System Size vs Operating power ?

Couple of newbie questions

I just had my solar system installed. It is a small 3.8KW system, with NET metering.

The annual production of the system is estimated to 6400kWh which should approximately match my usage.

I noticed a couple of things:

1. On the placard it says ‘Operating Voltage 240V, Operating current 12.1A’.
2. On the meter I see it ‘pushing’ 1.2 kW out when nothing is turned on in the house.

So, if the system is a 3.8KW system, why is the operating power only 2.9KW (240 * 12.1) ?

For the ‘pushing out’, obviously I need to wait and see over time, (and check the monitoring and my electric bill), but should I not see close to the ‘nominal’ power generation being pushed when checking around noon ?