Panasonic KX-TVS80 User Manual

INTEGRATING THE VPS WITH PANASONIC KX-T PHONE SYSTEMS

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The VPS must also have access to certain PBX features. For example, if the VPS takes a 
message, one way it can notify the mailbox owner is by dialing the PBX's Message-Waiting-
Lamp-On code. Once new messages are retrieved, the VPS dials the Message-Waiting-Lamp-
Off code for that same mailbox owner.

The PBX must have certain capabilities and features to work with the VPS. (Although this 
section includes tests to help you evaluate the PBX, it may be necessary to refer to the PBX's 
documentation for detailed capability and feature descriptions.)

The VPS can only be connected to a PBX that supports SLT sets. Some PBXs need an OPX 
card to provide this connection. However, some OPX cards do not provide all the capabilities 
listed in this section.

Following are the minimum current and voltages that the PBX must supply:

For system users to access VPS services and features, they must be able to send DTMF tones 
from their telephones to the VPS port. As a general rule, SLT sets can perform station-to-
station DTMF signaling; however, many proprietary telephones cannot. Some PBXs need to 
be programmed to make proprietary sets use DTMF signaling.

DTMF Tones

Minimum Loop Current

20 mA

Minimum Line Voltage

7 V DC

Minimum Ringing Voltage

40 V AC