Opinion needed on these Victron controllers

[bonvanroulez]

I'm ready to place an order for a Victron charge controller, before I do would appreciate input on which one I really need.

The unit is either the SmartSolar mppt 100/20 or the SmartSolar mppt 100/30.  Jpg of data sheets from Victron are attached.

Solar is 3 x 100 watt Renogy mono panels, the battery bank is 12 volt (2 x 6 volt GC2s). I would like to be able to run the panels in series when conditions are right, can also run parallel.

The Smartsolar controllers have bluetooth built in so am assuming I can monitor and control the unit from the smartphone app without buying the external dongle.

The 100/20 looks like it should be okay, though might be cutting too close to the max ratings, so maybe I need the bigger 100/30 controller. But its an extra $70 so if the 100/20 will work comfortably I'd like to save the money. I'm out of room for any more panels so future upgrade is not an issue.

Thanks! 

100/20 data sheet


100/30 data sheet

 

[John61CT]

Not even close to hitting the limits on the 100/20, that's fine.

If you have room for four, one pair per 100/15 x2 I bet delivers more output per dollar?

 

[bonvanroulez]

Not even close to hitting the limits on the 100/20, that's fine.

If you have room for four,  one pair per 100/15 x2 I bet delivers more output per dollar?

No more room for 4x, so if the future ever requires additional power it would have to be a portable/standalone.

Thanks for confirming the 100/20 will work.

 

[UptownSport]

Have 300w in series on the 75/15, never becomes more than warm.

No data connection without spending more $$, however.

Also a thread on the 75/15 connections

 

[John61CT]

Have 300w in series on the 75/15, never becomes more than warm.

No data connection without spending more $$, however.

Also a thread on the 75/15 connections

I assume you know you're overpanelling by 80W there?

Not an issue in average conditions, greater output per SC $.

But during those rare peak times when panels are actually putting out their rated watts&amps, you could be throwing away over 20%.

I'm usually advocating some overpanelling, others hate the idea of any at all.

You are still well under the limits though wrt doing any actual damage to the SC.

 

[Weight]

My recommendation is use the larger of the controllers. Never a good idea to cut electronics a "bit less" than the system needs. You have nominal 300 watts. The smaller controller is rated at less that that. It is only $70. Sell a kidney.

 

[tx2sturgis]

 Sell a kidney.

I know people who constantly abuse their liver....apparently we don't need it anyway.

Yeah just sell that.

 

[John61CT]

My recommendation is use the larger of the controllers. Never a good idea to cut electronics a "bit less" than the system needs. You have nominal 300 watts. The smaller controller is rated at less that that. It is only $70. Sell a kidney.

Isc (20A) and Voc (100V) are the specs of concern for not overloading the controller, with current there's more leeway than with voltage.

The maximum **charging output** of 290W is a theoretical calculation, not a safety limit.

The overall output from those three Renogy panels from a practical POW will never be limited by the 100/20 controller.

Sure $70 may not be much, but why throw it away? better put toward a better bank, or battery monitor, or. . .

 

[rayrey]

it is all POV. When you are sitting in the first clear sun after a few days of crappy weather and watching your controller clipping amps you may think for a few more bucks I could be collecting those amps before the clouds roll back in.

 

[Weight]

"monitor, or. . . " buy us a round, my liver still works half the time.