Anybody have experience with Specialty Concepts charge controllers?

[E92FF]

I am new to solar and and having trouble making sense of my Specialty Concepts Mark 15 controller. It’s on an RV I recently purchased with a 200W panel and a pair of 6 month old 12V deep cycle lead acid batteries. I have several questions so I will list them separately below. I am also attaching a pic of the controller to help make my questions a little more clear. I appreciate help anybody has to offer!




1 the controller only has power to it during the day. At night it is blank. I found a PDF online that suggested this is caused by a bad ground at the battery. I checked all connections and they are correct per the wiring diagram and appear good.




2 with the display selector switch in the top position (Battery voltage bar graph on) the voltage displayed is less that what is shown with the switch in the bottom position. (Battery voltage bar graph off) I cant believe the bar graph would draw enough current to affect the voltage displayed.




3 the Battery voltage displayed is more correlated to sunlight than the battery condition. It was reading above 13V with sun on the panel but dropped as the sun went down until the display turned off as the sun set.




4 with the switch in the array current position I get .01 or .00 But the charging light stays on. I have yet to see the charged light come on. I even tried to run the batteries down and checked it in full sunlight.




5 in the wiring diagram on the PDF there is a “bar graph selector” with 4 pins. It says to place a jumper across both pins, or only across one pin for a storage position. There is a similar label on the back of the controller but there are no pins???




I have checked the fuses as well. With the array fuse pulled the panel goes dead. The battery fuse has no affect. Both fuses at the panel and the fuse on the lead coming off of the battery are good.

[Mike90250]

do you have a link to the manual ?
actually, most RV stuff is junk that's loaded with useless bells and whistles.
A 200w panel is not a lot of power and it's daily harvest will run a couple small LED lights and a cell phone charger. depending on your camping habits, you may find the vehicle alternator is more reliable than remembering to park in the sun and punching holes in your roof.
Or if you are dry camping for weeks at a time, making a couple stowable Sandwich Board arrays you can set in the sun, and run cable to the camper, might make better sense,

[E92FF]

Thanks, all the solar needs to do is keep my batteries charged. A typical camping trip for me is 3-5 days. The trailer has all LED lights and a generator if I need to run anything larger.

Here is the manual I found online:

http://specialtyconcepts.com/SPECIALTY_CONCEPTS_PDF_FILES/MARK_20_INSTRUC_MANUAL.PDF

[E92FF]

I think I need to check continuity of the wire between the controller and the battery. Everything is connected properly and is clean. Maybe there is a break in the wire somewhere.

[Mike90250]

Yep, you got some wiring to check. the controller is so dumb, it should still function

[E92FF]

I think I fixed it! I checked my battery voltage at the back of the controller and only had 4 volts. I checked the batteries and they had 12.7. The terminals looked fine but I wire brushed them and the connectors and put it back together but still only had 4 volts at the controller. There is an inline fuse at the positive terminal so I checked and I had 4 volts on the fuse but 12 Volts inside the fuse housing on the battery side of the fuse. I wire brushed the connections in the fuse holder and each end of the fuse and now I have 12.7V all the way to the controller! I suspect when the sun comes up tomorrow my other concerns will be sorted out as well.

Thanks for accepting my membership and taking the time to read all this. I think typing it all out helped me see the problem.