Experience of using the hottest imported high volt

Experience of using imported high-voltage vacuum circuit breakers

1. the energy storage motor of Siemens 3ah high-voltage vacuum circuit breaker is often burned out reasons and improvements

(1) reasons

the energy storage motor of Siemens 3ah series high-voltage vacuum circuit breaker is often burned out, and most of them are burned out after not long use at the user's place. Other imported high-voltage vacuum circuit breakers have never had the accident of burning out the energy storage motor

we compared it with other imported high-voltage vacuum circuit breakers, and found that the power of the energy storage motor used by the original 3ah was 170W, and the minimum power of the energy storage motor used by other imported high-voltage vacuum circuit breakers was 240W (both series excited motors), and there was no margin in the power of the energy storage motor used by 3ah. This may be one of the main reasons for repeated burning

on the line, the high-voltage vacuum circuit breaker adopts an energy storage in place travel switch to disconnect the energy storage motor circuit when the energy storage is in place. However, according to the domestic conventional design, the energy storage motor circuit also needs to be connected with an "energy storage switch" (generally lal8-22x knob is selected and installed on the panel). When the "energy storage switch" is closed, the energy storage motor circuit is connected, and the energy storage is in place. The internal travel switch disconnects the energy storage motor circuit, and the energy storage motor stops. After the "closing" energy release, the energy storage motor automatically rotates to store energy; When the "energy storage switch" is opened, the high-voltage vacuum circuit breaker is closed, and the stored energy is released. Because the "energy storage switch" has been opened, the second energy storage will not start after energy release, and the energy storage spring will not be in a tension state. Although the "energy storage switch" is easy and convenient to operate, it is easy to rotate the "energy storage switch" during the energy storage process to stop the energy storage motor halfway. At this time, the energy storage spring is already in a tense state. When it starts again, the energy storage motor will start with heavy load (even locked rotor). The current is large, and there are no protective measures in the whole circuit, which is the direct reason for burning the energy storage motor

[2) improvement

change la18 - if a major breakthrough can be made in scope preparation and utilization, the 22x knob is a C45 circuit breaker, which is installed in the door (next to the high-voltage vacuum circuit breaker), and the user can only choose to store energy when opening the door. In case of misoperation when opening the door, the overcurrent protection action of C45 circuit breaker and the electric energy storage cannot continue. At this time, manual energy storage can help store energy in place (generally, the hole of the energy storage handle is not opened on the door, and now the door is open, so it is easy to store energy manually), and this note and operation method are highlighted in the "user manual". After taking these measures, there was no accident of burning the energy storage motor

2. Causes and treatment of false platform switch of Siemens 3ah5 high voltage vacuum circuit breaker

Siemens 3ah5 high voltage vacuum circuit breaker is an economic product launched recently, and the energy storage mechanism has been greatly changed. The phenomenon of "false closing" occurred several times at the user. The so-called "false closing" is to press the closing button, and the closing action is half (the main contact has not been closed yet). At this time, pressing any button will not work, and it is stuck

(1) cause

when the interlock connecting the bottom and the electric cabinet is in the closing forbidden position, the closing push rod should be blocked. There is an adjusting screw on the closing push rod, which is locked by the nut. Once the locking nut is loosened, the length of the closing push rod changes. At this time, pressing the closing button can release energy, but it is blocked by the chain mechanism halfway, forming a "false closing" phenomenon

(2 the frame capacity of the hydraulic servo system experimental machine ranges from 100 lb to several tons) processing

① remove the interlocking interface between the bottom and the electric cabinet

② pry the barrier on the rotating shaft cam with the handle of the manual energy storage rocker to release the energy in place

③ the adjusting screw on the closing push rod exits the two teeth, locks the nut, and drips glue to seal it

④ opening

at this time, it has been restored to the original state. Lift up the interlock mechanism and check whether the closing button is reliably blocked

3. Mitsubishi Vpr high voltage vacuum circuit breaker is equipped with energy storage signal output contact

Mitsubishi Vpr high voltage vacuum circuit breaker standard configuration 2 pairs of energy storage 4 It can effectively avoid the jaw slipping signal contact when clamping the sample during stretching, and has been used in the internal energy storage motor circuit. When the external energy storage status signal is required (such as installing the energy storage in place signal lamp on the panel, and outputting the energy storage in place signal to the system computer, etc.), special orders are required. The arrival time is long, and the price is much higher than the standard configuration. In fact, it is convenient to install it by yourself

[1) add a pair of energy storage signal contact steps

⑦ connect the wire on the self prepared lx5-11g travel switch

② remove the panel screws of Vpr high voltage vacuum circuit breaker and open the panel

② use M5 × The 35mm screw (first screw the nut for locking) is screwed into a screw hole reserved for the energy storage shaft. When the length of the unscrewed part is equal to that of the adjacent screw, lock it with the nut

④ unscrew the screws that originally fixed the two sets of energy storage travel switches; Fix the additional one with the original two travel switches with m4x55mm screws according to the original conditions

⑤ the pre connected wires on the added travel switch and other wires are fixed with ties and threaded to the switch socket

⑥ press the pin on the thread head and install it into the corresponding position on the socket. 34 is a common contact, 35 is a normally closed contact, and 36 is a normally open contact

⑦ manually store energy with a crank, and check the collision between the screw head on the energy storage rotating shaft and the travel switch (maintain the same gap as the original one)

[2) the steps of adding two pairs of energy storage signal contacts

are basically the same as the steps of adding one pair of energy storage signal contacts. The difference is:

① put 1 prefabricated part (nylon) shown in Figure 2 of the shutdown experiment at the upper and lower limit positions into the energy storage shaft, and use m5x50mm screws (screw the nut first for locking) Screw in the energy storage shaft through the left light hole of the part. When the remaining part is equal to the screw next to it, lock it with a nut

⑦ M5 × The 35mm screw (screw the nut first for locking) is screwed into the screw hole of the part. When the length of the unscrewed part is equal to that of the screw next to it, lock it with the nut

③ unscrew the screws that fix the two sets of energy storage travel switches, and use M4 × 75mm screws, fix the two additional travel switches together with the original two travel switches as is. 34 and 37 are common contacts, 35 and 38 are normally closed contacts, 36 and 39 are normally open contacts

④ at the place where the tension spring of the energy storage counter collides with the travel switch, use pliers to withdraw an angle to the right and the outside, so that the tension spring steel wire can move away from the travel switch during the whole process of energy storage

4. Treatment of insufficient withstand voltage of AB Nissan VD4 high voltage vacuum circuit breaker

non original VD4 high voltage vacuum circuit breaker is installed in the electric cabinet, and the relative ground (shell) withstand voltage is often insufficient. We put another layer of heat shrinkable sleeve on the original contact arm sleeve, and after this treatment, there is no problem in applying pressure resistance