When businesses plan for the PSTN and ISDN switch-off, they think about phones. Fair enough — but the phone line in many premises has quietly been doing other jobs for years. Fax machines, intruder alarms, lift phones, door entry systems, card terminals and even some building systems were wired into copper lines. When those lines go, so does whatever was hanging off them. Here’s how to find those devices before they find you.
What tends to be connected to the old line
- Alarm and monitoring panels — many intruder and fire alarm panels dial out over a phone line to signal a monitoring centre.
- Card payment terminals — older terminals dialled up to authorise transactions.
- Fax machines — still used in some medical, legal and trade settings.
- Lift emergency phones and door entry systems — required to work, and easy to forget.
- Franking machines, building management and telemetry — the things nobody has looked at since install.
Why “just move it to VoIP” isn’t always the answer
Voice calls move to the internet happily. Some analogue devices do not: their dial-up tones and timings were designed for copper, and they can behave unreliably over a converted line. The right answer depends on the device — which is why the first step is an audit, not a purchase.
The realistic options, device by device
- Alarm panels — most monitoring providers now offer IP or mobile (4G) signalling modules that replace the phone line entirely. Talk to your alarm company early; this is their domain and they’ll have a standard upgrade path.
- Card terminals — modern terminals use broadband or mobile data. If yours still dials up, your payment provider will replace it — and if card payments are critical, consider protecting the connection itself with automatic failover such as Viatel Orion.
- Fax — options range from a fax-to-email service (the usual best answer) to an adapter, depending on how much faxing you really still do.
- Lift phones and door entry — these have safety implications; the lift maintenance or door-entry provider should specify the compliant replacement, typically a mobile-network unit.
- Everything else — find out what it is, who supports it, and whether it’s still needed at all. A surprising amount is simply switched off.
A simple audit you can do this week
- Walk the building and note every device with a phone cable that isn’t a phone.
- List the lines on your bill — a line you don’t recognise is usually feeding one of these devices.
- Ring each supplier (alarm, payments, lift) and ask for their switch-off plan.
- Sequence it — replace the devices first; only then retire the lines. This is also the rule in our switching checklist: never cancel a line until everything on it has moved.
Frequently asked questions
Will my alarm stop working when the line is switched off?
If it signals over the phone line and hasn’t been upgraded, yes — which is why alarm companies are moving customers to IP or 4G signalling. Contact yours before the line goes, not after.
Can I keep using fax?
Usually via a fax-to-email service, which is cheaper and more reliable than a machine on an adapter. If you fax rarely, that’s the route.
Does Bellcom replace alarms or card terminals?
No — those come from your alarm and payment providers. What we do is help you map what’s on your lines, plan the sequence so nothing drops, and move your phone system properly.
Don’t let the switch-off surprise you
We’ll help you audit what’s on your lines and plan the move so phones, alarms and payments all keep working. Talk to Bellcom — local, practical, no drama.