Solar Controller Wiring Mystery

Start over and do it correctly.

This is for a different controller, but is interesting for the wiring for the test.

STEP 3: Test Blocking Diode – A unit with a shorted diode may blow any in-line fuses
and damage the power FET (see above). A unit with an open diode will not
charge the battery.


1) With all ASC connections removed, connect the panel(+) to the ASC’s “ARRAY(+)”; panel(–)
to the ASC’s “BATT(+)” (no battery connection).


2) Measure voltage at ASC. Meter(+) to ASC’s ARRAY(+), meter(–) to ASC’s BATT(+)
terminals. The reading should be .3 to .6 volts. A very high reading (16-20 volts*) would
indicate an open diode, a very low reading (0 to .2 volts) would indicate a shorted diode.
Units with open or shorted diodes are defective.

Still can't figure it out. Not going to go back and take a chance on wrecking his solar. :)

A PWM passes battery voltage through to the panel, so not clear what the paths are. Another ASC test is to wire the panel to the array terminals and no battery at all, then measure voltage at the battery terminals--should be 14ish or whatever the high set point is set at.

http://specialtyconcepts.com/SPECIALTY_CONCEPTS_PDF_FILES/ASC_INSTRUC_MANUAL.PDF

More coffee needed to tackle this puzzle some more!

can you hook it back up wrong and test!!!

with a pos ground the panel pos and batt pos are common so the panel is shorted with both leads connecting to pos, zero voltage max current (Isc).

The batt is connected to 2 neg terminals that the controller switches, if closed would short the battery, try with no over current protection!!!

Controller is "common pos ground" but neither panel nor controller is grounded to RV frame. Battery is neg grounded to frame. This is all normal for controllers like this.

However, it is ??? possible it makes a diff for this mystery ????

https://www.epsolarpv.com/upload/cert/file/1811/LS-SMS-ELN-V3.2.pdf

ISTR it just means which path the controller switches.

I’ll venture an admittedly pure WAG:

Is it possible that the ‘output side’ of the controller is simply a on-off type switch??...If so then,

a) Neg Array to Pos controller output side, thru controller, Neg controller output side to batt Neg post.

b) Pos Array to Pos controller input = equalizes within panels depletion zone (Pos) diodes - (no adverse effects).

c) Pos batt to controller Neg input, passing through inductive coupling (??), then completing a path to the array Pos - no conflicts with above item ‘b’...

But to make this madness all possible, how does the coupling become inductive??...Possibly a consequence of the controllers on-off pulsing action...

As I said, this is just a wild arse guess - lol

3 tons, after a shot of Jack