The principle and maintenance method of Kyushu space analysis conductivity meter
First, the principle of conductivity meter
Conductivity is a digital representation of the ability of a solution to conduct current. The conductivity of water has a certain relationship with the amount of inorganic acids, bases and salts contained in it. When their concentration is low, the conductivity increases with the increase of concentration. Therefore, this index is often used to estimate the total amount of ions in water. Concentration or salt content.
Conductance (G) is the reciprocal of the resistance (R). Therefore, when two electrodes (usually a platinum electrode or a platinum black electrode) are inserted into the solution, the resistance R between the two electrodes can be measured. According to Ohm's law, when the temperature is constant, this resistance value is proportional to the electrode spacing L (cm) and inversely proportional to the cross-sectional area A (cm2) of the electrode, namely:
R = Ï Ã— (L / A)
Where Ï is the resistivity, which is a resistance of 1 cm 2 in length and a cross-sectional area of ​​1 cm 2 , the size of which depends on the nature of the material.
According to the above formula, the conductance (G) of the conductor can be expressed as follows:
G =1/R=(1/Ï)×(A/L)=K×(1/J)
Where K=1/Ï is called conductivity and J = L/A is called electrode constant.
Electrolyte solution conductivity refers to the conductance of a solution of 1 cm3 between two parallel electrodes separated by 1 cm. It can be seen from the above formula that when the electrode constant (J) is known and the solution resistance (R) or conductance (G) is measured, the conductivity can be determined.
Common faults and maintenance methods for conductivity meters:
(1) Power section
1. When the low-voltage AC power supply fails, the indicator light and each filament are not lit. Inspection can be carried out in the order of power input, transformer primary, transformer secondary low voltage, etc.
2. The high-voltage DC power supply can be illuminated in the indicator light and each filament, but the electric eye tube does not emit green light, and when the replacement of the new electric eye tube is invalid, the problem can occur in the high-voltage DC power supply part. When checking, the universal voltage of the universal meter can be used for 500 V. The two anode voltages of the rectifier should be measured to be about 250 V to the ground. Otherwise the problem lies in the secondary high voltage or wiring of the transformer. If there is electricity, measure the cathode of the rectifier tube with a DC voltage of 500 V, which should be about +200 V to the ground. If there is no DC voltage or the voltage is low, the rectifier or filter capacitor should be replaced. And connect the contacts.
(2) Failure of the oscillator and cathode output
When the accurate balance point cannot be measured by the high cycle, the oscillation tube and the cathode output tube can be replaced first. If the problem cannot be solved, the voltages and wirings of the two tubes must be measured. The oscillating tube anode should be approximately ten 150 V and the second grid should be approximately + 60 V. The anode of the cathode output tube should be approximately +250 V. Reusable high-impedance headphones or speakers (low-resistance through the output transformer) can be monitored, or an oscilloscope can be used to track and check each signal point. This will reveal the problem.
(3) Failure of the bridge part
The performance is that the indicator flashes unstable when the reading knob or the override button is rotated during the measurement, whether the high or low cycle is used, or the balance point is not found at all.
1. Check the electrode system in the bridge first
The electrode is removed and connected to a known resistance of about 1000 ohms. If a resistance of about 1000 ohms can be measured, the problem is at the electrode or wiring. Replace or repair the electrode system. If you can't measure it, you can continue to check it.
2. Reading button section
Sometimes the sliding wire resistance inside the reading button is not well contacted, and the contact point can be cleaned with a clean silk cloth, so that all parts can be in good contact.
3. Multiplier button section
Due to the misalignment or poor contact of the internal band switch, it can be cleaned and reset by a small amount of absolute ethanol or trichloroethylene.
4. Capacitance problem
Sometimes the edge of the indicator's strip is blurred, and the bridge arm capacitance can be adjusted to be clear.
(four) indicator failure
1. The indicator action is not sensitive. At this time, the amplification tube and the electric eye tube can be replaced. If it is still not sensitive, the voltage and wiring of each pole should be checked.
2. If the edge of the indicator light band is still blurred after adjusting the electric capacity of the bridge, the electric eye tube 6E1 or 6E2 can be replaced. The green fluorescent band of the former is fan-shaped movement, and the latter is moving up and down, and the wiring is different.
Kyushu Space - a professional manufacturer of conductivity meters, ten years of focus, create professional products; ten years of intentions, to create caring services; ten years of credit, to create a trust brand, has been at the forefront of the industry, welcome customers to inquire.
Tissue Storage Box, Tissue Organizer
PP with bamboo material creates fashion and natural design.
Bamboo lid effecienly protect dust far away from tissue.
Tissue holding area is available for various size of tissue.
Three divisions can hold other small living things, besides tissue, making home much tidier.
More size and shapes are available if interested.
Tissue Storage Box,Bamboo Lid Tissue Container,Tissue Organizer,Ecoco Tissue Box
SY INTERNATIONAL (CN) CO.,LTD , https://www.syplasticbox.com