admin » 22 янв 2017, 15:56
Universal single-phase motors can be found in many household appliances (washing machines, clothes dryers, etc.). They can be operated by direct or alternating current, and also have tachometer for determining the speed of rotation
These motors have no fixed rotational speed, so they need a control circuit.
In simple cases, and under constant load, it is sufficient to use a dimmer. With him will work, too. However, the rotation speed decreases with increasing load. For example, for use in controlling the lathe a simple phase control is thus not suitable. In order to remain at a constant rotation speed is necessary to use a different scheme.
Universal speed controller TDA1085C Motorola, designed specifically for the use of these motors in washing machines. This scheme is essentially taken directly from the datasheet on this chip.
Note: TDA1085 are no longer produced.
Note: The entire circuit is not isolated from the mains! The relevant safety regulations must be observed. I do not bear any responsibility for any damage or injury!
Information: R16 constantly consumes about 3W and heated respectively quite.
300-500W power engines. Triac should be used with a supply current of 3-4.
For the calculation approach 1 kilowatt at 220V = 5 amps of current.
Triac is targeted at 12 and it is about 2kW. Without headroom.
However, the track of the scheme on such a large current is calculated.
For use with high-power motors it is necessary to strengthen the track conductor.
Or make a triac in a separate cooler.
Also I recommend to replace the triac BTA41.
To control a powerful hand tool with a commutator motor without a tachometer, there are other control schemes. (In development)