Installing the HWI-TEL9 into a Key Telephone System (KTS)

This application note describes possible configurations that can be used for installing the HWI-TEL9 with a Key Telephone System (KTS) that contains a central Key Service Unit or Key System Unit (KSU). The configurations were tested using a Panasonic KX-TD308 KSU. There is no guarantee however, that they will work with every manufacturer’s system or programming configuration.

The HWI-TEL9 must be installed on an analog extension. It will not work on a digital extension. The KX-TD308 that was used has 4 analog extensions and the HWI-TEL9 was connected in series with one of them. If the system you are using has a punch-down block, you can run the KSU side of the punch-down block to the inner pair of the HWI-TEL9’s "Outside Phone" jack and run the house side of the punch-down block to the inner pair of the "Inside Phone" jack. Make sure you remove the jumper clips for that pair on the punch-down block.

For Configuration with an Answering Machine or Answering Service:

Install the HWI-TEL9 in series with the analog extension as described above. For configuration with an answering machine, set the HWI-TEL9’s Answering Machine Mode Selection Switch to "Answering Machine" and its ring count set to one (refer to the HWI-TEL9 instructions for details).

For access from an outside line, call in, wait for the answering machine to pick up, then enter your Access Code. Access from inside the house but from an extension other than the one the HWI-TEL9 is on is accomplished similarly to an outside access; call the HWI-TEL9’s extension, wait for the answering machine to pick up and enter your Access Code. For access from the extension that the HWI-TEL9 is on, pick up the extension and enter your Pick-up code. Making the Pick-up Code the same number as the extension that the HWI-TEL9 is on will avoid conflicts with other KSU codes and also creates a consistent number that is used to call the HWI-TEL9 from all inside phones. For example, in the system tested, the HWI-TEL9 was on extension 21. By using 21 as the Pick-up Code, the number that is dialed from extensions other than 21 to call into the HWI-TEL9 is the same number that you dial when accessing the HWI-TEL9 from extension 21.

Configuration with an answering service is similar. With the HWI-TEL9 in series with an analog line, set the Answering Machine Mode Selection Switch to "No Answering Machine" and the ring count to F. Call in from an outside line or an extension other than the one the HWI-TEL9 is on, let the phones ring once, hang up and call back within 5 to 30 seconds and the HWI-TEL9 will pick up. Enter the Access Code to gain access. Note: Some KSUs can be programmed to allow a double ring to differentiate between an inside or outside call. Accessing the HWI-TEL9 using this method may not work when a double ring is present. Keep this in mind when programming the KSU.

For Configuration without an Answering Machine:

Install the HWI-TEL9 in series with an analog extension as described above. Set the HWI-TEL9’s Answering Machine Mode Selection Switch to "No Answering Machine Mode" and its ring count to a relatively high setting (refer to the HWI-TEL9 instructions for details).

For access from an outside line, call in and the HWI-TEL9 will pick up after the set number of rings. Access from inside the house but from an extension other than the one the HWI-TEL9 is on is accomplished similarly to an outside access; call the HWI-TEL9’s extension and it will pick up after the set number of rings. Beware however, that some KSUs can be programmed with a double ring to differentiate between an inside or outside call. The HWI-TEL9 may interpret this double ring as two rings and thus pick up prematurely. Programming a ring delay (if the KSU supports it) on the extension that the HWI-TEL9 is on and then reducing the HWI-TEL9’s ring count setting, may help control when the HWI-TEL9 will pick up.

For access from the extension that the HWI-TEL9 is on, pick up the extension and enter the Pick-up Code. As described above in the Answering Machine Configuration section, a good choice for the HWI-TEL9’s Pick-up Code is to make it the same number as the extension that the HWI-TEL9 is on.

HWI-TEL9 Accidentally Accessed by an Answering Machine

A case has been identified where the HWI-TEL9 can be accessed accidentally by an answering machine when the user calls into their answering machine to play their messages. The following describes the scenario. The HWI-TEL9 is configured in "Answering Machine Mode". The user calls into their answering machine, waits for their greeting message to play and then enters their 4-digit Access Code to gain access to the HWI-TEL9. The answering machine records the 4-digit Access Code tones just prior to being disconnected by the HWI-TEL9. Later, the user calls in to play their answering machine messages and one of the messages on the machine is the user’s Access Code tones. The HWI-TEL9 is listening in and when the answering machine plays this message, the HWI-TEL9 hears this as a valid code, picks up and disconnects the answering machine.

If this happens, the following can be performed to inhibit the HWI-TEL9 from picking up. Hang up, wait at least 1 minute to allow the HWI-TEL9 and answering machine to reset, and then call back. When the answering machine gets to the message that plays the Access Code tones, press random buttons on the telephone. This will cause the HWI-TEL9 to see an incorrect Access Code and not pick up the line and disconnect the answering machine.