Places of Practice

When it comes to the environment, where the electric motor will operate, it is necessary to take into account some important factors. The main purpose of the operating temperature is to accurately specify the rated temperature or the temperature range at which the engine is designed to operate. Just before an engine starts its operation, its windings should be at the surrounding air temperature, also called ambient temperature. The temperature in the engine may become higher as soon as it is activated.

The combination of ambient temperature and engine baldor CM3107 temperature rise at a nominal load is the same as the maximum winding temperature in the engine. Thus, operating a machine in environments with the highest rated temperature may allow a reduction in the continuous torque of the motor at the same time as it operates in low temperature environments and may require another form of lubrication for the bearings.

The American National Association Manufacturers Association classified the insulation classes to meet all temperature requirements of electric motors, with insulation classes A, B, F, and H.

Association of open and closed contacts

Two types of association can be found, the association in series and the association in parallel. When it comes to the association of contacts, it is common to produce a detailed table containing all viable combinations between the contacts, called the Truth Table.

It can be observed that in the serial combination, the load can only be activated when these two contacts are activated and is known as the E function. In the parallel combination, any of the activated contacts activates the load and is called OR function.

acme TB81329

In the association of normally closed contacts, the NF contacts can likewise be found in series and parallel. In the same way, the parallel association is called the non-E function. Thus, in the same way to change a wheel in a car that is punctured, it is necessary to know in detail the appropriate tools and their electrical commands, to understand the operation of a circuit , Knowing the appropriate elements.

The main difference is in the fact that in large panels there are buses with great capacity, which can expose people to situations of possible risks.

Some Transformer Losses

When considering real transformers, the losses resulting from their operation must be included in the calculations. The losses are demonstrated in “power flows”, which make the output power of the transformer different from the input power.

Basically, there are four major loss types in power transformers:

  1. Copper loss: it happens by the Joule effect that occurs in the conductors of the transformer windings when traversed by the electric current.
  2. Foucault currents: also known as parasitic currents. These currents circulate inside the transformer core when it is subjected to a time-varying flow, causing losses by Joule effect.
  4. Loss by hysteresis: associated with the reorganization of the magnetic moments of the ferromagnetic material that is made the core of the transformer. Each time the hysteresis cycle is traversed, a portion of energy is expended for these magnetic moments to be realigned. To reduce this type of loss, we use materials with appropriate ferromagnetic characteristics.
  5. Dispersion flow: magnetic fluxes that emend with only one winding and whose trajectories are defined mainly through the air are denominated dispersion flow. These fluxes translate into a proper inductance for both coils.