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When selecting a output line reactor, its function shall be firstly determined, then the reactance ratio can be selected according to its functions, finally, the output line reactor capacity is selected according to the capacitor capacity (reactor capacity is equal to the capacitor capacity multiplied by reactance ratio). Selection of a reactor is complex, power grid quality and parameters, capacitor parameters shall be determined.

ATO sells VFD's power range from 1/2hp to 300hp, include single phase input and output VFDs from 1/2hp to 7.5hp, 110v/120v input VFDs from 1hp to 7.5hp, single phase input to three phase output VFDs from 1/2hp to 10hp, three phase input/output VFDs from 1hp to 300hp. All VFDs are manufacturer direct sale and quality guaranteed. Widely used in fans, pumps, lathes, cable machinery, printing and dyeing equipment, chemical machinery, plastic machinery, etc. The following are ATO variable frequency drive price lists for your reference. If you want more information, please go to ATO VFD products page.

Solid state relay (SSR) is a non-contact switch which drives a high-current load with a small control signal. The solid state relay consists of three parts, namely, the input circuit, the isolation (coupling) and the output circuit.Compared with the electromagnetic relays, solid state relays are characterized with high reliability, no contact, no spark, no noise, strong anti-interference ability, long lifetime, and fast switching speed. Now SSR are widely used in automation equipment, CNC machines, remote control system, instrumentation, medical equipment and so on.

A device that converts alternating current with constant voltage and frequency into alternating current with variable voltage or frequency is called "variable frequency drive". VFD has the functions of voltage regulation, frequency modulation, voltage stabilization, speed regulation etc. VFD is generally used to control 3 phase AC motor in variable speeds. Now the three phase 220v-240v motor can run on single phase 120v power supply. ATO offers you 110v/120v input, 220v/230v/240v output VFDs. It can not only realize single phase input & output, but also convert single phase to three phase.

Measurement method of a safety relay's DC resistance with a digital multiemter is similar to that with a pointer multimeter. According to the nominal DC resistance of safety relay, place the multimeter in an appropriate resistor and connect two test pens to the leading wire of the relay coil, then measure the resistance. Comparing the measurement result with the nominal resistance, if the error is within ±l0%, it's normal. If the resistance is obviously smaller, partial short-circuit fault exists in the coil; If the resistance is zero, the coil is short circuited; If the multiemter shows "1", the coil breaks.

Safety relay has special color, generally yellow. Current safety relay acts reliably and flexibly, it's mainly used to control the power supply circuit. When an emergency occurs, the circuit controlled by the safety relay is disconnected by pressing the emergency stop switch, thus ensuring safety.

Safety relay is the main component of electric locomotive control circuit and monitoring protection system. When the electrical components or connection wires in the main circuit or auxiliary circuit break as the electric locomotive is running, the safety relay of corresponding monitoring protection system can transfer the fault into electric signal. On one hand, the electric signal will be fed back to the opening coil of main breaker to trip the main breaker, thus cutting off general power supply of the electric locomotive to protect it. On the other hand, the electric signal will be fed back to signal device (including mechanical signal and electrical signal) and make it to display different fault conditions, thus guiding the electric locomotive conductor to deal with faults timely and correctly. In this respect, the safety relay doesn't directly control the main circuit or auxiliary circuit, but it's of great importance to the electric locomotive.

Measure coil resistance, resistance of a power relay coil can be measured with the R×10Ω band, thus judging whether the coil has open circuit. Measure actuation voltage and actuation current, with an adjustable stabilized voltage supply and ammeter, the power relay can be input with a voltage while the ammeter can be connected in series to monitor. Slowly increase the power supply. Voltage and record the actuation voltage and actuation current when the power relay is attracted. For accuracy, more operations can be repeated to get the average value. Measure release voltage and release current, connect wires as the test above. When the power relay is attracted, reduce the power supply voltage slowly and record the voltage and current as hearing the relay to release again. More operations can be repeated to get the average value.

Understanding the infrared thermometers’ working principle, technical specifications, working conditions, operation and maintenance is the basis for users to correctly select an infrared thermometer or use it. An infrared thermometer consists of optical system, photoelectric detector, signal amplifier, signal processing and display output. The optical system of infrared thermometer accumulates the target infrared energy in its field of view. And the size of field of view is determined by the optical components and location of the thermometer. The infrared energy is focused on the photoelectric detector and converted to corresponding electrical signal. The signal is corrected by the amplifier and signal processing circuit according to the algorithm inside the instrument and the target emissivity and then is converted to the temperature value of measured target.

Infrared temperature measurement technology plays an important role in production, product quality control and monitoring, on-line fault diagnosis and safety protection, as well as energy saving. Compared with the contact-type temperature measurement method, infrared temperature measurement has the advantages of fast response time, non-contact, safe use and long service life. Non-contact infrared thermometer involves three major series of portable, on-line and scanning thermometer, with various accessories and computer software. Moreover, each series has different types and specifications. Among these thermometers with various specifications, it is very important for users to choose a correct type of infrared thermometer.

Iron core of the AC contactor is usually laminated by silicon steel sheet, so as to reduce the eddy current and hysteresis loss generated by alternating magnetic field in iron core, avoid the iron core overheating. However, iron core in the DC contactor's coil would not generate eddy current and there is no heating problem in DC core, so the iron core can be made of a complete cast steel or cast iron. Coil of DC circuit has no inductance, so the coil has more turns, thus leading to large resistance and copper loss. In order to keep a good heat dissipation for the coil, the coil is generally made into a thin and cylindrical shape. Coil of AC contactor has less turns and small resistance, but the coil also gives heat, so the coil is generally made into a fat and short cylindrical shape. Meanwhile, a clearance is left to facilitate heat dissipation while avoiding the coils from being burned out. In order to eliminate vibration and noise generated by electromagnet, a short circuit ring is embedded on the surface of static iron core of the AC contactor, while the DC contactor doesn't need a short circuit ring.

How to choose a right infrared thermometer? The first thing to think about is performance indicators, such as temperature range, spot size, working wavelength, measurement accuracy, response time, etc. Environmental and working conditions are also taken into account, such as ambient temperature, window, display and output, protection accessories, etc. Other factors, including convenience, maintenance and calibration performance and price, etc., also affect the selection of the infrared thermometer.

Rated primary voltage of the current transformer shall be in consistent with the rated voltage of the system. Rated primary current of the current transformer shall be 20%~120% of its normal load current. Secondary loads of the current transformer, such as instruments and relay, consume a power or impedance less than rated capacity corresponding to the selected class of accuracy, otherwise the class of accuracy will reduce. A proper class of accuracy shall be selected for the current transformer according to the requirements of measurement and protection.

ATO load cells have low capacity and high capacity, high accuracy, good output symmetry and high eccentric load resistant. Load cells can be applied for batching scale, crane scales, rail weighbridge, hopper weigher, button tester, force gauge and other special weighing instruments. Here is an ATO load cell price list for your reference. For more products information, please check the directory of load cells.

The secondary side is not allowed for open circuit. Once it's open circuited, current I1 at the primary side would fully turn to magnetizing current, φm and E2 would increase sharply. As a result, the iron core would occur supersaturation magnetization, heat seriously and even burn out coils. Meanwhile, supersaturation magnetization of the magnetic circuit would increase errors. Under normal operation, secondary side of the current transformer is nearly short circuited, if it's broken suddenly, the excitation electromotive force increases sharply, the magnetic flow in the iron core shows seriously saturated flat waves. As a result, the secondary side winding would induce high spike waves when the magnetic flow passes through zero, it can be thousands or even tens of thousands of volts, thus endangering the personnel safety and insulation performance of instruments.

Soft starter is used for controlling AC induction motor in soft start & soft stop. It applies to various squirrel-cage asynchronous motor control of load, the motor can smooth starting under any working conditions, protect the drag system, protect motor from inrush current and voltage impact, ensure reliable motor starting. Smoothly soft stopping function can effectively solve the inertial system surge problem, and eliminate the drag system of inertial impact.

Common fault for the iron core of an AC contactor is about the large noise. If it's caused by insufficient coil voltage after inspection, adjust the power voltage. If it's caused by bad contact between contact surfaces of dynamic and static cores, make contact surfaces smooth to ensure a good contact. If the noise is caused by the break of short circuit ring, replace or weld the short circuit ring. Another common fault is that the armature doesn't fall when powering off. This may be caused by small spring pressure between contacts, adjust the contact force please. If it's caused by block of armature or mechanical part, remover the barrier. There should be a clearance of 0.1～0.2mm in the central pillar of E-shaped core, if the clearance disappears due to iron core wear, the iron core may be stuck, repair the central pillar plane of the E-shaped core.

Oil leakage is a common problem for gear motor, and the problem may be caused by box quality, lubricating oil quality, oil seal quality and air pressure outside and inside the box. Meanwhile, excessive lubricating oil will also lead to oil leakage. Once the oil leakage occurs in the gear motor, corresponding measures should be taken, and this paper ATO will introduce the solutions for stopping gear motor oil leakage.

Gear motor is widely used in the metallurgy, mine, light industry, chemical industry, steel industry, cement, printing, sugaring, food industry, construction, lifting transportation and fan industry. Working environment of these industry may be damp, and damp environment will directly affect the operation of gear motor. How to keep your gear motor dry when works in such a damp environment?

In primary treatment, the suspended solid pollutants in the sewage will be removed, and most physical treatments can only meet the requirements of primary treatment. After the primary treatment, 30% BOD can be removed from the wastewater. It doesn’t meet the emission standard. Primary treatment is a pre treatment of secondary treatment.
In secondary treatment, colloid and dissolved organic pollutants (BOD, COD) in the waste water will be removed, and the removal rate can be higher than 90%. The organic pollutants meet emission standards. Use pH meter to monitor whether the emissions of organic pollutants are up to standard.
In tertiary treatment, non biodegradable organic pollutants, N, P and other soluble inorganic substances that lead to eutrophication of water bodies are further processed. Main methods are biological nitrogen and phosphorus removal method, coagulant sedimentation method, sand filtration method and activated carbon adsorption method.