I had 2 Delta Pro 3 ( DP3 ) units running in parallel with their 50 AMP hub bridge. One of the Battery units was defective and caused a tremendous power surge which fried my HVAC thermostat and ECU, coffee maker, Air Purifier, GFCI outlets, and over a dozen outlet surge protectors and damaged two 200 AMP breaker panels. The damages have run into the thousands. One electrician who inspected my system told me that one of his customers had a similar problem with his Eco Flow Ultra except that he didn't have the unit hooked up to the home. I like the EF Delta 2 Max batteries, but the EF DP3 and the 50 AMP bridge is dangerous. It nearly burned down my home.