As the move from copper to fibre phone lines (the Digital Switch) continues, it will affect your emergency autodialler. The reason for this is that whilst copper cables carry a current of 48V within, fibre cable does not carry power at all, meaning that in case of a power failure, the telephone line will fail leaving your emergency autodialler unable to dial out.

The obvious option facility managers and lift owners might consider could be adding a battery backup to the phone line – problem solved! Right? Sadly, it’s not so easy.

The first thing to bear in mind, is that every element of the emergency communication chain will require to be backed up. If one element of the chain fails, then the calls won’t go through.

This means a backup supply will need to be provided for the Optical Network Terminal (ONT) where the fibre line enters the building, the router and, if used, the analogue telephone adaptor (ATA) (see diagram below).


The backup battery should match the minimum 1 hour of standby and 15 minutes of talk time required by British Standards (we recommend that the supply last up to 2 hours to provide an additional level of passenger safety).

Your lift maintenance provider will not be able to supply or install this equipment (they will offer you a digital GSM which they are able to monitor and maintain long-term), it therefore becomes your responsibility to ensure a battery backup is provided,  maintained, and monitored.

For safety reasons, only lift engineers and other qualified personnel can enter the lift motor room or access the control panel so you will most likely have to look for an alternative location to site the phone line battery backup.

Whichever location you choose to install this equipment in, bear in mind it must not be accessible to building users to ensure they are not tampered with (lift engineers should still be able to access it).

The other piece of equipment you must remember to backup will be the Optical Network Terminal (ONT), where the fibre line terminates within the building. The specific model will vary, but you can find an overview of the different types here.

You should also get familiarised with the meaning of the status LEDs on the ONT as they will provide useful information on the status, particularly when there are any events, such as connection issues.

The most important thing to remember is that all these additional pieces of equipment will need to be monitored and tested regularly to ensure they are still functional and reliable – you do not want to find out the backup battery has drained out after a trapped passenger was unable to reach out for help.

An easy solution to proactively prevent being caught out is to monitor the lift emergency phone setup via the AVIRE Hub, which provides live monitoring, reporting and notifications as soon as there is a status change.

For more information on the available solutions to ensure your lift remains safe AFTER the digital switch, contact the AVIRE team today.


Author: Milagros Gamero, EU Marketing Communications Manager at AVIRE

Share article

Related Products