Classic vs Outback

[djsharpe]

I recently added 12 off 190W monos to my cust's existing installation of 12 off 170W. The new installation had a MN150V MPPT & the earlier one had MX60. Although both arrays could have gone on the MN my cust wanted 2 separate devices for redundancy issues. The installation runs at 48V & has 1700Ahr wet bats. It has an Australian made 6kW inverter. The arrays are 3S 4P. I commissioned the system yesterday & the system was at first working to my prediction that the new array would outperform the 5 year old existing one. My cust lives in a hilly area & we are in winter in southern hemi and there were sunny breaks. In sunlight the new out-performed the old but in cloud where outputs were 3-5A the old did better than the new. I also swapped the arrays & the difference was higher. I have screenshots if anyone wants them. I noticed that the MN runs hotter than the Outback also. Have I got a faulty MN or is this as to expectation? 

[Halfcrazy]

I would say the Classic "Should" feel Hotter than the MX60. Remember the MX60 is inside a metal box and the heat is dissipated through everything. Where the Classic intentionally sends it right through the case to the exterior to allow the electronics to run cooler. We sort of messed up a little when we designed and built the MX60 

As far as power output. Are you watching the displays or do you have monitoring on the controllers. Again I have to point out that when we built the MX60 we did not think about accuracy on the meters like we did on the Classic. We always got calls of the MX60 reading 10-15% higher than it really is. The Classic was built with Shunts on both the input and output so it is very accurate.

Ryan

[boB]

The Classic was built with Shunts on both the input and output so it is very accurate.

The Classic's output (battery)  current sense will be more accurate than its input current sense but
is the most important.

Also, the MX60 has more FETs and larger inductors so it may very well run cooler but the
Classic has usually out-performed it, energy output wise.  Well, at least over the FM80
or FM60.  The MX60 was a pretty good unit but still, it would read high as Ryan said.

boB

[djsharpe]

Ill return to site with external shunts & ammeters & possibly another Outback reg & repeat tests. David