8851 with KEM module line busy detection

[yun zhang]

Hi Guys 

An operator line with key expansion module that she need transfer call from PSTN by KEM module, how to detect the line busy status in the KEM module when a call from PSTN and operator doesn't know line status who would be transfer? 

Harvey Zhang

[Dan Lukes]

Wrong forum. 8851 is not Small Business kind of product. Moved.

[Jonathan Schulenberg]

Assuming CUCM since you didn’t specify.
Busy Lamp Fields will display a red LED state when that Directory Number has an active call.
https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/admin/9_0_1/ccmfeat/CUCM_BK_CEF0C471_00_cucm-features-services-guide-90/CUCM_BK_CEF0C471_00_cucm-features-services-guide-90_chapter_0101110.html