What type of engine do I have

[Juan]

Hello everybody!

I would like to clarify that my level of English is very poor, and to write in this forum I am using a Spanish-English translator, although I can read much better than I write...
Having said that, let me move on to the question
I have bought a mini circular table saw and I would like to regulate the saw's rotation speed (rpm).
I only have some very basic knowledge of electricity and electronics and it is not enough to dispel my doubts about the use of a voltage regulator as I am faced with a type of motor I do not know....
The only information about the motor comes from the seller who says that the motor is 220v 1200w and 10000rpm. No indication on the motor itself.
But you can see that it is a brushed motor and that it has 4 diodes (10A10 1000V 10A General Purpose Rectifier) which apparently are connected in series.
I bought a Chinese voltage regulator SRC 220v 2000w 25A, then I tested it for a few minutes on the motor with success. Although I didn't measure the speed because I don't have a tachometer.
The first question is: what type of motor is it?
Other questions:
in the case of daily use
1. Adjusting the voltage of a motor of this type can damage it?
2. Does it decrease the performance of the circular saw (e.g. torque, speed, etc.)?
3. Is the Chinese regulator I bought sufficient for the task?
Could one of you clear up the doubts that I have?

Thank you very much

 

[Bluejets]

Cannot say what the "speed regulator" is, whethere suitable of not simply from a photo.
Perhaps a link to where to bought it might shed some more light on that.

Motor would be a series motor.

I do not see the need to lower the speed of a table saw.
You would be constantly shifting the speed to handle your varying loads and run the risk of cooking either the motor or any speed control unit or both.

 

[Juan]

Thanks Bluejets,
This table saw is "Multifunctional", I can use it for drilling or polishing, for example. This is why I want to control the motor speed.
But, If you are telling me that it can be a risk for the motor / regulator it is better to give up the idea.
Regarding the Chinese voltage regulator, I can't remember where I bought it, but at the time I copied the characteristics of the regulator, here's an attached rtf file. Maybe there is another method that I don't know about?
Thank you very much for your quickly response to my question.

 

[bidrohini]

1. 1)Controlling the voltage supplied to an AC brushed motor can affect its speed and torque. However, you need to be careful when doing this, as reducing the voltage too much may lead to the motor not having enough power to function properly or stall under load. On the other hand, increasing the voltage beyond the motor's rated voltage could lead to overheating and damage. If you are within reasonable limits and don't push the motor beyond its capabilities, it should be fine.
2. 2) Adjusting the voltage will affect the motor's speed and torque. Reducing the voltage will reduce the motor's speed and torque, which might lead to decreased cutting performance. However, it may also help you achieve finer control for certain materials or cuts. Increasing the voltage could lead to higher speeds and more cutting power, but be cautious not to exceed the motor's capabilities.
3. 3)The Chinese voltage regulator you purchased is rated for 220V input and 2000W output, which should be sufficient for your 220V 1200W motor. The 25A rating means it can handle up to 25 amps of current, which should be enough for your motor's needs. However, be sure to check the specifications of the motor to ensure you are not exceeding its current or voltage requirements.

 

[Juan]

Thank you very much bidrohini,

It would be important for me to be able to regulate the speed of the motor because it allows me to significantly expand the use I can make of it.

 

[Bluejets]

On the other hand, increasing the voltage beyond the motor's rated voltage could lead to overheating and damage.

Not possible to increase beyond the supply voltage via the regulator, a ridiculous statement.
Series motor would be speed regulated via thyristor (phase) control but as you would be relying solely on the back emf to give any kind of feedback, the motor speed will hunt up and down as load changes and would be a nightmare trying to deliver constant.
There are specifically made systems which monitor field and armature current and adjust accordingly to a set parameter but beyond the scope of the device at hand.
Better just to leave as is.

 

[debe]

Some front load washing machines here in Australia have brush style motors that vary there speed. There speed is controlled by a tacho generator mounted on the back of the shaft fed to the controller. Thats one way of having speed stability with varying loads.

 

[Juan]

With all due respect, I think that the differences of opinion in the answers to my question are most likely due to a lack of information about the engine characteristics.
The remaining option is to disassemble the engine, but as I am not an expert on the subject, I am afraid of damaging it.
I will leave the problem on stand by for now.
Anyway, I thank you all for the interest and passion you have shown in your replies.

 

[Bluejets]

With all due respect, I think that the differences of opinion in the answers to my question are most likely due to a lack of information about the engine characteristics.
The remaining option is to disassemble the engine, but as I am not an expert on the subject, I am afraid of damaging it.

No, it's your lack of knowledge on the subject as there are variables in the answers which are correct.

Good idea not to disassemble as it would not tell you anything that we don't already know ...and yes, more than likely you will damage it.

 

[Juan]

Thanks again, Bluejets...
You are right, unfortunately I know nothing about engines, and that's the main problem....

 

[sgodblacktechy]

It's great that you tested it and it worked well, but consider using a tachometer to measure the speed for better accuracy.

 

[Juan]

Thanks sgodblacktechy, Thank you all for your help.