I decided it would be easiter to explain AC and DC current if the user already knew how to use and oscilloscope. Explaining how to use an oscilloscope is easy if the user already knows what DC and AC current is. I think the video worked out as a fast paced tutorial for both subjects.
AC vs DC Explained and How to Use an Oscilloscope – [Link]
Microcontrollers usually don’t have specific ports for measuring currents, but they do have ADC channels through which you can measure analog voltages of a certain range. This means a dc current can be indirectly measured by a microcontroller’s ADC channel by first converting the current into voltage. The simplest way of doing this is to place a resistance in series with the current path and measure the voltage drop across it. But hold on, if you place an additional resistance in the circuit, it will affect the original current. Therefore, we need to use a very small value resistance so that it’s effect in the circuit current won’t be significant.
How to measure dc current with a microcontroller? – [Link]
This is a nice example of scavenging parts from an inkjet printer to make cool stuff. It uses an Arduino and a Motor Shield to control the DC motor. The web site has a lot more information and the source code to get you started. [via]
Using a DC motor as a servo with PID control – [Link]
It may be used in many receiver configurations: as a simple DC receiver, binaural receiver, phasing receiver, etc. It’s ideal for use with a DSP system. Since the TUF-1 mixer is specified up to 500 MHz, the module will be suitable for 70 cm. By swapping over the RF and IF connections to the mixer (a couple of track cuts and two pieces of wire), LF and VLF reception is feasible.
DC RX Module – [Link]
This kit combines an LM317 with a thumbwheel potentiometer to allow you to easily set the output voltage from 1.5V up to 2V less than the input. Three preset voltages (5, 9, 12V) can also be selected. Input power comes from an external source.
- Stable, low-noise output adjustable from 1.5 to 30V
- Supplies up to 500mA
- Preset outputs of 5V/9V/12V
- Integrated heatsink
A general purpose dc power supply KIT - [Link]
This is the circuit which inputs the control voltage which was created by the turning of the motor in PIC. The input voltage to PIC is converted by A/D converter. Changed voltage is used for the PWM function of the CCP to control the motor drive. At the circuit this time, a small motor is used as the generator to detect the number of rotations of the motor. The input voltage (the control voltage) to PIC is changed by the fluctuation of the number of rotations of the motor. [via]
DC motor speed controller - [Link]
Previously we explored DC motor control using the LMD18245. Now, looking forward we’ll use a method for even better motor control using the infamous L298. Specifically the L298HN (makes things even easier), Check It Out!
L298 DC Motor Control - [Link]
This is a nice LCD panel addon for you power supply. It displays voltage, current, peak current, power measure, energy calculation in kWh or Ah, operation time, bargraph display, temperature and more! This project is published on Elektor January 2008 magazine.
- Voltage V (0 – 30V), a standard feature at 13.8 V
- Electricity in A, Optional max. 5A oder 50A (JP1) 5A and 50A (JP1)
- Peak electricity without display unit
- Performance in W (1 – 999W)
- Electrical work in kWh
- Ah capacity battery for operation or for battery charge
- Duty in hours / minutes, after 1 week in days
- Temperature sensor Opt.
DC power supply-power meter module -[Link]
This is a dc power meter that will measure voltage, current and calculates the power output on a LCD display. It will also display peak current, kWh and it has a analog like bargraph. Design schematic is based on ATMEGA8 AVR uC.
- Voltage V (10 – 20V), a standard feature at 13.8 V
- Strom in A (0,1 – 50A) Electricity in A (0.1 – 50A)
- Spitzenstrom Peak power
- Leistung in W (1 – 999W) Performance in W (1 – 999W)
- elektrische Arbeit in kWh Electrical work in kWh
Shack DC-power meter (Power Analyzer) - [Link]