Maynuo M9812 Programmable LED DC Electronic Load

We have now purchased a Maynuo M9812 Programmable LED DC Electronic Load rated at 0-150V 0-30A 300W.

We had planned to buy a DC load to use for testing battery drain, battery controllers and for our new solar data logger system which is slowly progressing. We looked at a very similar DC load from B&K Precision, model 8500 but this was over £1100 from UK suppliers compared to the cost of the Maynuo M9812 unit which was £304 plus import costs of £80.

After looking at the specifications and online reviews and video teardowns of both units we decided to order the cheaper model.

There is an optional TTL-USB isolated adapter available for around £80 but we have designed our own to fit into a DB9 plug on the back of the unit which will give us a USB com port to allow us to control and log software which Maynuo provide as shown below:

Click to view large image of Software Screen Shot
Click to expand

The DC load has a very useful function for battery testing which allows us to set a preset current draw and the load will consume this until the battery voltage drops to a preset level.

DC Load Features

  • Six high-speed operation modes: CC,CR,CV,CW,CC+CV,CR+CV
  • Over current, over voltage, over power, over heating and polarity reversal protection 
  •  High-luminance vacuum fluorescent display (VFD) screen with two lines, four-channel display
  • Intelligent fan system will automatically activate based on changing ambient temperatures
  • Soft-start time setting, activating the power supply in accordance with the set voltage value 
  • Battery test and short-circuit test functions
  • Capable of rising edge and falling edge dynamic testing
  • Supporting external triggers on either input or output
  • External current waveform monitor terminal output terminal
  • Supports remote voltage compensation and multi-data storage
  • Power-on-self-test, software calibration and standard rack-mountable
  • LED mode for LED power driver test, steady reading, compatible with simulating the capacitances sensitive driver
  • Edits arbitrary waveforms in the list function
  • Available with RS232/RS485/USB serial interfaces.

Manufacturers web page: