ASL INTERCOM VAR4 - Page 61

VAR4 / VAR12 / VAR20 - Operation Manual
Is
Page 61 of 308
sue: 03 complete, approved
6. Scroll the surveillance frequency range until the required option is displayed:
[No Surv]
• No Surv
No AC surveillance.
This setting is used when the Amplifier Interface Card does not provide AC surveillance, e.g., the
ASL NSINT Non-Surveyed Interface Card.
• LF Surv
Low frequency surveillance.
This setting is used when the Amplifier Interface Card uses a low frequency surveillance tone in
order to monitor the connected amplifier, e.g. the ASL interfaces cards:
− LSDDC Dual DC Line Surveillance Interface Card with Loop Return Option
− LSDIC Line Sensing Direct Current Interface Card
− SSINT Standby Interface Card
• HF Surv
High frequency surveillance.
This setting is used when the Amplifier Interface Card uses a high frequency surveillance tone in
order to monitor the connected amplifier, e.g. the ASL LSDIC Line Sensing Direct Current Interface
Card used in customised high frequency applications. Please refer to Application Solutions Limited
for further details.
Default values: ‘No Surv’
Note: If surveillance is enabled, ensure that the VAR Router output connected to the amplifier being
configured is set to generate the surveillance tone, as described in Section “12.4 Surveillance
Tone Generation Configuration”.
7. Commission the amplifier by pressing the SELECT key, or cancel by pressing the BACK key.
The system will return to the parent menu after 3 seconds on pressing the SELECT key, or immediately
on pressing the BACK key.
Note: If ‘LF’ or ‘HF’ has been selected, configure the other AC surveillance parameters, as described
in the following sections for correct fault reporting.