The CurrentRanger turns your multimeter or oscilloscope into a precise nano/micro/milli-amp measurement instrument.
It avoids the problem of burden voltage present in most DMMs and even some expensive bench multimeters.
It's really important that you understand how to use this instrument properly otherwise it can be damaged.
To keep cost low, there is no isolation between input, output and USB or any other header connectors.
Therefore it's crucial to understand how to use CurrentRanger properly, without creating ground loops and current paths from input to output or to USB, or it can be permanently damaged. In a nutshell, you should never have 2 earth ground referenced circuits connected in any combination to the CurrentRanger. Read the guide safety page for details and good/bad usage examples.
Please see the official guide that includes complete specifications and instructions for use!
- Fully digitally controlled by a SAMD21 Cortex M0+ ARM processor
- Programmable via Arduino IDE
- Touch pads for quick manual ranging and toggling of certain features
- LiPo battery powered extends battery life and measurement range
- Auto-power-off saves your battery after a period of inactivity
- Unidirectional/Bidirectional modes allow DC/AC measurements
- LowPassFilter feature allows smoothing scope traces for crisp detail
- Optional OLED display to show local readings without a DMM
- Optional Bluetooth/HC-06 serial module allows data logging to a PC
Default kit components (shown with low profile banana terminals & display options):
- CurrentRanger board
- 4X low profile banana terminals - these are really nice, compact and cost effective, highly recommended over the bulky "GOLD" terminals
- thumb terminal for easy input wiring (separate, requires soldering)
- buzzer for audible feedback (separate, requires soldering)
- optional SSD1306 0.96" I2C OLED Display with 1x4 female header (requires soldering)
- 3D printed box and mounting screws (box also available on Thingiverse)
- No battery is included, please see the guide for required LithiumPolymer battery specification
- Upon availability/request - "Gold" banana terminals (with 3D printed "half-moon" mount adapters)
Limited availability - plastic shielded GOLD terminals
You can now order these plastic shielded GOLD banana terminals.
Please see photos below of how they look and feel compared to the compact terminals.
Also see some examples and customizations in this forum thread.
CurrentRanger with the compact low profile banana terminals:
CurrentRanger with both the low profile and the shielded GOLD terminals:
Other connectors & customizations
The CurrentRanger was designed to allow many types of standard connectors, below are just a few examples. You may source your own custom connectors from ebay and other similar sites, to suit your needs.
Please see the CurrentRanger forum for discussions, customizations and common issues/solutions.
Sample capture of a radio packet:
Here's a sample capture of an RFM69 radio packet, shown here on an oscilliscope. This was captured in the mA range where 1mV == 1mA of current.
Andreas Spiess' review: