Question: How Do You Slow Down A 12V Fan?

Can you slow down an electric motor?

Slowing down a single phase AC motor can be complicated and expensive.

They are usually built to be run at a certain speed and anything else would be tricking it to do something it wasn’t meant to.

Simply slowing it down may cause it to overheat with reduced mechanical self-cooling..

Why do computer fans have 3 wires?

The third wire gives your computer a measure of control over that. It reports the speed of the fan back to the computer’s processors, which allows the motherboard to control the speed of the fan by raising the voltage – and speeding the fan – when the extra cooling is required, and lowering it when it’s not needed.

How many amps does a 12V fan use?

2 ampsAt 12 volt the fan will draw 2 amps of the 8 available from.

How can you make a DC motor spin slower?

A couple of things you can do:Use gears to change ratio of speed, which is what you’re going to do. … Use a stepper motor, which are commonly used for high-torque, low RPM applications.Find some sort of PWM control circuit to slow it down, although you probably won’t be able to get it down to 5-10RPM.

How do you power a 12V DC fan?

To power a DC fan, we feed the fan its rated voltage. For example, to power a 12VDC fan, we need to feed it 12 volts DC. This power can come from any DC voltage source, such as a DC power supply or even batteries. If using batteries, in order to get 12V output, you would have to place 8 ‘AA’ batteries in series.

Do fans have resistance?

A fan isn’t a passive device; you can’t expect to measure its resistance and get a meaningful value, because its voltage/current curve is nonlinear. More than that, it will vary depending on external conditions, such as backpressure and whether or not something’s blocking the fan blades.

How do I get 7V from 12V?

You can achieve that by inserting a 6Ω resistor in series with the 12v supply. The circuit being powered forms the ‘lower’ end of the voltage divider. 1A through 6Ω is 6v, so you have achieved the final voltage of 6v. But the 6Ω resistor is now dissipating 6W, which is a substantial amount of wasted power.

How do you slow down an AC motor?

Most DC motors can be slowed down by reducing the supply level of power, Volts, lower volts and resulting less amps, will create less electrical field and will slow motor down. For more gradual speed control there are electronic solutions that are called PWM (Pulse Width Modulation) controllers or Mosfet H bridges.

How do I slow down my fan speed?

With a Shaded Pole motor, you can simply reduce the voltage, say with a light dimmer and the motor produces less torque, then with less torque the air friction on the fan blades causes it to slow down, which in turn moves less air.

How do you control the speed of a DC fan?

If you want to vary the speed of DC fans, the only option is to vary the input DC supply. The DC power supply can be reduced below 12 V for lower speeds. There are still limitations in the percentage decrease in the speed of DC fans.

Can you bypass a blower motor resistor?

In the highest speed state, the blower resistor is bypassed completely and the fan is connected directly to the car’s battery, which allows maximum current through the motor. … Power to the blower motor is fed through the blower motor resistor, so if it fails or has any issues power can be cut off to the motor.

Can you slow down a ceiling fan?

You can add a resistor, a capacitor or an inductor in series with fan permanently. This will increase overall impedance and reduce the current, thus reducing the fan speed. Another possibility is to change the capacitor in auxiliary winding from 2.25 mfd to say 1.85 or 2 mfd. This will reduce fan speed.

How long can a DC motor run continuously?

You should anticipate, given proper attendance, that the motor can run continuously for the life of its brushes, which should be in the range of six months to a year. Presuming that the motor is too small to have its brushes changed by a trained electrician while running.

How can I reduce the speed of a 12v DC motor?

Thus, the speed of a DC motor can be controlled in three ways:By varying the supply voltage.By varying the flux, and by varying the current through the field winding.By varying the armature voltage, and by varying the armature resistance.

Can you use a 120v switch for 12V?

Yes, you can use a 120v switch for a 12v application. The 120v is the max voltage rating of the switch, which states that it can handle voltages up to 120 volts.

How do I control my 12V DC fan speed?

Just place a resistor in series with it or use a pot. The maximum current is only 104 mA with an average of 90 ma. It will start as low as 4.5 volts so slowing it down is not difficult. Start with about a 120 Ohm 2 Watt resistor or get a 100 Ohm 2 watt pot and find a speed you like.

What resistor do I need for 12V fan?

You have a 12V @ 10A = 120 W power supply. If the fan becomes a short circuit, it will pull all 10 A. In this case, you would need a 120 W resistor to “protect” the fan.

Is PWM or DC better?

PWM fans are useful because they minimize noise output and are more energy efficient than DC fans. Due to how they function, the bearings in a PWM fan will last much longer.

Is PWM fan better?

3 pins fans can still be regulated via voltage regulation. Given that fans are 12V, if you feed it 6V it will spin at half speed, etc…. You can actually still regulate fan speed on 4 pin fans this way as well. However, PWM is preferred as it’s more precise and easier.

How do I convert 12V to 120v?

You have to first convert the 12 volt DC power to 12 volt AC power, and then run the 12 volt AC through a step up transformer. Commercial power inverters and converters supply 120 volt AC power from a 12 volt DC source such as a car battery or solar panel.