class for solar

[Dave78Chief]

Before connecting a higher voltage array to a PWM controller, I would recommend reading this morningstar document: http://www.morningstarcorp.com/en/su...vPWM.01.EN.pdf.

In the Array Sizing for PWM Regulators section my interrpretation of this note is recommending you should not do that:

NOTE: The Vmp of the array should be higher than, but as close to, the maximum battery voltage as possible. Vmp significantly higher than max battery voltage reduces efficiency and puts more stress on the switching components of the regulator.

Anyway, the document provides a lot of good information.

Dave

[Perry White]

The way they tell it this morning on the News, Solar manufacturing is about gone under. Might want to wait about 6 months for the prices to come down.

[KJINTF]

Dave

I agree using a PWM controller that connects the PV array directly via a pulse width modulation scheme to the battery bank anything over 17Vdc from the panels is a waste and could harm something. In the "on" position the panel is directly connected to the battery. Might get some warm wires or even worse depending on the PV wattage

Now with the Tristar MPPT controller it's a different story. Ingest a higher voltage down convert via three separate buck converters then do the traditional PWM charging. All is good

[Dave78Chief]

My reason for bringing out the PWM issue was because John's post implied he has the PWM version of the Tristar and I did not want to see him possibly damage it. Rather than let it ride (I do not know what he has), I brought the issue to the surface. Like you said, the MPPT is designed to be used with 12, 24, or 48 Volt arrays as long as the VOC is less than 150 volts. However, using the Mfg documentation to substantiate that fact holds more credance

Dave

[bluepill]

Quote:

Originally Posted by Dave78Chief Anyway, the document provides a lot of good information.Dave

Nice white paper. Thanks for posting it.

[John Hilley]

Thanks Dave78Chief for the information. I do in fact have the PWM controller.

[Dave78Chief]

Your welcome. Solar stuff costs to much to damage it when the information is there to prevent it. Both that document and their Training video say not to use the higher voltage panels (24, 48, etc.) with a 12 Volt PWM controller.

Dave