OverLoad V1.1 - Opensource Electronic Dummy Load Base on Arduino

OverLoad V1.1 - Opensource Electronic Dummy Load Base on Arduino


OverLoad is a oepn source electronic dummy load  which base on Arduino platform. It use the ATMega328P chip as main controller, and you can use the Foca to update the firmware by Arduino IDE.

Features
- 3A – 12V adjustable electronic dummy load, 10mA and 10mV resolution
- ±30V Voltmeter, 10mV resolution
- ±3A Ammeter, 30mV resolution
- Base on Arduino (ATMega328P) , hardware and software open source

It can be use as a electronic dummy load , a Voltmeter or an Ammeter.  Using the MENU Rotary encoder with button to select the funtion, and the Load Current Rotary Rheostat to change the constant value of current (it's invalid in Voltmenter and Ammeter mode).

In Dummy Load mode, it can work with 3A - 12V , and there is a 3A resettable fuse on board, it will protect the dummy load when the current more than 3A. In our aging test, we shot this fuse and change the circuit to let it work with 3.5A - 14.5V and it survived after the 3 hours test. Because we use the rotary rheostat to change the cunstant current valule, so there is no minimum resolution in theory - the rheostat will make the selection “continuous”. In measurement and display, the Dummy Load can reach the 10mV and 10mA accuracy.

In Voltage mode, we use the 12bit ADC so it can work with -30V to +30V input and reach the resolution at 10mV. In Ammeter mode, it can measure from -3A to +3A, resolution is 30mA.

Power supply for OverLoad should be 12V DC. And now we add the power switch for OverLoad so you don't need to unplug the power jack to turn it off anymore.

Buzzer and SD card is reserved, they will not be used in the firmware, but you can add these function yourself because it's all opensource and base on Arduino.

Specifications

Source Code (firmware)