MAYNUOM9811 Programmable LED DC Electronic Load 0-150V 0-30A 200W

I had purchased and returned a Rigol electronic load because I found it wouldn't work at less than 10ma. Puchased the Maynuo after consulting with users on eevblog. I was a little reluctant to purchase as Maynuo is not a mainstream brand in the US. I am so glad I did, the electronic load has great specs and lives up to them, even at loads under 1ma. The load is compact and quiet with an easy user interface. Haven't tried the software interface yet (it requires a special usb to TTL cable) and the manual is poorly translated from Chinese but you'll figure it out. Kuodos to the seller for getting the unit to me in 3 business days! Came with a US style plug but make sure you change the voltage switch on the back of the unit to 110 if you live in the US.

This e-load is an affordable alternative to the big name instruments. It's accurate and has good features to include pc connectivity. In regards to the latter, be careful though - the special Maynuo optically coupled comm cable is required for proper (and safe) operation w the free software which is downloadable from their website. The only drawback i've noted so far is the non-intuative programming routine. Also, if I waited another couple weeks, the 300 watt version would have been available for a little more cash.

From a functional perspective, this unit works well. However, I came across an issue in the modbus register assignments where the CMD register (the register used to confirm a command) overlaps the IFIX register (the register used to insert the current setpoint). The CMD register is supposed to be a single word long, however it is actually a word swapped long. Extensive testing shows that the unit will respond properly to either the current setpoint or the confirm command, however writing to the CMD will zero the current and writing to the current will send a error eo the CMD.The unit is fine in local front panel operation but not for modbus communications. Be aware that the communications are TTL and require a TTL to RS485 converter cable.

Works well. Did not come with USB cable, however. Still, seems to be a good deal so far.