Line Sense Relay

This Line Sense Relay addresses telephony hook switch monitoring and rotary dial pulse counting while addressing regulatory needs.

M-949-11 Balanced Dual Coil Telephone Line Current Sensing Relay (Data Sheet)

• Senses telephone line current from 15 to 200mA
• Used by control circuitry for on-hook/off-hook monitoring, switch hook flash detection and rotary dial pulse
• Meets high isolation voltage requirement of 4000V
• Meets UL and British Standard specifications
• Includes 1 Form A relay contact

AN-142: M-949 - Loop Current Sensing and Ring Chatter

Block Diagram