Today we’ll make the simplest soft start for 220/380V with our own hands and save a lot of money!
The idea for the video was born thanks to the AEROMAX B2105T compressor head from FOXWELD
☑ - Compressor head AEROMAX B2105T - foxweld.ru/products/item/komp...
☑ - Manual soft start scheme + automatic version - 1000ss.ru/146-plavnyy-pusk-38...
Which has already arrived and in the next video I will assemble a powerful compressor.
But AEROMAX B2105T requires an engine with a power of at least 7.5 kW. And if your power line is weak and such a powerful compressor cannot handle it, then there are two options. Or reduce the driven pulley, which will reduce productivity. Or make a soft start. Some may have to do both.
So. A soft start for an engine with a power of say 7.5 kW costs twenty, or even thirty thousand Russian rubles. Today I will show you how to make a manual soft start and an automatic soft start for a three-phase motor. A soft start can help not only on weak power lines, but also when the engine is under load and the belts break during startup.
How to make the simplest soft start for 220/380V and save a lot of money? To make a soft start, you need to buy or make three resistors yourself.
My resistor sizes are as follows. Nichrome thread 3mm thick. The insulator width is 94mm, thickness is 18mm, and 50 turns are wound. On one insulator we get a little less than 12 meters of nichrome, multiply by 3. And in total we get 36 meters of wire. I think the wire cross-section would be enough to be 1.5 -2mm.
The insulator can be made from asbestos pipe, fire bricks, porcelain and ceramic products, and even mica plates. I would most likely use heating elements from faulty hair dryers as insulators.
For a manual soft start, in addition to 3 resistors, you will also need two three-phase 16 ampere circuit breakers. For an automatic soft start, you will need the same resistors, one three-phase 16A circuit breaker, one contactor with a 220V coil and one KN102Zh dinistor. You'll get a cool soft starter.
In the video I showed how to make an automatic soft start and how to make a manual soft start from the simplest materials and parts. After which we conducted a series of interesting tests.
Which showed that a homemade soft start works no worse than factory ones.
At the end of the video I made another manual soft start for 220 V electric motors.
Now you know how to make the simplest soft start for 220/380V and how we save a lot of money.