1. What is the standard size of the cable phase separation?
In principle, we require the cable to be split between 1.2m - 1.5m. But can be treated according to the circumstances. For specific equipment, we recommend:
1) bus type cable branch box requirements phase length not less than 1.2m.
2) the outlet pipe of the ring breaker is longitudinally aligned, and the phase length shall be determined on the basis of C phase during the phase separation.
2 why should the copper shield be wrapped with copper tape at the end of the copper shield after the separation?
This is done to prevent copper shielding from falling. In order to ensure that the cable below the cable head has its original characteristics after installation, the copper shield should be shrunk inside the shrink (cold) shrink sleeve. Such as copper shield scattered, you need to restore, and can not maintain the original degree of fit.
3. What is the function of copper shield?
Normally, it acts as a capacitive current and acts as a shielding electric field.
4, all stripped of the semi conductive layer will have what kind of consequences?
In the field to do cable, it is often in accordance with conventional practice will be more than half of the trigeminal gloves conductive layer stripped of all, so it is very dangerous. Because after transmission, the branch gloves, the stress tube and the stress cone between the cable surface will produce induction. In this case, if in accordance with the correct approach to pick up the American cable head ground, long time after the operation, the induction electric cable grounding cable will discharge, severe burns and even discharge burning heat shrinkable sleeve. Therefore, the semi conductive layer must be kept in strict accordance with the process size. See question 29.
5, the rough production process will produce what kind of consequences?
In the construction process, if you do not pay attention to details, it will bring many hidden dangers to the safe operation of the equipment. Such as: the copper shield cable stripping and semi conductive layer, the force is too large or uneven, injury to the semi conductive layer or the main insulation; not a scratch on the main insulation and incomplete treatment will reduce the creepage distance, easy to cause serious equipment burning or explosion.
6, what are the consequences of a reverse loading or mismatched stress cone?
The stress cone installation will cause the insulation distance within the T body to be smaller, and the semi conductive layer will not overlap and destroy the full screen. If the stress cone is not matched, the stress cone will be reduced, the stress and the uniform electric field will be eliminated, the electric field stress will be too concentrated, and the partial discharge will be easy to occur. See also question 7 for handling.
7, forget installation stress cone should be how to deal with?
The principle is sawed off pressure terminal re installed in special circumstances in the grease should be applied inside surface of stress cone and the terminal, and the stress cone is installed in the terminal, the premise is to smooth, no burr. This method is forced to use, usually in time permitting, should try to redo.