Industrial online conductivity meter TDS meter EC transmitter

الوصف

DDM200 series conductivity transmitter


DDM seriesindustry conductivity transmitter is a kind of process meter which measure the aqueous solutions conductivity in industrial processes.
Conductivity is an important indicator of water purity. The amount of impurities of boiler water, demonized water, distilled water and wastewater is measured by conductivity. The concentration of acids, alkali and salt solution in various chemical liquid, and the dissolved oxygen in boiler water can all be measured by conductivity.
DDM200 series conductivity transmitter is the economic model, it integrated the industrial sensor, transmitter and instruction meter as a whole, innovatively designed and can work reliably.

1. With 4~20mA or Modbus/RTU(RS485), can be easily connect to the control system such as PLC and DCS.
2. Modular electronic unit is reliable with dust proof and water proof. With strong anti interference capability.
3. Sensor and other parts is connect by VP or BNC header, easy for maintenance.
4. Digital display optional, easy and intuitive.

Measurement scale	0~20uS/cm, 0~200uS/cm, 0~2000uS/cm, 0~200mS/cm, 0~400mS/cm, 0~600mS/cm
Accuracy	0.1μS/cm±1Digit
Drift	≤ 0.5% / 24 Hour
Load characteristics	For 4~20mA,0~600Ω,16-38VDC
Operating pressure	< 0.6MPa
Medium temperature	-10 ~ 80℃, 80 ~180℃
Environmental conditions	Ambient temperature: -10 ~ 55 ℃
	Humidity: ≤ 95%

1. The concept of conductance and conductivity

Electrolyte solution is like the metal conductor, is a good conductor for electricity. Therefore, current flows through the electrolyte, there must be resistance effect, and in accordance with Ohm's law. However, the resistance temperature characteristics of liquid is contrast with metal conductor, its temperature characteristic is negative. As distinguished from the metal conductor, the conductance of electrolyte solution is expressed by the reciprocal of the resistance, and the conductivity is the reciprocal of the resistivity. If G represent conductance, S represent conductivity, then there is the following formula:
Where:
R ─ Liquid resistance, Ω.
ρ ─ Resistivity, Ω · cm.
L ─Distance between plate of the electrode,cm.
A ─ Electrode plates cross-sectional area, cm2.
G ─ Conductance, S (1S = 1Ω-1).
S ─ Conductivity, S · cm-1 or (Ω · cm)-1
k ─ Electrode constant, cm-1.
When L = 1cm and A = 1cm2, G = S. Means that 1 cm3 volume of the solutions conductance is conductivity. If fill 1 molars solution in the 1 cm3 volume, then its called molar conductivity.
 

1. The conductivity measurement

Two mutually insulated electrode formed the conductivity cell, in which, fill with target medium. Pass through alternating current with constant voltage, to form the electrical circuit. Fixed voltage and electrode size, the loop current I is a function of the conductivity:
I0 = f (s) = K · S + d
Where K is the slope of linear equation, and related with power supply parameter of the conductivity cell. Change the power supply parameters, you can change the slope (measuring range). Linear equation fixed the range of output current, so when S = 0, the constant d can be calculated, which can determine the current value that flowing through the target medium. So the conductivity can be measured by current. See figure below.
In the electrolyte solution, the larger of the ion concentration per unit volume, the greater of the conductivity; The higher of the valence of ions, the greater of the conductivity; The faster of the ion mobility, the greater of the conductivity. The conductivity of the absolutely pure water is 5.5 × 10-8 S/cm (25℃). The relationship of conductivity for different aqueous solution is as follows:

بلد:	China
نموذج رقم:	DDM200
سعر فوب:	199 ~ 499 / Piece ( Negotiable ) (قابل للتفاوض) أحصل على آخر سعر
الموقع:	-
سعر الحد الأدنى للطلب:	199 per Piece
الحد الأدني للطلب:	1 Piece
تفاصيل التغليف:	Carton.
موعد التسليم:	In 15 days after payment.
القدرة على التوريد:	1000 Piece per Month
نوع الدفع:	PayPal, Western Union, T/T
مجموعة المنتج :	Water Analysis