Enclosure:
The enclosure can be categorized into indoor and outdoor types.
For indoor applications, considering heat dissipation and maintenance concerns, it's generally advisable not to add an enclosure if there is sufficient installation space. However, if needed by the user, an enclosure can be provided, featuring multiple observation holes. The enclosure can also be painted in the user's preferred color.
Enclosure protection ratings are typically IP20 or IP23. IP20 prevents the ingress of solid foreign objects larger than 12 mm and protects against accidental shocks. In addition to the functions of IP20, IP23 can also prevent water drops from entering within 60 degrees from the vertical, which is suitable for outdoor installation. The material of the enclosure is divided into ordinary steel sheet, plastic injection molding, stainless steel sheet, aluminum alloy composite sheet, etc.
Temperature Controller:
All transformers are equipped with an overheating protection device. These protection devices detect and control the temperature of the transformer by means of a PT thermistor built into the low-voltage coil and outputs a digital signal via the RS232 / 485 communication interface. The device provides the following functions:
1. During the operation of the transformer, the temperature value of
the three-phase winding is displayed on a circuit.
2. Display the temperature value of the hottest phase winding.
3. Overtemperature alarm and overtemperature shutdown.
4. Audible and visual alarm and fan start.
Air Cooling Device:
1. The cooling method for the dry-type transformer can be divided into natural air cooling (AN) and forced air cooling (AF).
2. In natural air cooling (AN), under normal operating conditions, it can continuously deliver 100% of the rated capacity.
3. In forced air cooling (AF), under normal operating conditions, it can achieve a 50% increase in capacity, suitable for various emergency overload or intermittent overload operations. Due to the greater increase in load loss and impedance resistance, continuous overload operation with forced air cooling (AF) is generally not recommended.
Copper bar:
1. In general, the incoming and outgoing modes of the cables are divided into upper incoming & outgoing, lower incoming & outgoing, and side incoming & outgoing.
2. For a transformer with rated power ≤ 200KVA, the conventional
outgoing mode is still used, and the side outgoing line is connected by the user with a cable.
3. If the rated power is ≥ 1600KVA, a, b, and c use double-row feeder lines with a spacing of 10 (1600200kva) or 12 (2500kVA).
4. Since the zero line is at the top of the transformer, it is recommended that the transformer zero line still enters the switchgear from the top if the zero line is brought out from the bottom of the switchgear.