Tracer MPPT?

[inetdog]

I have to take issue with the absolute statements there.
During the Bulk stage an MPPT controller is still delivering PWM in the sense that you use it since the DC output comes from the low voltage side of a DC to DC converter that is operating on high frequency pulses.

And in Absorb and Float the MPPT controller is not necessarily pulsing the DC-DC converter output, it could be changing the converter operating point to produce a lower output current by taking less current from the panels. The voltage waveform on the output in that case would be no noisier than the waveform during Bulk. Same frequency, and not necessarily even a noticeably different pulse width.

[Roland Saul]

In reply to previous questions:

Yes, my pump is 12 volts. It is a spray pump meant for a tractor. It draws 10 amps at 12 volts. And yes, as stated previously, I tested my batteries using a glass float hydrometer with temp. correction scale.
I checked the voltage with my voltmeter, again calibrated accurately as far as I can test, to see what the voltage reading was at full charge. in my case, full charge from the Tracer mppt controller seems to leave my batteries reading 12.6 -12.7 volts. I assume this is normal but I welcome any clarification if it is not.

My point to the OP was that while the controller seems to function, it gives suspicious SOC readings as if my batteries were extremely low capacity, or if the electronics/SOC software in the Tracer were bad. My controller is the 20 amp version, while the OP's is the 30. I don't know if the two models share the same circuitry/software, but I thought it might shed some general light on the quality side of the Tracer products. The controller is functioning albeit somewhat strangely. It may be that I have two coincidentally flawed batteries, and the Tracer is accurate, but at this point I suspect not.

You may now return to your off-topic argument.

[jflorey2]

Once you've reached absorb, it would be very hard to tell the difference between an inexpensive pwm controller and mppt controller - since BOTH use the pwm technique to limit the CV or constant voltage stage.

Look at both a PWM and a MPPT charge controller in absorb (or float) with a current probe. It will be immediately apparent which is which.

[Mike90250]

Look at both a PWM and a MPPT charge controller in absorb (or float) with a current probe. It will be immediately apparent which is which.

Maybe.
both my Classic and Morningstar MPPT controllers have a MPPT Float mode, MPPT Absorb. Only when demand is low, do they fall back to simple PWM. But once PWM can't keep up, they go to MPPT, and can stay in float or absorb.

(Somewhere, the screen captures I took of these conditions, live on my computer, but so far, not where I have looked)