As the experience of the operation and repair of electric motors shows, in most cases these units fail at the time of launch or inhibition, when a significant current flows through the windings, the value of which often goes beyond permissible limits.
But not only electrical windings suffer. The mechanical parts of the nodes are also broken, experiencing a dynamic blow at the start. That’s why it is so important to start engines without jerks.
Previously, this problem was solved quite simply. In the circuit of the windings included additional adjustable resistances of high power. Thus, the working current of course decreased, and with it the speed of rotation of the shaft decreased and the speed of rotation. But the whole trouble is that significant thermal energy was released on the resistors and, with intensive use, they quickly burned out. In addition, the moment fell on the shaft, and the electric motor could not crank the mechanism attached to it. In engines equipped with a frequency electric drive, these problems are fully resolved. But the whole point is that the servo is a rather complicated and expensive device and its mass use is very costly. That is why specialized devices for smooth launch have gained popularity, which in comparison with drives are quite simple and inexpensive. At the same time, they fully cope with their functions.
For example, ELT smooth starting devices meet all the requirements for this kind of electrical engineering. They are simple, reliable and recommended for use in various operating conditions.
In them, in addition to using the resistors already known to us, functions such as:
adaptive acceleration control;
adaptive control control;
Start with current limitation;
start with a smooth increase in power;
two sets of parameters;
impulse start;
low speed;
stop with linear voltage reduction;
Razgage slowdown;
braking by connecting direct current to 3 phases;
Smooth braking.
The headache of the heads of many enterprises who do not have their repair base are forced long downtime and losses associated with this. Therefore, they should not forget about various protection devices, without which the cost of rewinding of engines and repair of gears, bearings, shafts and other things can fly into a penny. Therefore, the use of such protective devices is a good choice.