Description
Specifications:
- Main Board
- Complete Arduino compatible board with ATMega328P-AU (Arduino Duemilanove with ATMega328)
- 8×2 LCD white character with blue back light & adjustable contrast
- On board USB-serial port through USB micro connector
- 1 2×6 edge card expansion slot for input card
- 1 SPI port
- 1 I2C port
- 2 analog input pins
- 1 digital IO pin (external interrupt capable)
- 1 external analog voltage reference pin
- 5V and GND pins
- 1 2×6 edge card expansion slot for output card
- 1 SPI port
- 1 I2C port
- 3 digital IO pins (1 external interrupt capable)
- 1 input voltage pin
- 5V and GND pins
- 4 push button
- 1 red LED for power indication
- 1 yellow LED for system status and operation
- 1 green LED for USB activity status
- 1 buzzer with transistor for loud and annoying sound
- 1 reset button
- Analog reference voltage with LC filter
- Auto reset selection through jumper
- 6 – 17 VDC input range for power
- Auto power source selection (USB or external DC)
- 6-pin AVR In-circuit serial programming (ICSP) header
- Can be slotted into 1/16 DIN panel cutouts
- Input Card
- 1 thermocouple type K input port:
- Temperature measurement range: -200°C to +1350°C
- Resolution: 0.25 °C
- Cold junction temperature measurement
- Based on MAX31855KASA+ chip
- Thermocouple open and short (ground and supply) detection
- 1 thermistor input port:
- External thermistor reference resistor port
- Thermistor nominal value and coefficient set through front end software
- 1 thermocouple type K input port:
- Output Card
- 2 SPST-NO relay 10A 250 VAC (only 1 mounted)
- 2 Oz copper PCB
- 1 transistor output pin to drive external SSR with DC control input
- 1 red and 1 green LED for relay on indication
- 1 yellow LED for SSR on indication
- 1 selection jumper to choose either on-board relay or external SSR
- Enclosure
- Laser cut enclosure
- Made from transparent acrylic material
Open source hardware is all about sharing:
- Check out osPID website for complete information
Francesco –
In my opinion this is a very cool project!
As an educator in Measurement Science I see it as one of the better choices to teach measurement and feedback control theories topics in many experimental laboratory classes.
I can’t wait to have my first osPID to experiment by myself and to give it to my students and see what they will be able to do with it!
Francesco – Italy
Mikkel –
I started out trying to build the “Poor Man’s Reflow Oven” (http://spectrum.ieee.org/geek-life/hands-on/the-poor-mans-solder-reflow-oven) with the Auber Instrument’s PID he mentions in the article. I was very unhappy and had many problems. The applet that ships with this that allows control from your PC is a GAME CHANGER. Graphical display of the temps/set points, control the unit from the PC… I could have saved myself so much frustration if I had only gone with my gut and gone OSHW from the start!
Jon Lambert –
Have you given any thought to modifying the available analog input to accept 4-20mA, 1-5V or other standard analog signal ranges? It seems this would be fairly simple given the current controller accepts a type “K” millivoltage input. Also, providing an analog output of 4-20mA would be hugely beneficial for those of us teaching PID control and employing traditional industrial components in our lab experiments. Thanks – JL
Administrator –
Hi Jon,
We have plans for that & some initial design was made but still struggling to find the time to come up with something solid for public release.