DIP switch settings on the Samlex SCC-30AB solar charge controller

[fbalexander]

I used my cell phone to take a picture of the back of this controller in an effort to see how the DIP switches were set. It appears that ETI installs the controller using the "default settings". DIP #1 default is for a 12v system. DIP #2, 3, &4 default is set for "Sealed battery, 14.0 Absorption, 13.4 Float and 'none' for Equalize" DIP #5 default is "manual equalization".

The three middle DIP settings (2, 3, 4) allow for 3 "Flooded battery" settings that use absorption rates ranging from 14.4 to 14.8 and equalization rates from 15.1 to 15.3. It seems to me that I should adjust the DIP settings for one of the "Flooded battery" settings and perhaps the third with the higher voltage ratings. (I have the dual 6v interstate batteries). Am I off on my thinking here?


Fred Alexander

[rbryan4]

Originally Posted by fbalexander

I used my cell phone to take a picture of the back of this controller in an effort to see how the DIP switches were set. It appears that ETI installs the controller using the "default settings". DIP #1 default is for a 12v system. DIP #2, 3, &4 default is set for "Sealed battery, 14.0 Absorption, 13.4 Float and 'none' for Equalize" DIP #5 default is "manual equalization".

The three middle DIP settings (2, 3, 4) allow for 3 "Flooded battery" settings that use absorption rates ranging from 14.4 to 14.8 and equalization rates from 15.1 to 15.3. It seems to me that I should adjust the DIP settings for one of the "Flooded battery" settings and perhaps the third with the higher voltage ratings. (I have the dual 6v interstate batteries). Am I off on my thinking here?


Fred Alexander

I would probably leave it at the factory defaults. The absorption, float and equalization are automatically controlled with dip switch 1 on. All you're changing by engaging switch 2 thru 4 is the algorithm of these automatic cycles, and slightly modifying the voltage. From what I can see in this table, dip 1 on and the rest off is about right for the Interstate batteries - or at least close enough that it shouldn't matter.

[jamman]

I would go with battery type 7 for the dual 6V configuration.

See: http://www.escapeforum.org/forums/f1...ries-5405.html
(I think the absorption voltage in the first post is a typo - Jeff accidentally copied the bulk voltage.)

[rbryan4]

Originally Posted by jamman

I would go with battery type 7 for the dual 6V configuration.

See: http://www.escapeforum.org/forums/f1...ries-5405.html
(I think the absorption voltage in the first post is a typo - Jeff accidentally copied the bulk voltage.)

Maybe I'm reading it wrong. Interstate's recommendation for optimum absorption voltage is 14.46V, no? The factory default would put it at 14.6 - pretty close.

[jamman]

See post #2 in the referenced thread.

Bulk 7.23 volts in a dual 6 volt arrangement 14.46
Absorption 7.65 volts in a dual 6 volt arrangement 15.3
Float 6.7 volts in a dual 6 volt arrangement 13.4
Equalization 7.8 volts in a dual 6 volt arrangement 15.6

[Steve Clark]

........What The?.............

[rbryan4]

Originally Posted by jamman

See post #2 in the referenced thread.

Bulk 7.23 volts in a dual 6 volt arrangement 14.46
Absorption 7.65 volts in a dual 6 volt arrangement 15.3
Float 6.7 volts in a dual 6 volt arrangement 13.4
Equalization 7.8 volts in a dual 6 volt arrangement 15.6

Ah, I get it. So, setting it for type 7 makes sense. Probably good to check the electrolyte levels more frequently though at the higher charging voltage.

[jamman]

Originally Posted by rbryan4

... Probably good to check the electrolyte levels more frequently though at the higher charging voltage.

Absolutely. I check about every 6 weeks.

[fudge_brownie]

Fred,
I think you are on the right track to adjust your DIP switch settings to the higher charge rates for absorption and I agree with Doug and go with Battery Type 7. I realize you do not have a L-16 battery but the charge rates for the dual six volt batteries are what Doug indicates.

Bulk 14.5
Absorption 15.3
Equalization 15.6

The most important rate is the Absorption. Using Battery Type 7 will get you the closest to the Interstate recommended rates.

If you would like more information on these charge rates from Interstate, visit their web page for the recommended levels of a single 6 volt, then double the result for dual six volt. Quite high charge rates. The Trojan T-105, a comparable battery to the Interstate uses similar high charge rates.

As always, when charging at these rates be sure the battery box is properly vented and the batteries are filled to the proper level with distilled water.

[fbalexander]

Thank You Paul and all! I will adjust to Type 7 and monitor the levels regularly. Speaking of that, would "proper levels" be just above the plates or is it to the bottom of the plastic of the filler holes?



And... would the rational of ETI leaving the "default" DIP settings be "it's safer that way"?


Fred

[fudge_brownie]

Yes and yes.


Above the plates and at or below the fill tube.


I could only guess as to the rationale but your guess would be my first.

[fbalexander]

Thanks again Paul!

Fred

[cpaharley2008]

using distilled water, only.

[Brian B-P]

Maintenance instructions from battery manufacturers typically say to top up with water only when the battery is fully charged, to avoid accidental over-filling since the electrolyte expands during charging. But do ensure that the plates are at least barely covered at the start of charging.