Breaker closing and closing synchronic test significance and test method - News - Global IC Trade Starts Here Free Join

Photocoupler

Concurrent test significance

The circuit breaker division and closing synchronism refers to the degree of three-phase different periods when opening or closing. It is required that the degree of this different period is as small as possible, and the circuit breakers are severely closed in different periods, which will cause lines or electrical equipment. The non-full-phase access or resection may cause an overvoltage that jeopardizes the insulation of the equipment, which may also cause damage to the contacts of the circuit breaker, and cause the generators and transformers to be in parallel at the same time. Therefore, after the handover and overhaul, the circuit breaker must be tested for three-phase synchronization.

The test generally adopts the synchronous bulb indication method. It can also measure the three-phase operation time by using three electric stopwatches according to the site conditions or use the electromagnetic recorder to check the action synchronism of the circuit breaker.

Only the simultaneous bulb indication method will be described here. There are three lamp methods and six lamp methods in the lamp indicator method, and the wiring is as shown in the figure. Among them: Figure (a) Three-lamp method, suitable for circuit breakers with one static contact per phase; Figure (b) Six-lamp method, suitable for circuit breakers with two static contacts per phase. During the test, the synchronism of the three phases is judged by the order in which each phase of the bulb is illuminated.

For circuit breakers with two static contacts, in addition to judging the three-phase synchronism, it is also possible to check whether the two pairs of dynamic and static contact contacts in each phase are also in the same period; during the test, the circuit breaker should be manually operated, slowly Touch or separate the moving and static contacts to carefully observe the brightness of the light bulb when it is bright or extinguished, and make a mark on the corresponding lifting rod at the moment when the contact is just divided or just finished, and finally measure the relative distance between the marks. The relative distance between the first light and the last bright light bulb is the maximum closing (or opening) error. If the error is large, adjustments should be made until the bulb is on or off at the same time. The test can be used with direct power or low voltage 36V AC power supply; if using 220V power supply, care should be taken to prevent electric shock.