I’ve got my van fridge connected to the Load output of the MPPT charge controller as this gives me battery protection. All the diagrams I look at shows loads connected direct to the Battery. Am I ok doing it my way or are there some losses to factor in. I also have a grid charger Blue Smart IP65 for hook up when the sun is poor.
I am very new in this, so I can’t answer you question. But I can tell you my experience because I just installed MPPT 75/15 in my van, not DIY but via some “professional” installer and they didn’t connect anything to the LOAD output of the MPPT, so I can’t measure any load … I went back to the installer and he asserts that “load output doesn’t measure loads but it’s an output to power some small loads directly from panels”. Does it sounds very weird to me. From user manual it’s clear LOAD is for measure: I am right?
The load will be measured, but the installer is right, it is meant for low powered loads. The output is only rated for the same amps as the controller, so in your case 15A. Some fridges pull a very high current at start up, they may only be rated at say 50W = 4A at continuous running but for a split second can pull 300W to 500W = 25A to 40A. This may be OK, this may not, some people have fridges on their load output and it is fine, especially if they are smaller than I have quoted. The professional installer is making an installation that he has to guarantee will work so he makes the most robust install. If you are DIY and take the risk of damaging your equipment then you can take a different approach.
Thank you @pwfarnell for your precious and very clear answer. I’ll be checking my equipment’s manual to know how much they can pull.
Let’s say I’ll go DIY, taking the risk: if something will go bad, what I’m going to damage? The MPPT? The “overpulling” equipment? Or all the electric system? Sorry but I’m a newbie…
The MPPT would get damaged. It has a fuse on the battery side but this would not protect against very short term high current like starting a fridge.