Tagged Questions

1
vote
2answers
62 views

simple h-bridge polarity reversal

I am trying to reverse the polarity on a rather beefy motor (5 amp, 60v) in the most simple way possible. I need to build an h-bridge just to reverse the current, I am controlling speed elsewhere. ...
1
vote
1answer
51 views

Detecting Motor Overload

I want to make a circuit to indicate an LED if a motor is drawing too much current. (when the motor is stopped for example mud got stuck around the gears) I am using 9-12 volts to power my motor, and ...
2
votes
3answers
1k views

Relationship between frequency and current

Hello I have a simple question, I was reading in my Airplane Maintence book that in AC motors are frequency sensitive (I understand that) frequency changes can cause speed changes of the armature. ...
1
vote
1answer
74 views

How do different kinds of motors behave electrically under operation?

This is sort of a follow-up to this topic: Overclocking my toothbrush I have since measured some numbers with my DMM. Remember this is a tiny brushed DC motor in a $5 toothbrush that I am driving ...
1
vote
2answers
227 views

Continuously Measure 3-Phase Motor Current

What methods are there for continuously monitoring the current in a 3-phase servo motor for a CNC machine and giving an alarm when the current is less than some value?
4
votes
4answers
348 views

Overclocking my toothbrush

I use these toothbrushes: http://www.amazon.com/Oral-B-Advanced-Toothbrush-Vibrating-Bristles/dp/B00336EUV8 They tend to run out of battery quite quickly. I'm happy to keep buying more because ...
0
votes
1answer
275 views

stepper motor current rating

I am having 8 wire stepper motor rated as 12V ,0.95A, and torque=1kg cm it has coil resistance 3 to 4 ohms. I have successfully run this motor with help of this forum. Now i have one doubt regarding ...
6
votes
3answers
392 views

What would be the difference in a coil of wire and just a cylinder of solid copper?

Ok so I am learning about induction and I always see coils of wire with no insulator. So I was wondering, What is the significance of it being a coil of wire rather than just a solid cylinder since ...
5
votes
1answer
224 views

Need help understanding and interpreting IGBT datasheets

When it comes to motor control, I understand that we have the option of using discrete MOSFETs or IGBTs. Also, there are some products in the market where 6 IGBTs are placed in one single package, ...