Hi William

The fortress 12kw and the eg4 both say the max wire size is 3/0. 

I have used 3/0 ferrules and they fit perfectly 

Jay

On Sep 2, 2025, at 10:08 PM, William Miller via RE-wrenches <[email protected]> wrote:



Friends:

 

Thank you for all of your input on this question.  I feel it only right I report back how this turned out

 

I tried a crimper like this:

 

 

<image002.jpg>

It left a jagged ridge on both sides of the ferrule where the dies met.

 

The crimper below was suggested but I have not tried it:

<image007.jpg>

This was suggested but I have not tried it either:

<image006.png>

 

I had tried a similar crimper to the two above but it expanded the width of the ferrule beyond what the lug would accept.

 

Here is what several of you suggested:  Slip the ferrule over the strands and insert it into the lug and let the set screw do the crimping for you.  We tried this but the 4/0 ferrule when not crimped would not fit into the battery lug on a fortress Envy 12.  The Envy 12 installation manual indicates a wire range of 1/0 to 3/0 and the placard inside the wire compartment door says up to 4/0.  The lug seems tight for 4/0.

 

Here is what we did:  Back in the days of the Trace DC250 (maybe 1988-ish) we had trouble wrangling all of the strands of a fine-stranded 4/0 battery cable to all fit in the lug without a bunch of strands poking out.  I found some thin (~35 gauge) copper sheet at a local hobby shop.  I would clean and polish it shiny and cut a little strip of the sheet slightly wider than the strip length and long enough to wrap about 1-1/4 times around the strand.  I would wrap it tightly around the strands and hold it temporarily in place with a thin cable tie.  I bent the end of the sheet into a chamfered shape to help guide the assembly into the lug.  After I got it started I would snip the cable tie, fully insert the cable and tighten the set screw.  I never had one of these connections fail.  This is what we did on the Envy 12 battery cables. 

 

The next day we removed all of the set screws and inspected the connections.  They all looked great:  The copper sheeting had not twisted, it had a nice, shapely dimple and, peaking up into the lug, the cable looked to be well seated.

 

I hope this feedback helps someone, someday.

 

William

 

Miller Solar

17395 Oak Road, Atascadero, CA 93422

805-438-5600

www.millersolar.com

CA Lic. 773985

 

 

_______________________________________________
List sponsored by Redwood Alliance

Pay optional member dues here: http://re-wrenches.org

List Address: [email protected]

Change listserver email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org

There are two list archives for searching. When one doesn't work, try the other:
https://www.mail-archive.com/[email protected]/
http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org

List rules & etiquette:
http://www.re-wrenches.org/etiquette.htm

Check out or update participant bios:
http://www.members.re-wrenches.org

_______________________________________________
List sponsored by Redwood Alliance

Pay optional member dues here: http://re-wrenches.org

List Address: [email protected]

Change listserver email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org

There are two list archives for searching. When one doesn't work, try the other:
https://www.mail-archive.com/[email protected]/
http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org

List rules & etiquette:
http://www.re-wrenches.org/etiquette.htm

Check out or update participant bios:
http://www.members.re-wrenches.org

Reply via email to