C800 Electrochemical Converter

Single and Dual Channel Converter for Electrochemical Sensors

The Control 800 series of electrochemical converters combines high performance digital conductivity and analog pH measurements with intuitive operation. It has been designed for easy integration into skids and panels to cover a wide range of bioprocess applications in both, conventional stainless steel and single-use systems.

  • Designed for Biotech Applications
  • Enabling Multi-Range Conductivity Measurements
  • Supporting Multi- and Single-use Systems

The C800 converters are for optek digital conductivity sensors ACS60 or ACF60 and pH-electrodes, they are designed for continuous monitoring of pH and conductivity. The C800 series is available with one or two channels in variants for one or two conductivity probes and one mixed variant for conductivity and pH. Operation and programming is simple and intuitive via push buttons on the front panel and full text menus in 9 languages. The converter parameter set can be read out and stored via a USB connection on the front panel, which allows for quick configuration of several instruments. The C800 software is dedicated to electrochemical sensors and their specific calibration and measurement setup.

C800 Configuration C820 C821 C822
Conductivity (optek ACF/ACS) 1 1 2
pH Probe - 1 -
Power supply 24V checkmark checkmark checkmark
mA-outputs 3 6 6

2 channel electrochemical measurement converter
Ready for use with pre-calibrated conductivity sensors and pH electrodes

USB-C front side access
For cloning of standard configurations and firmware updates, access to event logger data

Membrane keyboard (navigation keys)
Keyboard designed for operation with gloves

Low reflection-, bright LED graphic display
View all measurement values at a glance

Small footprint
Compact stainless steel housing for integration in small cabinets

C820: 1 Conductivity sensor (optek ACF, ACS), 3 mA outputs

C821: 1 Conductivity sensor (optek ACF, ACS), 1 analog pH electrode, 6 mA outputs

C822: 2 Conductivity sensors (optek ACF, ACS), 6 mA outputs


Front panel mounting in control cabinets

Dimensions front: 110 x 110 mm (4.33 x 4.33 in.)

Cut-out dimensions: H 92 mm (3.62 in.) W 92 mm (3.62 in.) D 130 mm (5.12 in.)

Material: stainless steel / polyester / ABS / PUR-foam

Protection: front IP66 / rear IP20 (mains supply secured against accidental touching)


3.5" LCD graphic display (320 x 240 pixel), Monochrome display

Backlight: LED (white)


membrane keyboard (navigation keys) Software based menu operation


1 LED (green):power on

1 LED (red-flashing):system failure


up to six 0/4 to 20 mA (NAMUR)

functionally galvanically isolated (min. 500 V DC) for connection to SELV / PELV

accuracy: < 0.5%

resolution: < 0.05%

load: < 500 Ohm

Digital outputs

2 x (NC/NO)

Min. switching voltage: 5 V DC

Max. switching voltage: 30 V DC

Max. switching current: 500 mA

USB interface

USB type C interface (frontside) for data exchange (copy of parameter sets, firmware update, eventlogger read-out)

File system format: FAT32

Storage medium: USB-C stick (not included in delivery)

Conductivity inputs

Inputs for one or two optek conductivity sensors ACF/ACS series

measuring range: 0- 10 µS/cm to 850 mS/cm (depending on optek ACx sensor connected)

resolution: 0.001 µS/cm

integrated temperature sensor: Pt1000 (RTD)

accuracy: ±0.25 °C at 25 °C (77 °F)

pH input (only variant C821x)

Input for one pH electrode, model C821

measuring range 0 - 14 pH

accuracy: ±0.01 pH

resolution: 0.01 pH

resolution Pt1000: 0.04 K

resolution Pt100: 0.4 K

diagnosis: glass impedance, diaphragm breakthrough

measurement response time:

  • diagnostics enabled: < 3 s
  • diagnostics disabled: < 1 s

Cable lengths

2, 3, 5, 10, 15, 20, 30 m

(7, 10, 16, 33, 49, 66, 98 ft)

max. cable length at pH depends on the pH electrode

Power supply (fixed, secured against accidental touching)

Nominal voltage : 24 V DC

Input voltage range : 19.6 V DC to 30 V DC

Voltage supply tolerance during operation : ± 20

Power consumption maximum : 13 W

Inrush current (< 0.5 ms) : 16 A

Ambient conditions

Temperature during operation (no direct sunlight):

- converter: -10 to 55 °C (14 to 131 °F)

Temperature during transport (no direct sunlight): -20 to 70 °C (-4 to 158 °F)

Software languages

English, German, French, Spanish, Russian, Portuguese, Chinese, Japanese, Korean

Data given are subject to changes without prior notice.

C800 Product Information

Visit our documentation page to view a complete list of translated documents.