cheapest [feasible] ebay inverter put to the test

[gnubie]

Thought some people might find this interesting. In part 2 a dehumidifier gives a good demonstration of just how much current a conventional AC motor compressor draws at start up.

 

[upnorthandpersonal]

Modified sine wave and AC motors or inductive loads in general are definitely not a good match to begin with either, so I'm actually very impressed it managed to start it and all the other loads he attached (and combinations).

 

[gnubie]

Yeah, I was surprised by that too. Normally the transistors let rip due to over current or voltage spikes from the load since they are directly connected to the load rather than via a nice inductor as per pure sine. A lot of these things do overload sensing by watching what the HVDC supplies are doing, ie if their PWM is wide open assume over current, if their output voltage is low assume over current.

This one has good tight regulation of the HVDC, suprising in itself, and it uses a shunt to sense the load. That's quite unusual to see at this price point.

 

[upnorthandpersonal]

Really makes me want to get one of their pure sine wave inverters and see how it holds up. Their 5kW/48V/240V one is less than $300.