Supervising the ventilation of an electrical panel is a fundamental step for the life of the components housed inside it. As we have already seen in the previous article, a lot of attention must be paid to the design of adequate ventilation as to ensure proper operation of the electrical and electronic equipment.
Forced ventilation in electrical panels
The increasing use of processors with high computing capacity (to meet the needs of big data transfer, image processing and real-time control of devices, i.e.) develops heat due to the localized Joule effect, the disposal of which has become incompatible with only natural dissipation techniques.
Forced ventilation therefore becomes the temperature management solution with the best price / performance ratio, of simple sizing and maintenance, but we want to pay attention to its supervision, which will allow us to intervene in the detection of potential anomalies, promptly report alarms, or produce predictive maintenance information to employees.
First of all, to supervise the ventilation of an electrical panel, it’s necessary to distinguish the equipment with an integrated control panel from that controlled by a cabinet on the machine.
Supervise ventilation on integrated control panels
The integrated control panels provide architectures based on Single Board Computer or dedicated cards, with a tunnel or cooling paths designed ad hoc. For this type of applications, the use of DC fans is preferred, which have a feedback signal on the rotation obtained directly from the torque and speed control of the fan itself. Fandis offers models that provide the output signal from the fan in two types, as indicated in the figures.
The designer can therefore choose whether to arrange the signal in frequency, proportional to the rotation speed, or whether to keep it level, through a monostable stage and immediately usable as an alarm signal.
The signal is always open collector, usable by the electronic control boards without conditioning and therefore without additional costs.
Supervise the ventilation on panels on board the machine
In the cabinets on the machine, on the other hand, we have modular systems composed of different elements such as IPC, PLC, drives, I/O modules, all mounted in a cabinet on a DIN bar. In this type of electrical panel, the main cause of ventilation inefficiency is due to filter pollution and not to fan anomalies. Sometimes, systems are updated with revamping operations, replacing some modules to obtain new functionality or performance. For this type of applications, the use of a signal feedback from the fan is almost unusable and in many cases unsuitable for detecting anomalies. In fact, we could have a fan that rotates perfectly, but an altered air flow from an open door or a clogged filter.
For these applications, Fandis’ solution is Sensis, a unique product that can be easily used both on new projects and in the revamping of existing enclosures, able to manage climate control and supervise ventilation efficiency through an air speed sensor.