(1) Temperature error. This refers to the change of the length of the scale and the density of the working fluid due to the change of ambient temperature, and the former can be ignored in general, and the latter should be appropriately corrected. For example, when water is changed from 10°C to 20°C, its density changes from 999. 8kg/m^3 reduced to 999.8kg/m^3 ...

Turbine flowmeter is a kind of speed appearance, it has high precision, good repeatability, no zero drift, high range ratio, simple structure, few moving parts, high pressure resistance, wide measurement scale, small size, light weight, small pressure loss, convenient repair and other advantages, turbine flowmeter has high quality ...

Q: 250KW ATV61 with 250KW fan, when decelerating to low speed, OPF (motor missing three-phase) problem will be reported occasionally. There are no contactors or switches between the inverter and the motor. Answer: This situation seems to be a problem with the inverter, which is a false alarm. Not really! The fan is decelerating ...

PHF: 1. The power supply of the inverter is not right or the fuse is blown; 2. There is a transient problem in a certain phase. 1. Check the power connection and fuse; 2. Reset. USF: 1. Power supply voltage undervoltage; 2. Instantaneous voltage drop; 3. The load resistor is damaged. 1 Check the power supply voltage; 2 Substitutions ...

Before preparing to do circuit board repair work, you should prepare some things and appearances to help repairers better carry out circuit board repair operations, according to our circuit board repair training center for many years of experience has shown that prepare some necessary circuit board repair things and appearance, to be able to reach ...

Schneider Barrier Features: First of all, Schneider Barrier Switch can be used to block the power supply, it is able to disconnect the live equipment from the high-voltage maintenance equipment, and it can also see a significant disconnection point on it. Secondly, the Schneider barrier switch can be used with the circuit breaker to change the operation of the system.

Schneider structural circuit breaker is not stored (check the power supply of the energy storage motor, if it is normal, check whether it can be manually stored for energy) MX shunt coil live (disconnect MX coil power) The MN coil is not charged or faulty (a voltage higher than 0.85Un is applied to the MN) The circuit breaker is latched in ...

The system power is equal to the product of the inverter power and the motor power, as long as both are operating at a higher power, the system power is higher. From the power point of view, when selecting the power of the inverter, the following points should be noted: ...

a. Output frequency scale. The output frequency scale that can be controlled by the general inverter is generally 0.1Hz, and the highest frequency is different according to the functional indicators of the inverter, generally 400Hz, and some models are 650Hz. No matter how high the output frequency is, it belongs to the scale of high-frequency inverter. ...

The appearance of the instrument plays a very important role in the air separation equipment and gas purification process, and it is indispensable for the adjustment of the air separation process and the detection of product quality. Because there are different types of on-line profiles for monitoring targets in different gaseous media at each stage of the ASU process, the ...

In order to ensure that the APCUPS power supply can continue to supply high-quality power to the computer even in the event of a power outage, it is important to equip the battery backup battery. When the load is not allowed to be powered, the UPS battery backup time in the communication room should be greater than the time from the mains power interruption to the rehabilitation or to the generator set is positive.

1. About the management of higher harmonics on the output side of the inverter The magnetic noise skills brought about by the communication harmonic components contained in the output waveform controlled by PWM control have been increasingly used in various inverters, such as the selection of higher frequency switching components, the installation of filter devices at the output end of the inverter, etc.

A. Methods of Communication: (1) Radiation disturbance (2) Conduction disturbance B. Immunity Methods With regard to nuisance signals transmitted by radiation methods, they are primarily weakened by wiring and shielding the radioactive source and the disturbed lines. About Tong ...

First, it is a fan/pump load Second, the device itself has a power-saving function (software support) Third, we need to work for a long time The above are the three conditions that reflect the results of power saving. If it is said that the power frequency of the inverter is energy-saving without conditions, it is ...

rectifier Many converters use diodes, which convert the power frequency power supply to DC power. It is also possible to form a reversible converter with two sets of transistor converters, because the purpose of the power target is reversible and can be regenerated for operation. Flat wave back After the rectifier rectification ...

1. Why can the rotation speed of the motor be changed freely? Motor rotation speed unit: r/min number of rotations per minute, can also be expressed as rpm. Example: 2-pole motor 50Hz 3000 [r/min] 4-pole motor 50Hz 1500 [r/min] Conclusion:...

From the perspective of skills alone, the control method of the low-voltage inverter also indicates its skill portal to a certain extent. Here, we've broken down the following manipulation methods: 1. Sinusoidal pulse width modulation Sinusoidal Pulse Width Modulation (SPWM) is characterized by the simple structure of the control circuit, the cost of ...

1. The power supply voltage of the secondary load is 0V. There is no response after the inverter is powered on, there is no indication on the operation display panel, and the 24V and 10V voltages of the measurement and control terminals are 0V. Check that the charging resistance or pre-charging circuit of the main circuit is correct, which can be identified as a switching power supply fault. The overhaul process is as follows: 1 ...

1. The output of the inverter is controlled by PWM (pulse width modulation, similar to high-speed switching), so high-frequency leakage current will occur. The PE points of the three transmission equipment of the inverter, the pre-power supply transformer and the motor must be connected together and then grounded consistently. Frequency conversion...

A frequency converter is a device that converts power to other frequencies of power supply. The power frequency of our country is 50Hz, in the field of motors, in order to change the speed of the motor, or other performance changes, many motors choose inverter power supply. The inverter is a supporting operation with the inverter motor.

1. The instrument test has a total of YN winding three-phase test, YN winding three-phase phase-by-phase test, low-voltage winding magnetization method test of iron-core five-column low-voltage angular transformer, low-voltage winding phase selection test and general four-terminal method of ironcore three-column low-voltage angular transformer. ...