C8520.5 Toroidal Conductivity Sensor

Conductivity range from 4 to 2,000 mS/cm and TDS (total dissolved solids) from 10ppt to 1,000ppt 4…20mA and Modbus output

These B&C Electronics C8520.5 toroidal conductivity sensors measure electrical conductivity and TDS (total dissolved solids) using the inductive method.

Thanks to the analog and digital outputs, the toroidal conductivity probes can be connected to the most common PLCs or data acquisition equipment.

B&C Electronics offers the MC6587 and MC7687 multi-channel controllers that allow complete management of up to three probes, displaying measurements and messages that guide calibration and configuration.

Ranges

Conductivity ranges are configurable from 4 mS to 2,000 mS. TDS scales are configurable from 10.00 ppt to 1,000 ppt.

It is also possible to associate a scalability factor from the 10% to the 100% to obtain intermediate full scale values in the 4/20 mA current loop through digital commands.

Mode of operation

The probes can be configured to operate in analog or digital mode. If connected to a master device, various operations can be performed through specific digital commands.

Analog output

The 4/20 mA current loop is proportional to the main measurement value. The current loop is galvanically isolated, for interfacing with PLC or data acquisition cards.

Serial interface

The isolated RS485 serial interface allows calibration and configuration of the probes, simultaneous transmission of conductivity, TDS and temperature measurements. The bootloader function allows the user to upgrade the probes' firmware.

Communication protocols

The B&C ASCII protocol coexists with the MODBUS RTU protocol (function 03, 06, 16) for the transmission of measurements, configuration and calibration of probes.

Filtering software

The filter software works with the sensor input signal and two selectable time constants. In order to obtain good reading stability and fast response to process changes, the user can set the response time for both small and large variation signals.

Temperature compensation

The probes include a temperature sensor for automatic compensation. The reference temperature and the temperature coefficient value can be selected digitally.

Easy installation

The C 8520.5 probe is designed for a DIN 11851-52 process connection, while the C 8325.5 model can be installed with SZ 724 to a DN40 connection. For submersible installations,

B&C Electronics offers extension tubes in various materials and lengths.

Power supply

The probes are powered with a voltage of 9/36 VDC in the current loop, powered by a PLC or data acquisition cards or by a power supply placed in series between the analog output and the acquisition device. Even in digital mode, power is supplied by the current loop.

Properties

Technical Characteristics C8325.5 – C8520.5
Conductivity scales:	0/4.000 – 0/40.00 – 0/400.0 mS and 0/20.00 – 0/200.0 – 0/2,000 mS
TDS Scales:	0/2,000 – 0/20.00 – 0/200.0 ppt and 0/10.00 – 0/100.0 – 0/1,000 ppt
TDS/EC Factor:	0.450/1,000 1/S
Scalability factor 4/20 mA:	10/100%
Sensitivity:	60/160 %
Zero:	±10 % of full scale
Resolution:	1 digit
Temperature limit:	– 5/+60 °C
Reference temperature:	20/25 °C
Temperature coefficient:	0.00/3.50 %/°C
Dual software filter:	2/220 seconds
Power supply:	9/36 VDC
Current loop:	4/20 mA isolated
Burden:	600 ohm max at 24 VDC
Digital output:	RS 485 isolated
Protocols:	B&C ASCII and Modbus RTU (03, 06, 16 functions)
Transmission speed:	2400 / 4800 / 9600 / 19200 baud
Probe ID:	01/99 (B&C protocol) 01/243 (Modbus protocol)
Probe network:	32 max.
Operating temperature:	60 °C max.
Operating relative humidity:	95 % non-condensing
Working pressure:	10 bar at 25°C / 3 bar at 65°C
Body material:	PVDF
Dimensions:	L=264 mm, D=40 mm (C 8325.5) L=307 mm, D=50 mm (C 8520.5)
Weight:	Body 267 g, cable 640 g (C 8325.5) Body 312 g (C 8520.5)
Wire:	SZ 9501 7-pin connector IP65 with 10 m to 100 m cable, PVC cover (C 8325.5)
Process connection:	DN 40 with SZ724 (C 8325.5), DN 32 (C 8520.5)
Protection:	IP 68
EMC/RFI Compliance:	EN 61326-2-3/2013 – EN55011/200