I. Calibration basis of sf6 relay
Related companies attach great importance to the regular inspection of sf6 relay. Relevant requirements clearly stipulate that sf6 relays should be periodically calibrated at a period of up to 2 years. The connection method between the sulfur hexafluoride density relay and the switchgear body shall meet the requirements of not disassembling the density relay.
Because the sf6 relay is the same as other pressure gauges, its alarm and blocking values will drift to a certain extent after using for a period of time.
In addition, because the contacts of the density relay do not act frequently, the contacts may be insensitive or fail. If it is not inspected, there is a safety hazard.
II. Reasons for the quality problems of sf6 relay
1. The anti-seismic performance itself is not good enough. After the switch is switched on and off strongly, the pointer will be stuck, the contact will be permanently ineffective (no action or keep moving) and the deviation will exceed the standard.
2. Due to oil leakage, its anti-seismic performance is reduced. After the sf6 relay switch is strongly impacted, the pointer will be stuck, the contact will always fail (not operating or always operating) and the deviation will exceed the standard.
3. Since the contacts of the commonly used relays are magnetic-assisted electrical contacts, the closing force of the contacts is small, and the time is a little longer. Once the contacts are oxidized, the contacts will be blocked or unreliable.
For the oil-free type, the magnetic-assisted electric contact contacts are exposed to the air, which is very easy to oxidize or accumulate dust, and the contacts are easy to contact poorly or fail.
For the oil-filled type, although the sf6 relay magnetic-assisted electrical contact contacts are immersed in silicon oil, the contact performance will decrease after a long time and after several actions. In addition, the oil film has an insulating effect, and the contacts will also be Poor or unreasonable contact.
4. Due to its own manufacturing quality problems, the temperature compensation is inaccurate, and the error is serious (over-compensation or under-compensation).
5. Due to insufficient aging or material problems, it will drift over a long period of time and the accuracy will be severely high (the stress is not eliminated).
6. Due to design defects, the sf6 relay will fail at low temperatures (never operate).
7. Due to design defects, the action and display value will be severely deteriorated at high temperatures.
8. For the relative cavity density relay, due to internal or external reasons, the standard cavity will leak air, causing a large error in the action value or failure.
9. Due to severe vibration during transportation, the relay will fail and the accuracy will deteriorate.
10. Due to the quality of the components and the longer time, the sf6 relay may fail and the accuracy will deteriorate.
11. Since the vent hole of the shell is not loosened or the shell is sealed, there is a change in the pressure inside the shell, which changes the accuracy.
12. Due to the erosion of rain or corrosive gas, the relay will fail and the accuracy will deteriorate.
13. Due to improper use, it will also affect the use (such as improper installation location).
14. Due to process problems, the sf6 relay will fail or the accuracy will deteriorate.
15. In order to reduce costs, switch factories or relays choose inferior products or components.
16. Electrical performance: caused by insulation problems.
17. The sealing performance of sf6 relay causes quality problems.
