Analysis on the method of checking the compressor capacitor

Measurement methods:

1. Use the resistance range of a pointer multimeter to roughly measure the charge and discharge time:The red and black test leads touch the two poles of the capacitor respectively. If the needle rises quickly and then slowly returns to its original position, it means the capacitor is good. If the needle does not rise or does not return to its original position after rising, it means the capacitor is bad.

2. Use the capacitance range of a digital multimeter or a dedicated capacitor to measure；The selection of compressor capacitor needs to be based on its appearance and capacity. At the same time, it is also necessary to master and understand the method of its inspection, so as to effectively help people understand and check whether there is any problem.Only in this way can we ensure whether there is a problem with the compressor capacitor that causes it to not operate normally.

High voltage chip capacitors are also known as ceramic multilayer chip capacitors.It is a production technology using ceramic powder, and the interior is precious metal palladium.It is made by plating silver on ceramics using high temperature sintering method as an electrode.The products are divided into two types of materials: high frequency ceramic NPO (COG) and low frequency ceramic X7R.NPO has a small package size, high temperature coefficient capacitance, and good high-frequency performance. It is used in highly stable oscillation circuits as circuit filter capacitors.X7R ceramic capacitors are limited to bypass or dc isolation in circuits operating at normal frequencies, or in situations where stability and loss requirements are not high. This type of capacitor is not suitable for use in AC pulse circuits because they are easily broken down by pulse voltage, so it is not recommended to use them in ac circuits.

High voltage chip capacitors are divided into three categories: 

One type is the temperature compensated NPO dielectric. NP0, also known as COG, has very stable electrical properties and basically does not change with temperature, voltage, or time. It is an ultra stable, low loss capacitor material type and is suitable for high frequency, ultra high frequency, and very high frequency circuits that have high requirements for stability and reliability.

The second type is high dielectric constant X7R dielectric. X7R is a strong dielectric, so it can produce capacitors with larger capacity than NPO dielectric.The performance of this kind of capacitor is relatively stable. With changes in temperature, voltage and time, its unique performance changes are not significant.It is a type of stable capacitor material and is used in DC isolation, coupling, bypass, filtering circuits and medium and high frequency circuits with high reliability requirements.

The third type is semiconductor type X5R dielectric. X5R has a higher dielectric constant and is often used to produce large-capacity capacitor products with larger specific capacitance and higher nominal capacity.However, its capacity stability is lower than that of X7R, and its capacity and loss are more sensitive to test conditions such as temperature and voltage. It is mainly used in oscillation, coupling, filtering and bypass circuits in electronic equipment.

Advantages: small package size, stable quality, high insulation performance, and high voltage resistance; Disadvantages: small capacity, the current MAX is 100uF, and it is easy to be broken down by pulse voltage.

Performance parameters: 1. Material NPO (COG). X7R. X5R. Y5V; 2. Capacity 0.1PF-100PF-1NF-1UF-100UF; 3. Voltage 6.3V-100V-1KV-2KV-5KV; 4. Package 0201-0805-1206-1812-2225.

Application scope: The products are widely used in module power supply, automotive electronics, communication power supply, LED lighting power supply and other fields, and have broad application development prospects.