is pressed for 10 minutes, display will also return to the VIEW menu.

Step 3: Finished Editing?

Press the UP and DOWN keys simultaneously after
saving the last setting to return to normal operation.

CALIBRATE: ----

Enter Key Code

CALIBRATE: *---

Enter Key Code

CALIBRATE: **--

Enter Key Code

CALIBRATE: ***-

Enter Key Code

Cell Constant:

Standard >

Cell Constant:

Output Setpnt:

20.0 uS >

First item in CALI­BRATE menu

Standard >

Step 3

Step 4

Notes on Steps 5 and 6:

• All output functions remain active during editing.

• Only the fl ashing element can be edited.

• RIGHT ARROW key advances the fl ashing element in a continuous loop.

• Edited value is effective immediately after pressing ENTER key.

• If no key is pressed for 10 minutes unit will restore the last saved value and return to step 3.

• Step 6 (pressing ENTER key) always returns you to Step 3.

• Repeat steps 3-6 until all editing is completed.

Output Setpnt:

Step 5: Made an Error?

Press the UP and DOWN keys simultaneously
while any element is fl ashing. This will recall the
last saved value of the item being edited and
return you to Step 3.

20.00 uS

Output Setpnt:

10.00 uS

Output Setpnt:

1

Step 6

Output Setpnt:

19.00 uS >

0

.00 uS

Output Setpnt:

Step 5

9

1

.00 uS

Output Setpnt:

Saving

ENTER

58850-1 Conductivity/Resistivity Transmitter

Calibrate Menu

Display

(Factory settings shown)

Description

Cell Constant:

Standard >

Cell: Standard

1 >

Cell: Custom

1.0000 >

Cond Units:

uS >

PPM Factor:

2.00 >

Set:

Temperature >

Set:

Conductivity >

Select CUSTOM only if you are connecting a certifi ed conductivity sensor. Select STANDARD
for all other systems.

For STANDARD sensors: Select from these options: 0.01, 0.1, 1.0, 10.0 or 20.0.

For CUSTOM sensors: Enter the precise cell constant from the certifi cate provided with your
sensor, or from the information label on the sensor.

Select from the following options: µS, mS, kΩ, MΩ, PPM

If the Units selection is PPM, you can set the ratio of Total Dissolved Solids to µS. See
section 3 of this manual for additional information. The TDS factor can only be set in PPM.

Adjust the temperature of the system based on an accurate external reference.

For use with STANDARD sensors: Perform this single-point wet calibration for most accurate
results. Not required for CUSTOM sensors except for periodic system accuracy confi rmation.
Enter all zeroes to restore factory calibration to TEMP and COND settings.

Loop Source:

Cond >

Loop Range: uS

0.0000 → 100.000 >

Output Source:

Cond >

Output Mode:

Low >

Output Setpnt:

10.0000 uS >

Output Hys:

0.5000 uS >

Output Rng: uS

10.0000 → 40.0000 >

Select the input source to be associated with the current loop output: Conductivity or
Temperature.

Select the minimum and maximum values for the current loop output.
Be sure to modify this setting if you change the Cond. Units.

Select the source for the Open Collector output: Conductivity or Temperature

Select the mode of operation for the Open Collector output.
Options available are High, Low or proportional Pulse.
The signal may be disabled (Off) if not in use.

In Low or High Mode, this Open Collector output will be activated when the process reaches
this value. Be sure to modify this setting if you change the Cond. Units.

The Open Collector output will be deactivated at Setpoint ± Hysteresis, depending on High or
Low Setpoint selection. (See details on page 4.)

In Pulse mode, set the process values where the proportional pulse will start and where it will
reach the maximum rate. Be sure to modify this setting if you change the Cond. Units.

Output PlsRate:

120 Pulses/Min >

Last CAL:

In Pulse mode, set the maximum rate for the proportional Pulse output. The 8850 will accept
any value from 0 to 400.

Use this “note pad” to record important dates, such as annual recertifi cation or scheduled
maintenance.

04-20-07 >

6 8850-1 Conductivity/Resistivity Transmitter

Options Menu

Display

(Factory settings shown)

Contrast:
3 >

Cond Decimal:
****.* >

Averaging

Adjust the LCD contrast for best viewing. A setting of 1 is lower contrast, 5 is higher. In
general, select lower contrast if the display is in warmer ambient surroundings.

Set the decimal to the best resolution for your application. The display will auto matically
scale down to this restriction. Select *****., ****.*, ***.** **.*** or *.****

OFF provides the most instantaneous response to process changes. Select LOW (4 sec)
or HIGH (8 sec) averaging if your process experiences frequent or extreme fl uctuations.

Off >

Loop Adjust:

4.00 mA >

Loop Adjust:

Adjust the minimum and maximum current output. The display value represents the
precise current output. Adjustment limits:

• 3.80 mA < 4.00 mA > 5.00 mA

• 19.00 mA < 20.00 mA > 21.00 mA
Use this setting to match the system output to any external device.

20.00 mA >

Temp Display:

Select ºC or ºF

ºC >

Temperature

Set the percent change in Conductivity caused by a 1ºC change in temperature. May be
from 0.00 to 10.00.

Comp %: 2.00 >

Description

Output Active:

Low >

Test Loop:
>

Test Output:

Active HIGH: This setting is used to turn a device (pump, valve) ON at the setpoint.

Active LOW: This setting is used to turn a device OFF at the setpoint.

Press UP and DOWN keys to manually order any output current value from 3.6 mA to

21.00 mA to test the output loop.

Press UP and DOWN keys to manually toggle the Open Collector output state.

>

78850-1 Conductivity/Resistivity Transmitter

Calibration Procedure

r

This instrument has been electronically calibrated at the factory.

• Procedure A verifi es the accuracy and linearity of the instrument by simulating temperature and conductivity values with precision
(±0.1%) fi xed resistors.

• Procedure B is a wet calibration. This procedure uses the sensor input and NIST traceable test solutions. When done correctly, this
procedure offers the most accurate system calibration.

A) Accuracy Verifi cation with Precision Resistors (Electronic Calibration):

1. Simulate the Temperature

The temperature input to the 8850 is a PT-1000 thermistor, where 1000 Ohms (Ω) is equal to 0ºC and a change of 3.84 Ω equals a

1ºC change. (1000 Ω = 0ºC, 1003.84 Ω = 1.0ºC, 1007.68 Ω = 2.0 ºC...................1096 Ω = 25ºC)

• Connect a resistor (1000 Ω to 1096 Ω ) between "Temp IN" and "Iso. Gnd" terminals.

• Set Temp; Adjust the temperature to exact value based on the measured resistance. (see Editing Procedure, Calibrate menu).

• To verify the temperature linearity, connect a second resistor value to the terminals.

• If the instrument does not display the correct value, service is required. ( ± 0.5ºC)

2. Simulate the Conductivity

You may calculate the exact Resistance needed to simulate a specifi c conductivity value, or you may calculate the exact Conductivity
based on a resistor value:

Resistance = Cell constant e.g. 0.1 Cell = 5,000 Ω or 5 KΩ
conductivity (Siemens*) 0.000020 (Siemens*)

Conductivity = Sensor cell e.g. 0.1 Cell = 0.000001 Siemens*
Simulation resistance (Ω) 100,000 (Ω) or 1µS/cm

(*1 µS = 1 X 10

• Connect the conductivity resistor between the "Signal IN " and "Iso Gnd" terminals.

• Set Cond: Adjust the conductivity value based on the resistor value. (see Editing
Procedure and Calibrate menu).

• Verify the linearity of the instrument by connecting a second resistor of a different value.

• If the instrument does not display the correct value (± 2% of reading), service is required.

-6

Siemens or 0.000001 Siemens)

9

8

7

Iso. Gnd
(BLACK)

Temp. IN
(WHITE)

Signal IN
(RED)

TC resistor

Simulation resisto

B) Wet Calibration with NIST Traceable Solutions:

When using NIST traceable standards, review the temperature information provided with the test solution. Prevent contamination of the
test solution. The sensor must be at the temperature specifi ed on the test solution label.

• Remove the sensor from the system. Rinse the sensor in a small amount of test solution.

• Place the sensor into the test solution.

• Place a reference thermometer into the same solution.

• Allow suffi cient time for the temperature to stabilize.

• Set Temp: Adjust the temperature value based on the reference thermometer. (see Editing Procedure.)

• Set Cond: Adjust the conductivity value based on the test solution value. (see Editing Procedure.)

• Verify the linearity by placing the sensor into a second test solution of a different value.

• If the instrument does not display the correct value (Temperature ± 0.5ºC, Conductivity ± 2% of reading), service is required.

8 8850-1 Conductivity/Resistivity Transmitter

Temperature Coeffi cient

Conductivity measurement is highly dependent on temperature. Temperature dependence is expressed as the relative change per °C,
commonly known as percent/°C change from 25°C, or slope of the solution.

Slopes can vary signifi cantly depending on process solution type. The factory default temperature compensation factor is 2.00%/°C.
Process solutions may require adjustment for maximum accuracy. To determine the optimum temperature compensation factor for a
process:

1. Disable the 8850 temperature compensation % factor by entering 0.00.

2. Heat the sample solution close to the maximum process temperature. Place sensor in the sample solution allowing several

minutes for stabilization. Access the VIEW menu and record the displayed temperature and conductivity values in the spaces
provided:

Displayed temperature: T1 = _______ °C
Displayed conductivity: C1 = _______ µS

(Do not use this procedure for solutions from 0.055 µS to 0.1 µS (10 MΩ to 18 MΩ). An internal pure water curve is used for these
ranges. The factory default setting of 2.00%/°C should be used.)

3. Cool the sample solution close to the minimum process temperature. Place sensor in the sample solution allowing several
minutes for stabilization. Record displayed temperature and conductivity values in the spaces provided:

Displayed temperature: T2 = _______ °C
Displayed conductivity: C2 = _______ µS

(A 10% change in conductivity between steps 2 and 3 is recommended.)

4. Substitute recorded readings (steps 2 and 3) into the following formula:

TC Slope = 100 x (C1 - C2)
(C2 x (T1 - 25)) - (C1 x (T2 - 25))

Example: A sample solution has a conductivity of 205 µS @ 48°C. After cooling the solution, the conductivity was measured at

150 µS @ 23°C. (C1 = 205, T1 = 48, C2 = 150, T2 = 23)

The TC is calculated as follows:

TC Slope = 100 x (205 - 150) = 5500 = 1.42%/°C
(150 x (48 - 25)) - (205 x (23 - 25)) 3860

Parts Per Million (PPM) Factor

This feature is only applicable when PPM display units are selected. The programmable PPM Factor is adjustable from 0.01 to

3.00 (factory default = 2.00).

Determine the best PPM Factor for a process solution by calculating the solution's conductivity (µS) and the percent of total
dissolved solids (PPM).

PPM Factor = Solution conductivity (µS/cm)
Total dissolved solids (PPM)

TDS (PPM) = Solution conductivity (µS/cm)
PPM Factor

Example: • Solution conductivity = 400 µS/cm

• TDS = 200 PPM (mg/L)

200 PPM

PPM Factor = 400 µS/cm = 2.00

98850-1 Conductivity/Resistivity Transmitter

Troubleshooting

Display Condition Suggested SolutionsPossible Causes

"- - - -"

Value Must be less
than 3

Value must be greater than 0

"Value must be
400 or less"

Display erratic, shows "0" or
"------" intermittently

"Too much Error
Check Sensor"

• Display is over range. This may be
a normal condition if your process
operates at/near the limits of the sensor
range.

The PPM factor must be a value from

0.00 to 3.00

Custom cell constant cannot be set to 0

Pulse Rate cannot be greater than 400

Aux Power not connected

• Defective or dirty/coated sensor

• Wiring error

• Fluid conductivity too low

• Defective temp element

• Check sensor for correct range.

• Check Decimal setting in OPTIONS menu.

• Check Calibrate menu settings for incompatible
SOURCE and RANGE values.

Set a PPM value less than 3.

Set cell constant to a value greater than 0

Set a pulse rate value less than 400

Wire 8850 according to diagram (Section 3.1)

• Clean or replace sensor

• Check and correct wiring

• Replace sensor

Technical notes

If a Current Loop is locked at 3.6 mA, the problem is related to the temperature circuit:
This occurs only if the 8850 detects a resistance from the temperature sensor that is less than 250Ω or greater than 2800Ω.

• Check the sensor wiring for open/short or poor connections on white (TEMP IN) and black (ISO GND)wires.

• The PT1000 temperature device in the sensor is defective.

• The transmitter is defective.

Auxiliary Power (terminals 1 and 2) must ALWAYS be connected for the 8850 to operate.

10 8850-1 Conductivity/Resistivity Transmitter

Notes

118850-1 Conductivity/Resistivity Transmitter

Ordering Information

Mfr. Part No Code Description

3-8850-1 159 000 228 Conductivity/Resistivity transmitter Field mount
3-8850-1P 159 000 229 Conductivity/Resistivity transmitter Panel mount

Parts and Accessories

Mfr. Part No Code Description

3-8050 159 000 184 Universal mounting kit
3-8050.395 159 000 186 Splashproof rear cover
3-8052 159 000 188 3/4” Integral mounting kit
3-8052-1 159 000 755 3/4" NPT mount junction box
3-0000.596 159 000 641 Heavy duty wall mount bracket
3-8050.392 159 000 640 Model 200 retrofi t adapter
3-5000.598 198 840 225 Surface mount bracket
3-5000.399 198 840 224 5 x 5 inch adapter plate for Signet retrofi t
3-9000.392 159 000 368 Liquid-tight connector kit, 3 sets, 1/2 in. NPT
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
7300-7524 159 000 687 24 VDC Power Supply 7.5 W, 300mA
7300-1524 159 000 688 24 VDC Power Supply 15 W, 600mA
7300-3024 159 000 689 24 VDC Power Supply 30 W, 1.3 A
7300-5024 159 000 690 24 VDC Power Supply 50 W, 2.1 A
7300-1024 159 000 691 24 VDC Power Supply 100 W, 4.2 A

Conductivity/Resistivity Electrodes

Mfr. Part No. Code Description

3-2819-1 198 844 010 Conductivity/Resistivity (CR) Cell, 0.01, SS
3-2820-1 198 844 000 Conductivity Cell, 0.1, SS
3-2821-1 198 844 001 Conductivity Cell, 1.0, SS
3-2822-1 198 844 002 Conductivity Cell, 10, SS
3-2823-1 198 844 003 Conductivity Cell, 20, SS
3-2819-S1 159 000 085 CR Sanitary, 0.01, SS, 1 to 1 1/2 in.
3-2819-S1C 159 000 087 CR Sanitary, 0.01, SS, 1 to 1 1/2 in., Certifi ed
3-2819-S2 159 000 086 CR Sanitary, 0.01, SS, 2 in.
3-2819-S2C 159 000 088 CR Sanitary, 0.01, SS, 2 in., Certifi ed
3-2819-T1 159 000 081 CR Sanitary, 0.01, Titanium, 1 to 1 1/2 in.
3-2819-T1C 159 000 083 CR Sanitary, 0.01, Titanium, 1 to 1 1/2 in., Certifi ed
3-2819-T2 159 000 082 CR Sanitary, 0.01, Titanium, 2 in.
3-2819-T2C 159 000 084 CR Sanitary, 0.01, Titanium, 2 in., Certifi ed
3-2820-S1 159 000 089 CR Sanitary, 0.1, SS, 1 to 1 1/2 in.
3-2820-S1C 159 000 091 CR Sanitary, 0.1, SS, 1 to 1 1/2 in., Certifi ed
3-2820-S2 159 000 090 CR Sanitary, 0.1, SS, 2 in.
3-2820-S2C 159 000 092 CR Sanitary, 0.1, SS, 2 in., Certifi ed
3-2820-T1 159 000 624 CR Sanitary, 0.1, Titanium, 1 to 1 1/2 in.
3-2820-T2 159 000 625 CR Sanitary, 0.1, Titanium, 2 in.
3-2821-S1 159 000 093 CR Sanitary, 1.0, SS, 1 to 1 1/2 in.
3-2821-S1C 159 000 095 CR Sanitary, 1.0, SS, 1 to 1 1/2 in., Certifi ed
3-2821-S2 159 000 094 CR Sanitary, 1.0, SS, 2 in.
3-2821-S2C 159 000 096 CR Sanitary, 1.0, SS, 2 in., Certifi ed
3-2821-T1 159 000 626 CR Sanitary, 1.0, Titanium, 1 to 1 1/2 in.
3-2821-T2 159 000 627 CR Sanitary, 1.0, Titanium, 2 in.
3-2839-1 159 000 921 Conductivity Cell, 0.01, 15 ft cable, NPT
3-2839-1D 159 000 923 Conductivity Cell, 0.01, 15 ft cable, ISO
3-2840-1 159 000 786 Conductivity Cell, 0.1, 15 ft cable, NPT
3-2840-1D 159 000 788 Conductivity Cell, 0.1, 15 ft cable, ISO
3-2841-1 159 000 790 Conductivity Cell, 1.0, 15 ft cable, NPT
3-2841-1D 159 000 792 Conductivity Cell, 1.0, 15 ft cable, ISO
3-2842-1 159 000 794 Conductivity Cell, 10.0, 15 ft cable, NPT
3-2842-1D 159 000796 Conductivity Cell, 10.0, 15 ft cable, ISO

NOTE: Alternate wetted materials and lengths are available through special order.
Cable length extensions to 100 ft. (30 m) are available through special order.

George Fischer Signet, Inc., 3401 Aerojet 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]

3-8850.090-1 Rev. G 3/06 English © George Fischer Signet, Inc. 1999 Printed in U.S.A. on Recycled Paper