Retrofitting lifts with VDS communication

Telecommunications providers are converting their networks from analogue to digital, meaning an end to DTMF communication.

Consequently, if you want to make your lift future-secure and simultaneously save costs, you should invest in a digital communications platform that uses the VDS protocol.

Many emergency telephones today are still based on analogue technology. However, since telecommunications providers are converting their networks, a telephone in a lift might stop working properly from one day to another. The high compression also causes occasional disruption in DTMF communication. Moreover, checking analogue systems is elaborate and expensive.

Every emergency call telephone is connected with a control centre occupied round the clock on a daily basis. The functionality of the system is tested every three days by a control call in the background. If this fails, the call centre informs the lift company. The latter then despatches a service technician to check whether people are trapped. At the weekend, several hundred notifications can quickly accumulate.

Digital solution with VDS

By contrast, connection problems between the emergency call telephone and control centre are a thing of the past with digital technology. Even if data packages get stuck briefly once in the network, they still arrive. There are no more incorrect malfunction reports and lift companies can considerably reduce their inspection expense.

Ideally, digital communication systems should use the VDS protocol. It has established itself as the standard for the transmission of hazard notifications via TCP/IP and as a result can be used universally in the security sector. If a control centre receives an alarm per VDS, it immediately knows in what building and on what floor it was triggered.

Save costs with intelligent monitoring

A digital communication platform can be connected to several lifts, which collects data about them and makes remote lift monitoring possible. Photo: © Avire

Installation of a digital emergency call telephone provides an opportunity to implement a complete communication platform to which a sensor or control unit can be connected. As a result, lift operators can monitor the condition of the lifts remotely, test alarms, check controls and collect all kinds of data. This enables them to predict when a component has to be repaired or exchanged, for example.

A technician only has to be on site when really necessary. Many problems can already be corrected in advance with predictive maintenance, which in turn can reduce failures and maintenance costs. Moreover, the working time of the technicians can be recorded on site by an in- and output module. Lift operators gain more control over the work actually performed and invoicing becomes transparent.

Mode of installation

A digital communication platform like DCP (Digital Communication Platform) from Avire can be installed without much effort. Modern CAN-bus systems combine all components needed in one module and need only two wires in the lift cable. The voice unit for operation can be mounted on the lift car.

There is a GSM interface for the mobile communications network in the car module and an M2M gateway for machine communication. A CAN-bus connection links the audio modules in the car, shaft and machine-room. The data of the individual modules are despatched to a cloud platform via GSM and merged. This allows the devices to be administered and monitored under a central user interface.

But it needs to be borne in mind that GSM modules are unsuitable for digital communication, since they use the voice channel for transmission to and from the call centre. Irritating noises of the kind one is familiar with from analogue telephony can still arise here, especially DTMF tones. Only replacement by a completely digital solution, such as the DCP from Avire, can eliminate these problems by reliably transmitting the data via the VDS protocol to and from the control centre.

Matthew Davies
The author is a market insight and innovation manager – Americas & EIMEA at Avire

More information: avire-global.com