Pigtails to Ease Solar Attachment, Other Newby Question

tombeaux

Pigtails? -  I took delivery of a Renogy 100 watt solar panel/waterproof controller package. It is a pain to remove my sewer hose, remove the battery box strap, unsnap the battery box cover and then attach the clips to connect the solar apparatus. Can someone point me to a pigtail installation scenario that will allow me to open the cover, attach the clips and be done with it? I understand correct wire size is an issue as is even the correct connectors to use with the wire. I want to make sure I get the most out of the solar apparatus. 

2nd question - I have to choose the correct battery type with the controller. I have an Interstate Marine/RV SRM-24 Deep Cycle. The specs say it is "wet" as opposed to dry. Does that mean I would choose "Flooded" as the battery type? 

rfuss928

Attach something like this to the battery and get the mating connector for your solar.

https://www.ebay.com/itm/BATTERY-TENDER-QUICK-CONNECT-CABLE-W-SAE-2-PIN-RING-TERMINAL-HARNESS-DELTRAN/161089041262?hash=item2581a7b36e:g:5CMAAMXQaZxSEZ6f

Sharon_is_SAM

@tombeaux, I take it you have a 2018 Tab that no longer has the solar port on the tub.  Bob's example above will work as the Battery Tender brand and the Renogy brand have the same polarity, so I think you can just plug the panel cables into the above SAE connector using an MC4 to SAE adapter.

If your battery box has a hole in the side, just bring the above cable out through the hole so it is easy to access when you use your solar.  A regular battery is a flooded lead acid battery and is considered wet and you need to add distilled water from time to time.  Choose "flooded" on the controller.

rajamar

@tombeaux
Does the cable coming from the panel/controller have any connector or is it just bare wire?

Sharon_is_SAM

I think the renogy cables have an MC4 connector then you need an MC4 to SAE connector.  Most people add extensions so you need to factor in those connections, too.

ScottG

@tombeaux, if you are going to add a pigtail anyway, you could just equip it with the more robust MC4 connectors and eliminate the need for the MC4 to SAE adapter. I did this so I could disconnect my controller for standalone use. You can see the pigtails in this photo--the other end would be connected to the battery with ring terminals. (Ignore the second pigtail. You would only need one for what you describe.)

Ratkity

I did the same as @ScottG!

rcuomo

Here’s how I setup my Renogy suitcase. I cut off the alligator clips and replaced with a standard SAE plug and mounted a SAE receptacle on the tub. I terminated the leads with soldered ring connectors to attach the leads to the battery.  Everything is 12 gauge.  I purchased the SAE connectors from John Drake Services:  www.solarseller.com.  The receptacle (roof connector with plug) was $7 and the additional SAE plug (9" lead) was $3.  I used the additional plug to terminate my $5 Harbor Freight battery tender.

rcuomo

BTW, I already have 20' extension cables with MC4 connectors on my suitcase.  So all I had to do was keep the MC4 connectors in place and cut off the clips to replace with SAE connectors.  Much easier to disconnect with SAE since you don't need the MC4 tool.  If I want to use the clips I have another setup with the clips terminated with the SAE connector.

tombeaux

rajamar said:

@tombeaux
Does the cable coming from the panel/controller have any connector or is it just bare wire?

It has alligator clips to attach to the battery terminals.

tombeaux

rcuomo said:

Here’s how I setup my Renogy suitcase. I cut off the alligator clips and replaced with a standard SAE plug and mounted a SAE receptacle on the tub. I terminated the leads with soldered ring connectors to attach the leads to the battery.  Everything is 12 gauge.  I purchased the SAE connectors from John Drake Services:  www.solarseller.com.  The receptacle (roof connector with plug) was $7 and the additional SAE plug (9" lead) was $3.  I used the additional plug to terminate my $5 Harbor Freight battery tender.

Wondering why you chose SAE over MC4 Connectors? Great idea on the battery tender addition. 

tombeaux

ScottG said:

@tombeaux, if you are going to add a pigtail anyway, you could just equip it with the more robust MC4 connectors and eliminate the need for the MC4 to SAE adapter. I did this so I could disconnect my controller for standalone use. You can see the pigtails in this photo--the other end would be connected to the battery with ring terminals. (Ignore the second pigtail. You would only need one for what you describe.)

I think that's the ticket for me (and maybe I'll add a plug for a battery tender at the same time). Did you use 10 or 12 gauge wire?

Sharon_is_SAM

The MC4 connectors require a small tool to disconnect and even with that, can be a challenge.  We wiped some dry lube spray on the MC4s and it helped.

pthomas745

I filed down the "points" on the MC4 connectors to make separating them easier.  Why does everything solar seem to be so difficult?

ScottG

@tombeaux, I think I used 10g, but 12g is more than adequate for the amperage from a 100W panel if that's what you have on hand. The biggest concern is voltage drop between the controller and the battery, but we are talking a pretty short piece here.

Either way, be sure you have a fuse on the positive line between the battery and controller--the size of the fuse is determined by the capacity of the controller (often 10A for a 100W system). I incorporated mine into the pigtail, but you may already have on on the cable from the panel/controller.

I used Renogy's MC4 connectors and have no trouble getting them apart without a tool. The tool is helpful to have for the initial assembly, as is a decent ratcheting crimper.

rcuomo

Tombeaux, I used SAE just because it’s easier without the MC4 tool as mentioned. My controller is part of the suitcase. Everything else is MC4, from the controller and to the 20’ extension cables to ensure tightness and water tight sealing. But for the simplicity of the disconnect that anyone can use I found the SAE connectors to work well. Plus they are dirt cheap compared to MC4 connectors. 

ScottG

pthomas745 said:

I filed down the "points" on the MC4 connectors to make separating them easier.  Why does everything solar seem to be so difficult?

As someone recently said to me...

"If it was easy it wouldn't be worth it!"  :-)

tombeaux

Thanks for all the information!