Qiwei DDS-307 microcomputer conductivity meter 0~1999μs/cm

DDS-307

Conductivity meter (microcomputer type)

Introduction

Qiwei DDS-307 conductivity meter is a microcomputer-based precision conductivity meter, equipped with a temperature electrode, which can automatically compensate the temperature and maintain a more balanced experimental environment temperature. The measurement range of DDS-307 conductivity meter is (0～199.9) μs/cm; (200～1999) μs/cm; (2.00～19.99) ms/cm; (20.0～199.9) ms/cm, which can store serial number, Measured value, unit of measure and temperature value, convenient for follow-up data tracking. The measurement is stable and convenient.

Product principle

In an electrolyte solution, charged ions move under the action of an electric field to transmit electric current. Its conductivity is represented by the conductivity G, which is the reciprocal of the resistance. That is, G=1/R

The method of testing the conductivity is to insert an electrode composed of two metal plates into the solution to form a conductivity cell, and measure the resistance between the two plates. According to Ohm's law, the resistance value is proportional to the distance L (cm) between the plates and inversely proportional to the area A (cm2) of the plates. That is, R=ρ•L/A 

ρ is the resistivity, let its reciprocal be the conductivity and expressed in K, then K=1/ρ

For a certain electrode, the ratio of the effective distance L between the electrode plates to the area A of the plates is called the electrode constant of this electrode, expressed in J, that is, J=L/A 

According to the above formulas, it can be obtained:  G=K/J, that is, K=G·J

The unit of conductance G is Siemens, and the unit symbol is S.

 1S＝103ms＝106μS

The commonly used units of conductivity K are mS/cm and μS/cm.

Test Principle

The method of DDS-307 conductivity meter to test the conductance is to apply the AC Voltage generated by the oscillator to the electrode (the purpose of applying the AC Voltage is to avoid the polarization of the electrode), and a current is generated in the conductivity cell, which is consistent with the measured current. The conductivity of the solution is proportional to the current-Voltage conversion, amplification, detection, conversion to DC Voltage, temperature compensation, etc., and finally converted into a digital signal by the A/D converter, which is displayed by a microcomputer. The whole process is controlled and processed by microcomputer.

Pictures

Packing list：Host x1, Certificate x1, Manual x1, Encasement box x1

[Note]Because the manufacturer's packaging may be updated or upgraded, the detailed packaging list shall be subject to the latest standard configuration of the manufacturer.