Mode 3 Socket
A Mode 3 socket is used to connect an alarm system or a personal medical device to the phone line for monitoring purposes. Most alarm systems can be programmed through the keypad to call,
- A mobile phone
- A back to base alarm monitoring company
Installing a Mode 3 socket must be done before the first phone socket on the premises.
The correct wiring method of a Mode 3 socket, ensures that the alarm system has priority over the phone line and is able to dial out in the case of an emergency.
This is regardless whether the phone line is in use, left off the hook or if a phone has been ripped out of the socket by an intruder.
Mode 3 and ADSL Broadband
If the alarm system is sharing the same phone line as an ADSL / Broadband service, then it must be filtered with a good quality Central Filter of Network Termination Device. Failure to do so will result in internet drop outs, slow speeds and even faulty operation of the alarm system.
This type of installation should only be done by an experienced telecommunications technician who is able to re-configure the wiring to ensure simultaneous trouble free operation of the broadband, alarm and phones.
New and Old style Mode 3 Sockets
There are two different types of Mode 3 sockets being used in the Australian market. The older, more cumbersome style is referred to as a 611 socket.
The newer Mode 3 sockets are partly blue in colour to help distinguish them from ordinary phone sockets.
Common mistakes with installing a Mode 3 socket
- Mode 3 sockets wired in star wiring configuration.
- Mode 3 socket connected after the first socket.
- Data or normal phone socket used instead of a Mode 3 socket.
Our technicians are constantly rectifying the wiring configuration on Mode 3 sockets that have not been installed correctly. Although the above mistakes are not illegal, it is not best practice and is certainly not in the client's best interests.
Who can connect your Mode 3 socket?
Communication cablers who have an "Open" license may install Mode 3 sockets for security systems that connect to the telecommunications network. This includes all industrial, commercial and residential properties.
Communication cablers with a restricted license, can only install Mode 3 sockets in residential and some small commercial properties.
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| Mode 3 Alarm Socket for priority dialing on the phone line Enlarge Image |
Mode 3 Alarm Jack Enlarge Image |
Krone Box Mount fitted with Mode 3 jack insert Can be used in conjunction with a monitored alarm system. Enlarge Image |






