Installation method of flat steel for transformer neutral point grounding
Thread Content
The transformer is located in the low-voltage distribution room on the first floor, while the grounding electrodes are situated outdoors. Is it necessary to use a steel pipe when the grounding flat bar for the transformer’s neutral point passes through the wall? What protection methods does everyone use?
Grounding wires should be installed in substations; protective pipes can be used to pass these wires through walls
The last edit to this post was made by jingkong12 on 2019-4-15 at 16:12. 1. The neutral point of a single transformer can be directly grounded, but a bare conductor (such as galvanized flat steel) cannot be used to connect it to the outdoor grounding electrode； To prevent stray currents, the transformer neutral point should be connected to the main equipotential bonding plate using an insulated conductor ； Then, it is led to the outdoor grounding electrode using galvanized flat steel via the main equipotential connection plate ； Galvanized steel pipes can be used for passing through walls. 2. The neutral points of multiple transformers cannot be grounded directly; instead, a single-point grounding method should be used at the main incoming cable cabinet. That is, the N (PEN) busbar derived from the transformer’s neutral point is connected to the PE wire at one point in the main incoming cable cabinet, after which N and PE are separated completely. The connection point between N and PE is connected to the main equipotential bonding plate using insulated wires, and galvanized flat steel can be used to connect the main equipotential bonding plate to the outdoor grounding electrode ； Galvanized steel pipes can be used for passing through walls. For details, refer to GB50065-2011 \"Code for Design of Grounding of AC Electrical Installations\" and 14D504 \"Installation of Grounding Installations\".