Georg Fischer 2850 Specifications

Signet 2850 Conductivity/Resistivity Sensor
Electronics and Integral Systems with PVDF Sensor

Features

• Test certifi cate supplied with
all sensors

• Custom cell constant programmed into

Universal Mount

Junction Box

NPT Mount

Junction Box

2850 Integral Conductivity System
for in-line installations, PVDF

the electronics

• Integral mount systems for quick and
easy installation

• Compact design for maximum installation
fl exibility

• Extends the distance between the measuring
point and the 9900 Transmitter to
120 m (400 ft)

• Digital (S3L) interface or two-wire

4 to 20 mA output

The Signet 2850 Conductivity/Resistivity Sensor
Electronics are available in various confi gurations
for maximum installation fl exibility. The universal
mount version is for pipe, wall, or tank mounting and
enables single or dual (digital versions only) inputs
using any standard Signet conductivity/resistivity
sensor. The threaded j-box version can be used with
these same Signet sensors for submersible sensor
mounting. It is also available as a combined integral
system confi guration for in-line mounting and includes
a conductivity electrode in a choice of 0.01, 0.1, 1.0,

10.0 or 20.0 cm
applications with a conductivity range of 0.055 to

400,000 S or a resistivity range of 18.2 M to 10 k.

All 2850 units are available with a digital (S
a single 4 to 20 mA. The digital (S
be paired with the 9900 or 9950 Transmitter to extend the
distance between the measuring points to 120 m (400 ft).

The 8900 Multi-Parameter Controller allows for up to six
2850 (S
the Signet 8900 Multi-Parameter Controller. All 2850
units are built with NEMA 4X/IP65 enclosures which allow
output wiring connections with long cable runs of up to
305 m (1,000 ft).

3

L) output conductivity sensors to be used with

-1

cell constants. The 2850 is ideal for

3

3

L) output version can

L) output, or

• EasyCal with automatic test solution
recognition

• For use with ALL Signet conductivity
electrodes

Applications

• Water Treatment & Water Quality Monitoring

• Reverse Osmosis

• Deionization

• Demineralizer, Regeneration & Rinse

• Scrubber, Cooling Tower and Boiler Protection

• Aquatic Animal Life Support Systems

The two-wire 4 to 20 mA output version is available with
eight 4 to 20 mA output ranges for each electrode cell
constant. Each range can be inverted and is
fi eld selectable.

EasyCal is a standard feature that automatically
recognizes conductivity test solution values for simple
fi eld calibration. A certifi cation tool is available for
validation of the sensor electronics according to
USP requirements.

U.S. Patent No.: 7,550,979 B2

Specifi cations

General

Compatible Electrodes All Signet Sensors

Materials

NPT Mount Junction Box for Integral Mount PBT
Universal/Remote Mount PBT, CPVC
EasyCal - Automatic Recognition of the Following Conductivity Values

146.93 µS, 1408.8 µS, 12856 µS (@25 °C) (Test solutions Per ASTM D1125-95)
10 µS, 100 µS, 200 µS, 500 µS, 1000 µS, 5000 µS, 10,000 µS, 50,000 µS, 100,000 µS
(@ 25 °C) (Standard test solutions)

Electrical

Power 12 to 24 VDC ±10%, regulated for 4 to 20 mA output (typically called “Loop Powered”)

5 to 6.5 VDC ±5% regulated recommended (provided by the Signet 8900, 9900, 0486),

Digital (S

3

L) Output: Serial ASCII, TTL level 9600 bps

Accuracy Conductivity ± 2% of reading

Resolution Conductivity 0.1% of reading

Update Rate Conductivity and

3

Available Data via Digital (S

L) Output

Max. Temperature/Pressure Rating

Operating Temperature -10 °C to 85 ° C 14 °F to 185 °F

Storage Temperature -20 °C to 85 ° C -4 °F to 185 °F
Relative Humidity 0 to 95%, non-condensing
Enclosure NEMA 4X/IP65
Current Output

Field-selectable ranges
Factory Set Span
(Integral mount only)

*Special Order
**Test certifi cate supplied with all sensors. Custom cell constant programmed into the electronics.
Max. Loop Resistance 50 Ω @ 12 VDC

Accuracy ± 2% of output span
Resolution 7 µA
Update Rate < 600 ms
Error Indication 22 mA
Pure Water Compensation When using 0.01-cm cell and raw conductivity value < 0.5 µS, the 2850 auto-switches to

Shipping Weight

Standards and Approvals

3.0 mA max for Digital (S3L) output (Reverse polarity and short circuit protected)

Temperature < 0.2 °C

Temperature < 0.2 °C

< 600 ms

Temperature

Raw conductivity
Calibrated conductivity
Calibrated temperature-compensated conductivity
Temperature

0.01 cell (2839**) 4 to 20 mA = 0 to 100 µS

0.10 cell (2840**) 4 to 20 mA = 0 to 1000 µS

1.0 cell (2841**) 4 to 20 mA = 0 to 10,000 µS

10.0 cell (2842**) 4 to 20 mA = 0 to 200,000 µS

20.0 cell (2823)* 4 to 20 mA = 0 to 400,000 µS

325 Ω @ 18 VDC
600 Ω @ 24 VDC

compensate for non-linear temperature e ects found in this low conductivity
(high resistivity) range.

NPT Mount

0.75 kg 1.75 lb
Junction Box
Universal Mount 0.75 kg 1.75 lb

CE, FCC
RoHS compliant, China RoHS
Manufactured under ISO 9001 for Quality and ISO 14001 for Environmental

Management and OHSAS 18001 for Occupational Health and Safety

www.gfsignet.com