Problems with the transformer? They are caused by the environment in which it operates

Transformers are designed and tested in laboratory conditions that reproduce those prescribed by the regulations, but sometimes the real operating conditions are very different, and unfortunately generate malfunctions of the transformer and a considerable reduction in its life expectancy.

Requirements of the legislation for the electrical substation

The environment in which the transformer operates is the electrical substation (or containment box).
The requirements for the design and maintenance of the electrical substation are contained in the CEI78-17 Standard which explains the fundamental parameters to be monitored:
- Maximum ambient temperature: 40 ° C
- Minimum ambient temperature: -5 ° C
- Air humidity: 93% non-condensing
- Dust: cleaning is recommended once a year

Naturally, the norm refers to standard parameters and the reality is very variable: places with more or less hot climate and more or less dusty places. These variations can lead to differences in environmental conditions.

The Regulations also indicate the optimal working conditions, but do not say how to reach, maintain and monitor them ... For this …….. there is Tecsystem!

How to maintain the correct temperature in the electrical cabin

If the legislation provides that the maximum temperature in the environment where the transformer operates is 40 ° C, 40 years of maintenance and assistance teach us that it is not always possible to respect this limit.
The causes that affect the temperature rise in the electrical cabinet are:
- climatic conditions (different countries face different ambient temperatures: sometimes 40 ° C is already reached by the outside air, it is easy to imagine how they can be overcome with electrical appliances that produce heat)
- inadequate electrical substation. There are cases in which the electrical cabin does not guarantee proper ventilation, thus contributing to the increase of the internal temperature
- increase in the load required by the transformer due to the increasingly frequent use of energy, compared to a few years ago, which consequently leads to an increase in the temperature of the transformer and of the air inside the cabin.
Industry studies show that every 6 degrees of temperature increase in the cabin, the transformer halves its life expectancy.

TPU SYSTEM for monitoring the conditions of the electrical substation

The TPU system (temperature, dust and humidity) is studied to monitor the environmental conditions of the cabin.

TPU SYSTEM for temperature monitoring
The TPU system monitors the temperature of the environment in which the transformer operates.
Thanks to its sensors, it detects the temperature in the electrical cabin considering both the maximum (too hot) and minimum (too cold) level. Upon detection of the anomaly, it sends an alarm to the operator and continues to monitor the temperature. In this way, in the event of a malfunction of the extractor (for cooling) or of the heaters (for heating), the TPU system will be able to send an additional alarm to the operator, allowing intervention before the system is switched off.

TPU SYSTEM for humidity monitoring

Humidity is another environmental factor that can compromise the correct operation of the transformer and the electrical devices in the cabin. In particular, beyond a certain threshold, it creates condensation and therefore loss of insulation, oxidation or corrosion of some metal components of the electrical system.
The TPU SYSTEM, as for the temperature, detects and monitors the percentage of humidity in the cabin air and activates systems for restoring the ideal conditions when the set thresholds are reached. 

TPU SYSTEM for dust monitoring

Dust is the third but no less important deterioration factor in the transformer's operating environment. Especially in association with humidity it contributes to worsening the dielectric capacity of the system, with consequent insulation losses.
The TPU system signals the excessive deposit of dust, which is difficult to predict in terms of time because the accumulation can be variable.

Other advantages of the TPU SYSTEM and network transmission

The TPU system designed and patented by Tecsystem is also equipped with two auxiliary inputs for managing sensors with NC (normally closed) contacts. An example is the connection with an anti-flood sensor, which in the event of an alarm, via the network, signals the condition to the competent operator.
Another example is the connection with the door contact sensors, which signals an abnormal opening of the cabin.


The TPU system allows you to keep the environmental conditions of the electrical cabin under control. It communicates remotely with the recovery systems and monitors the effects of their intervention, transmits signals and information to the operator using an Ethernet network port, reducing its interventions to the minimum necessary.
In this way it not only facilitates and reduces the work of the operator, but also guarantees a better and longer life of the transformer, avoiding blockages and replacements.

Contact us for more information!