Working with 3M Mini-Clamp Connectors
This post describes how to prepare wire and crimp the 3M Mini-Clamp connectors to it. Tools needed are a pair of slip joint or channel lock style pliers, wire cutters (or sharp scissors) and a wire stripper or utility knife.
Mini-Clamp II Series 371 Plugs part # 3M 37104-A165-00E. These are the connectors Firefly/Spyder uses for all of their drop cable connections. Easily crimps with a pair of pliers. Available from many sources including Firefly Integrations in Middlebury, IN. Digi-Key is another supplier that offers reasonably priced USPS first class shipping for small quantity lightweight items like this. I suggest ordering extra of these for future projects – or – in case you make a wiring mistake. Once crimped I do not believe they can be reused (although I never tried to resurrect one).
I really like these connectors. They are much less complex than other connector styles, require no special tools to crimp and are easy to work with. RV-C does not specify any connector requirements, however these are perfectly suited to the job. This connector style has been adopted by Spyder/Firefly and is used on all their equipment, plus some other OEM suppliers are using them as well, such as Garnet.
The connectors, as well as “official” RV-C drop cable are available from Firefly Integrations in Middlebury, Indiana. The will be happy to sell you some. From my last purchase in 2016 they charged me $0.26/ft for the cable and $2.50 for the connectors. The connectors can also be ordered from several internet sources, search on the 3M part numbers in the diagram above. I know of no other source for the “official” RV-C drop cable however CAT-5 or CAT-6 can be substituted as long as it is 20, 22 or 24 gauge, stranded and unshielded. Simply cut off the two unused pairs.
- Strip 1 to 1.5″ of the outer cable sheath to expose the conductors.
- Generally arrange the wires in the correct order. Starting at the clip with the blue side up the color order is Red/White/Blue/Black.
- Grasp the 4 exposed conductors and while maintaining the proper color order, align them closely together. The lengths probably won’t be even, so trim the ends so they are all flush.
- Insert them into the wire ports in the blue plastic being careful to maintain the proper color order starting with Red closest to the clip (pin 1).
- Make sure all 4 conductors go all the way in.
- Now while holding the wires firmly in place, squeeze the blue crimp area with a pair of pliers. Slip joint pliers or channel locks work best because they provide a more even squeeze. Even so, it’s not a bad idea to rotate the pliers position 180 degrees and squeeze from the other side to ensure an even crimp.
- Before crimping: