Data/voice jack FREE cabling and networking Helpdesk
 Question by Dave V posted 10 Jul 2007
 Data/voice jack
In my house there is an ON Q legrand system and my Phone jack is actually a rj45 jack connected to the ON Q with CAT5e cable.. with all 8 wires connected on the jack and the terminal in the ON Q...

my questuion is:
can i use this as-is for phone service or do i need to disconnect some wires on the jack and in the ON Q box...
basically woul there be an issue with voltage or somethig to be concerned about, or is it ok to plug in my phone to that jack... as i do not wish to blow up my new house lol...

currently i use the connection for data (my PC), but want to use it for voice (phone) from now on...

thanks in advance :)
 Answer by Dmitri Abaimov posted 19 Sep 2007
Dear Dave,

Go right ahead and plug your RJ11 phone cable into the RJ45 jack. Their pairs #1 coincide in such connection thus providing connectivity for one-line phone. It used to be the case that some lower quality RJ11 would damage pins 1 and 8 in the RJ45 jack but it has been years since I last saw this happening, so you should have no problem with using phone cords in RJ45 jacks.

Dmitri Abaimov, RCDD

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