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Splitters and In-Line Filters
Central Splitter
Broadband (ADSL, DSL, ADSL2 & ADSL2+) generates noise on the phone line which causes problems for anything connected to that line other than the computer modem.
A Central Splitter can be fitted in a way that eliminates the need for any additional filters in the house.
Central Splitters are installed to:
- ensure faster Broadband speed
- eliminate line noise
- avoid problems with monitored alarms
- eliminate unsightly inline filters
Why alarm systems require central splitters
Alarm systems, when wired correctly for monitoring, process the phone line first before it has the opportunity to travel throughout the premises or to you modem.
This is referred to as Mode 3 wired. The purpose of wiring your alarm system to mode 3 configuration, is to ensure it is able to dial out in the event of a break in, regardless if the phone has been accidently left off the hook or if the phone is forcibly removed.
If the ADSL line is the same line being used in monitoring the alarm system, then a good quality Central / Remote Splitter must be fitted to the premises ensuring that there is no broadband signal being processed by the alarm.
In short, alarm systems hate ADSL broadand and modems hate alarms.
Failure to do so can result in ADSL drop outs, slow speeds, synchronisation problems, phone lines cutting out etc.
The benefit of central splitters with your existing phone cabling
Line health will be dependent on the existing phone cabling.
Energy is required for ADSL signals to travel along phone cables and turn corners. Therefore, more phone cables / extensions (Star wiring) or phone points connected to the line will result in a poorer quality line or higher line attenuation.
The same goes for corrosion on the line. The more corrosion, the higher the resistance resulting in a poorer quality signal.
The best way to ensure the best quality signal is to have one phone point wired to standard or install a good quality Central / Remote Splitter.
A Central / Remote Splitter will allow many phone line extensions without interference of the ADSL signal to the modem.
Filters
Filters perform the same function as a splitter, but instead of dividing the signal into two parts (ADSL/Voice), filters actually block the ADSL signal to allow the voice signal.
