I have just taken delivery of a brand new EB3A - bought from a reputable third party supplier here in South Africa. On installing and charging up the system all the outputs seem to work. AC Power via the Inverter and SA Three Pin Plug. Both the USB-A and the USB-C sockets also check out fine. However the 12V DC output is not fully operational. The “Cigarette Lighter” output works with the DC Power on and gives a steady consistent output which I can measure at 12.9 - 13.0V. 12V devices work via connecting a Cigarette Lighter to 5.5mm plug cable. However the two individual DC5521 sockets have no output power at all when DC is switched ON. Either measured at the sockets or via a cable-connected load. I have tried several different cables, connected to different devices (all which are OK when used in 12V sockets on my main Inverter trolly - 2kVA battery), which I have been using for over one year and I can cross-check that cables and devices are working. When I connect a load, which should be 17W, to either of the DC5521 ports on the EB3A - with DC power switched ON and showing on the display - the output is ZERO watts. When I connect this same load (a 12V DC Monitor) to the 12V DC “Cigarette Lighter” socket on the EB3A it displays “DC” the same but this output works, shows 17Watt Output and the monitor works perfectly. So the 12V DC output supply is working correctly but seems it is not corrected correctly to the DC5521 output sockets.
Before retuning the unit to the supplier is there anything stupid I am not doing??
Probably I’m doing something stupid testing it like that 
, but I suppose the sparks mean it’s live. Not touching it again like that for sure 
.