# Connecting two black together on slave 3 way switch - Why? **URL:** \ **Category:** Devices & Integrations\ **Created:** [July 17, 2017, 9:20pm UTC](https://community.smartthings.com/t/connecting-two-black-together-on-slave-3-way-switch-why/93093 "2017-07-17T21:20:55Z")\ **Posts on this page:** 1\ **Showing post:** 2
**Author:** ![JDRoberts](https://yyz2.discourse-cdn.com/smartthings/user_avatar/community.smartthings.com/jdroberts/32/56577_2.png) [@JDRoberts](https://community.smartthings.com/u/JDRoberts)\ **Post date:** [July 17, 2017, 10:14pm UTC](https://community.smartthings.com/t/connecting-two-black-together-on-slave-3-way-switch-why/93093/2 "2017-07-17T22:14:39Z")
> [@Azriel\_H](#): > > I just wired my 3 way Z-wave switch and its working fine, but i am not sure HOW it works. ( I am not super electrical inclined, so bear with me ) > > Why is it needed to connect black lines together in the addon / slave switch? Isn’t one of them line and the load? Wouldn’t connecting load and line together force the light to always be on? Electrically, how that makes sense? Someone care to shed a light. Thanks! See if this helps: > [@\[FAQ\] GE 3-Way Wiring](https://community.smartthings.com/t/faq-ge-3-way-wiring/74962): > > I’ve decided to put this FAQ together to help those with questions about installing GE 3-way switches. Definitions of terms: Line: The hot wire from the breaker (usually black) Neutral: The return wire for circuits (usually white) Load: The wire that will be hot when the circuit is completed to your light (usually black) Traveler: In existing 3-way wiring, this wire toggles hot between two switches. In a smart switch 3-way configuration, a smaller charge is looped through the add-on switch. Some things to know: 3-way wiring for smart switches is different than standard 3 way wiring. You cannot use dumb 3-way switches with most smart switches (You must purchase the matching GE add-on switch to wire with your GE smart master switch). If the line is wired into the light fixture, you … The line and load are always part of one loop so if you left them disconnected you wouldn’t have any power to the light. The idea is that you are going to break the loop only at the master now that you are using networked switches. You want the loop to bypass the auxiliary altogether. If the model you have uses traveler wires, The auxiliary will communicate with the master by the physical traveler wire, essentially acting as a remote to the master. If the model you have communicates by radio between aux and master, the neutral will power the radio in the aux. But check the FAQ, it has pictures and everything. 🕶 --- _[View the full topic](https://community.smartthings.com/t/connecting-two-black-together-on-slave-3-way-switch-why/93093)._