Interest in mismatched panel test?
Ever since I got my first set of mismatched panels, seeing then react to different conditions convinced me they would interfere with a MPPT controllers ability to track. With the TS-MPPT-60 I could lo...
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The clouds I needed to do a crash test never came so later in the evening I decided to create a crash. The system had been through absorb and was running low in float with the three panels in series when turned on the heater to get the voltage down on the battery. Even though the voltage dropped past the point I would have expected the controller to switch into bulk. The amps got up to 14+ but it stayed in float.
Covering the mono in a translucent covering like wax paper that allowed enough light to keep the arrays Voc up but the Isc crashed below two. The Vmp of the array dropped to 50v but it didn't come back up when I pulled the cover. i covered the poly and it didn't seem to change much but there was some recovery in the Vmp when I pulled the cover. I turned off the load and let it run for a while and the amps never came back up and it stayed in float.
I also wanted to do a parallel shade test so i switched the leads around and still, the controller wouldn't come out of float. The two polys in parallel actually did better that the three in series were but no bulk with the battery low.
I disconnected the array again but made sure the controller was saying night before reconnecting. This time it came on and went into bulk. It was after 6 pm and the amps were weak but better than the first time I tried to get the two polys going. I covered the 250w with the paper and the Isc dropped a amp. This time the system recovered when I pulled off the cover.
so this is the second time when being in a lower light condition seems to crash the array in series and with different panels. There is a possibility that by the time I ran the test that the mono was already running so low that it was somehow messing with the array ability to stabilize or the controller's ability to read it or go into bulk. Even when the 220w did seem to function, the array current was lower than with just the polys in parallel.
The controller didnt get stuck when one of the polys crashed in parallel or when I did shade test on the three 250w polys in series. Only when there is a off panel that drops in lower light. I wonder if it would get stuck in the morning when the polys fire up before the mono does.
Covering the mono in a translucent covering like wax paper that allowed enough light to keep the arrays Voc up but the Isc crashed below two. The Vmp of the array dropped to 50v but it didn't come back up when I pulled the cover. i covered the poly and it didn't seem to change much but there was some recovery in the Vmp when I pulled the cover. I turned off the load and let it run for a while and the amps never came back up and it stayed in float.
I also wanted to do a parallel shade test so i switched the leads around and still, the controller wouldn't come out of float. The two polys in parallel actually did better that the three in series were but no bulk with the battery low.
I disconnected the array again but made sure the controller was saying night before reconnecting. This time it came on and went into bulk. It was after 6 pm and the amps were weak but better than the first time I tried to get the two polys going. I covered the 250w with the paper and the Isc dropped a amp. This time the system recovered when I pulled off the cover.
so this is the second time when being in a lower light condition seems to crash the array in series and with different panels. There is a possibility that by the time I ran the test that the mono was already running so low that it was somehow messing with the array ability to stabilize or the controller's ability to read it or go into bulk. Even when the 220w did seem to function, the array current was lower than with just the polys in parallel.
The controller didnt get stuck when one of the polys crashed in parallel or when I did shade test on the three 250w polys in series. Only when there is a off panel that drops in lower light. I wonder if it would get stuck in the morning when the polys fire up before the mono does.
