Using EZ RJ45 Connectors with PoE

Some RJ45 ports are a tight fit and the end of the connector can be pushed hard against the back of the port. In most instances this is not a problem, but because of the way the EZ RJ45 system works, it is possible that this can physically affect conductor spacing causing shorting with PoE and possible RFI/EMI issues.

Our recommendation in these circumstances is to slightly modify the way the connector is crimped. Prepare the conductors as usual, insert the conductors into the connector and push home as far as possible in the normal way. Ensure that there is plenty of jacket inserted. Then, using a good side cutter, (our part number 450128, for instance) trim the conductors flush with the connector. Pull back the conductors very slightly so that the ends are concealed within the connector, then crimp as normal with the crimp tool.

Inserting the connector into the port should now result in a solid snap into the port which would not have been the case if the conductors were snagging at the back. This should solve all of the issues above and best of all, it will prevent you resorting to the old-fashioned way of terminating RJ45s!


Our experience has shown us that when the crimp tool trims the ends flush with the connector it can have the effect of stretching the insulation slightly. When the termination is complete, the insulation then shrinks back exposing the ends of the conductors. Using a tight port can then have the effect of distorting these conductors and reducing the spacing between them causing the RFI or EMI issues.

This problem is exacerbated when the tool does not have sharp cutting blades. These are available as spares, part number 450126 for the EZ RJPRO HD tool and part number 450127 for the EZ RJ45 crimp tool.