The core temperature of a low voltage transformer increases proportionally to the applied load. Also, the core temperature rises faster as the ambient temperature increases.
In other words, the transformer core temperature rises faster than the ambient temperature when the applied load is higher.
To avoid overheating, the core temperature must not exceed a certain threshold. To do this, a fan cooling system can be used to keep the temperature below a certain level.
During its operation under load, the transformer has losses due to the passage of current in the electrical conductor. The latter, having a resistance value >0, causes part of the power supplied to the transformer to be transformed (due to the Joule effect) into losses, which translate into heating of the transformer.
This heating must be kept under control, as it could exceed the reference values and cause inevitable problems, as well as a waste of energy.
Generally the transformers that overheat excessively are those inserted in boxes.
In order to keep the losses values confined within the established ranges, New CTA provides to accessorize the transformer box with ventilation systems and temperature control (multi-sensory LED light).
Types of ventilation systems:
- When the thermal values slightly exceed the established parameters, a single fan is installed which extracts all the hot air produced by the transformer, avoiding a further rise in temperature.
- In more “extreme” situations the boxes are equipped with 2 fans, one of which extracts hot air (as in the previous case) while the other, suitably positioned, introduces fresh air (low temperature) taken from the external environment and directed towards the transformer.