02 October 2014
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3
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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 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: www.maynuo.eu
Front Panel with case removed
Nechry
Always happy with your M9812 ? I hesitate with a Itech IT8512A+ and this one
Brian
I haven't had any issues with the M9812, we have used it a lot to measure battery capacity and when testing power supplies under load.
Nechry
Thank, I think I will order one, but the previous version the M9712, I'm not sure if I really need the LED test mode. As I understand is the only difference.
Diego Mariani
Buongiorno, come si collega al pc? C'è un software che permette il collegamento? Ho visto che ha un ingresso sul retro TRQ e TRI, come le posso utilizzare? Quali tensioni si possono applicare?
Good morning, how do you connect to the PC? Is there software that allows the connection? I saw that it has a TRQ and TRI input on the back, how can I use them? What voltages can be applied?
Brian
Hi, the load connects to the PC via a serial connection. The blog post at https://www.briandorey.com/post/maynuo-m9812-serial-to-usb-adapter shows a circuit we made.