Our PV system has been playing up a bit, the Mercedes Benz battery not always wanting to let us have access to the stored 10kWh. There doesn't seem to be any logical pattern to what causes the problem but we have known that a software update which is available could possibly solve it.
MB are still in the early days of their Home Energy business and seem still to be a bit cautious. They don't yet have the means to remotely access the battery nor indeed to monitor the system. I part this is for sensible safety reasons, their thought being that anyone hacking in to the system could monitor ones "habits" and therby work out when the house is empty.
Indirectly they can get some information with the manufacturer of our inverters but it's not adequate for a full detailed check.
So Stefan had contacted them and arranged for a service person to come by and update the software and check all was OK. As there are only a few (four) support people for telephone and on site service and support, it meant an engineer based in Kamenz near Dresden in Saxony having to make the 600km one way trip to us. He had driven down yesterday, stayed in a nearby hotel and arrived this morning.
Software was updated and everything analysed and checked through and seemed to be OK. He went through quite a few tips and tricks for our electrician Stefan which helped him to understand more about how the system worked and got to learn how to access certain testing facilities not shown in the handbooks, so that was very useful.
However as bags were about to be packed up, I suggested we switch on a major electrical energy user (our hydraulic 400V garden gate) and bingo the battery shut itself down. Puzzled looks. Notebooks started up and diagnosis software restarted. The engineer was sure the 4 x 2.5kWh batteries were 100% in order and so the search moved down to the interface with the second PV inverter which transforms excess 230V AC energy from the first inverter (which transforms the PV panel DC energy in to 230V AC), back in to DC for the battery and when required at night, the stored battery energy back to 230V AC for our light bulbs.
And there unexpectedly the problem was found, shown by a minimal difference in voltage between the systems when there was a sudden large power usage. However this minimal difference was enough for the safety systems to give the "shut-down" command. And then the offending piece of hardware was quickly found - a very slightly loose screw holding a wire in the inverter. Once tightened everything worked perfectly!
So a lesson learnt by all but a useful though costly one for MB (the two day 1200km round trip) and if you like for us in that we had to purchase electricity at night rather than use the stored battery energy,.
However this kind of thing doesn't bother me so long as those responsible work on getting it sorted and in our case there can be no doubt that tis is the case with our electrician Stefan nor indeed fom the MB support staff who from the very start were incredibly helpful and patient on the phone when the system was first installed.
This is new technology and from today's standpoint, is one of the cogs in the wheel that could help us to do something positive towards slowing down the clear problems caused by climate change.
Interestingly MB has just announced it is pulling out of the German Sports Car Championship (DTM) and moving in to the Formula E, electric car racing series. Could Formula 1 follow? I personally would greet such a move if it meant the millions spent there largely for the benefit of a very few, would be better used finding a solution to the diesel engine problems and help all those thousands or millions of people who were told they were doing something positive for the environment by buying diesel vehicles.
Just for anyone concerned about the lack of MB field support staff - they are about to roll out a programme to recruit local regional support staff.