Problem with Meanwell PB-1000-24 chargers

Dear friends,

I am living off-grid and use an array of 30 solar panels, 2 wind turbines and a 20KW 3-phase generator (for the "powerless days").  A few years ago,  I installed three MW PB-1000-24 switching chargers in order to charge my 1800AH battery bank from the generator. Inputs are connected each on one phase, while outputs are paralleled to the battery. All was fine for a few years, but yesterday all chargers indicate failure.  Their leds are red, like there is no detected battery. Of course, battery and connections are fine, I am currently running on the battery. The weird thing is that the exact same problem happens to all three charger units! Its like there is no battery and they do not start charging. Self diagnosing of the charger (status pins on their connector) reports STATUS OK. Being an electrician myself, I opened one unit and there are no signs of damage, all FET and most other transistors measure OK. It seems that the unit does not give the command to start charging, probably because it fails to detect the battery.  Did anybody have such a problem before? Any ideas will be appreciated,  Meanwell company does not even answer to my e-mails..