SF6 gas has good insulation and arc extinguishing properties, so it is more and more widely used in various high-voltage equipment, such as high-voltage switches, transformers, reactors, transformers and so on.
SF6 gas density has a decisive role in the insulation performance and arc extinguishing ability of SF6 gas, SF6 relay as an important component to monitor the change of SF6 gas density in operating equipment, its performance directly affects the safe operation of SF6 equipment.
Field operation of SF6 relays because of infrequent action, may be poor contact or inflexible action failure, especially the use of SF6 relays with temperature compensation, but also may be temperature compensation performance deterioration failure.
SF6 relay calibration laboratory calibration and field calibration of two kinds, field calibration due to the constraints of field conditions, the need for more careful analysis of the results of the calibration, in order to make an accurate judgment.
In laboratory calibration, the temperature and humidity do not change much, and the impact on the calibration results is relatively small.
Use the instrument to collect the SF6 relay electrical contacts at various temperatures and densities of the contact signal, automatically converted to 20 ℃ when the gas pressure value.
Observe whether it can send alarm signal or blocking break signal within the specified value of low pressure, so as to judge the SF6 relay good or bad.
When collecting the contact signal of the electrical contacts of the density relay, the signal collection line of the existing testing instrument is generally connected to the electrical contacts using alligator clips with insulating jackets.
Although the alligator clips can be connected to various types of electrical contacts (pin type, butterfly type, wire-out type), the position of the alligator clips needs to be carefully adjusted each time they are connected to ensure that they do not have a false connection.
Moreover, the gap between the electrical contacts of SF6 relays (especially the pin type and butterfly type) is small, which is not very convenient when using alligator clips and reduces the efficiency of calibration work when a large number of calibrations are needed.
At the same time, due to the signal line and the crocodile clip connection of the soldering process is not fine enough, solid, coupled with the operation of inappropriate plucking action, especially easy to cause the crocodile clip and the signal line contact disconnection, affecting the use.
In order to make up for the shortcomings of the simple alligator clip signal collection line, it can be added on top of it to facilitate the connection of the signal connector with the needle type electrical contacts and butterfly electrical contacts.
This will not only reduce the workload in the laboratory calibration, but also improve the service life of the signal acquisition line.
The other end of the collection line is made into different connectors according to the different manufacturers of test instruments, and the universal signal collection line can detect up to 4 groups of contacts at the same time.
When it is used for laboratory calibration of a large number of SF6 gas density relays, it will effectively improve the speed and accuracy of the calibration, and is robust and durable.