Solar pv... how does the diverter work?

I think Solar PV is the way to go, you can use the energy in many ways and possibly get paid for excess one day in this little land.....!!
The Diverter is wired into your immersion circuit. You drop the temp to 60oC and leave it set to bath and ON permanently. Then, in my case with an Eddi diverter, when there is excess and my battery is full, it dumps to the immersion coil and heats the water. Any excess above or after this is exported. If the panels aren't producing any excess or it's taking forever to fill up your battery on a dull day, you'll never see any diversion to the immersion. My Eddi shows me a daily quantity of power diverted to the immersion in kWH which is reset each day. Once the tank reaches 60oC is states Max Temp Reached and that's it until it cools down or someone draws off some hot water somewhere....and we're off to the races again!
I turned off my gas a few weeks ago and use a scheduled boost timer on the Eddi to heat my hot water twice daily. I've off peak rates so this plays into my hands for the morning boost at least and if we get any decent sunshine the tank is kept nice and hot during the day!
There is a manual boost on the Eddi also if you need more hot water for some reason and you can always run your boiler if you wish.
Sometimes you can find the diverter draws power against your PV Battery which isn't really what it's supposed to do. I've seen both scenarios but worth asking how it behaves, you want to keep the battery for house load not waste it hot water if you can help it.