Does ADSL increase the line voltage?

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kaspaas

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Hi,

my alarm company claims that Telkom adds a lot of volts to the phone line when it enables ADSL.

Hence they require me to install another dedicated phone line so I could have radio with phone backup as the insurance requires.

It sounds dodgy to me as my fax machine is running for almost 2 years happily on the same line.

My understanding is that ADSL is merely a frequency signal, and that behind the "mini filter supplied by Telkom" there is no difference between an old analogue line with and without ADSL.

Any technical assistance would be appreciated.

Thanks
 
Just to make sure - you must have the mini filter connected to all analog devices in your home - eg fax machine, telephone, alarm system?
 
You are correct that ADSL uses a different frequency, so your alarm company's claims certainly sounds dodgy. I also have an alarm system that uses my ADSL line and have had no problems with it. As Franna said, slap a microfilter on it and all should be peachy.
 
I have been told tht the alarm system can affect ur ADSL line by a telkom technician.
bt i dnt see how, the alarm system is basically just like a telephone tht fones the call center now n then or wen the alarm goes off.
it'll probably havta be Telephone Line --->Telephone wall socket ---> POTS filter ---> Alarm System

alarm companies normally jus split the telephone line to go to the alarm system and to go to ur telephone jack.

which is like this:

Telephone Line ----> Wall Jack and Alarm System ---- POTS Filter ---> Telephone

So as u can see the alarm system does not go thru the filter.

hope u get wat i mean. hehe
 
Since the alarm system is basically using a modem, technically it should be installed with a microfilter in place.
 
BTW, your alarm company is probably getting confused with ISDN.

ISDN increases the voltage quite alot, but then you should be plugging in to the analogue port on the NT, and not directly into the "raw" ISDN port - that would blow your equipment.
 
I have also experienced with a normal dial up line, wen 2 of the telephone wires touched, it shorted sumthin in my alarm box, which caused my telephone line from not working.
no need to get a seperate line. its jus more of an expense n its nt even needed. but it shud be split after ur microfilter, nt before.
And with regards to insurance, u need to have both Radio and telephone line for a business.
 
ISDN is on a higher voltage, ADSL works on the same voltage. Alarm companies like to pass the buck, i fought with mine and still they don't wanna attach the filter. Newer alarm systems monitor the phone line when armed/other modes so that if the line is cut/below voltage accept levels it triggers it. If your alarm is on the line, depending on design it should cause problems when it goes off for adsl or alarm signal.

Now comes the interesting bit, when the alarm is triggered it cuts the line temporarily to end calls so that it can dial out with its modem. Pending on how the connection is to the modem and alarm box, etc the alarm will not work since it will pick up some extra static on the line(no filter) or if it cuts other lines adsl will not work temporarily while the signal is sent..

Just fight with them and get them to put it in, with RJ11 jacks incase the filter gives up and you need to replace. :cool:
 
Alarms and ADSL

As an alarm technician, I have to agree with the alarm companies. ADSL alarms can definately adversely affect the telephone link to the monitoring companies.
Here are some cases.
1. FBI system. Alarm was set off every time the telephone handset was lifted off the cradle.
2. Caddx system. When I was listening into the alarm line, I definately heard a third tone during the communications.
3. Paradox spectra system. The alarm did not return the line after completion of the signal.

The examples occured at random.
I have asked suppliers and Telkom for some answers, but of course no answers have been forthcomming.
ANyone out there got any suggestions?
 
Oddly the alarm techs by my house just left it all as it was, straight on the main line and everything seems fine except for when the alarm goes off and adsl drops. but other than that it seems to work fine. They say they checked their systems and they recieve their signals etc. whether they have those more complex things though is another question but i do know that as soon as the line is cut the alarm goes off cause the day adsl was installed/turned on i tried to find out where the static sound was comming from(thought it was a wet joint/short) and as soon as the line was disconnected the alarm triggered.(forgot i had it on, it was a sunday..)
 
we had some problems at first, and the adsl always drops connectivity on an incoming call. Every thing seems to be fine now.
 
It's better if at all possible to use a radio link, or at least have a radio backup, because many thieves will cut the phone line to prevent you from phoning the cops.

Also, CHECK that the alarm is not dialling a 0861 number, or your phone bill is going to go through the roof. Especially if you get a "runaway" condition caused by a power failure. If the power goes off for too long, the battery starts going flat.

1. So the alarm sends a "Battery Low" message to the alarm company. In the process it discharges the battery further.
2. Once the recharger gets to a certain point, the alarm sends a "Battery OK" message, which discharges the battery. Loop back to step 1.

This loop can go on for days, and generate hundreds of calls. If they are being made to an 0861 number, such as the ones used by Chubb and ADT, you'll be paying $$$$ at the end of the month.

That's why I prefer radio.
 
I had a simular problem at my house. I had ADSL installed in my first week after I moved in (I ordered the day I signed the contract for them to install the day I moved in.. it was a week late but still add it)

Now my Alarm worked perfect for 6 months, Then telkom came and did some changes to my line, and said the Alarm was causing problems, It was disconnected (just the modem portion), and once proved that it wasn't the alarm it was put back .

2 months later I got a Fault condition on my Caddex system telling me that telephone was not working. I was also given the story that my Alarm can not work on ADSL. I cant understand how it worked for 8 months with out any problems though, 5 Alarm techs later, and paying through my nose each time, I finally just got them to disable the Modem on the alarm.

It does however mean that my secruity company can not tell what is wrong when my alarm goes off and only know that it has gone off (been told the modem sends the alarm condition, not the radio link).

I would love to actually hear what is causing it though or how to fix it
 
It seems as if the alarm systems are using dodgy "telephone equipment".

If fax machines can work on ADSL enabled lines without trouble, why can't alarm systems work with ADSL out of the box?

If alarm systems are cutting costs on the dialer, what is the quality of the rest of the system?

I really can't believe that eg the UK won't have alarm systems that can work decently with ADSL.

PS: The telehone link is for backup only should the radio fail.
 
btw my dial up modem/56k seems to have issues these days when connecting, tried various filter. i would complain but i never use it. perhaps it is too sensitive?
 
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