
Hardware Installation
DP LINE 1
DP LINE 2
P LED Indicator
•Indicates U interface status connection.
•Controlled by 
•When U interface and S/T interface are NOT active, LED remains off.
•Flashes 8 times/second (8 
•Flashes once/second (1 
•Lit, not 
D LED Indicator
•Lights when the ISIHP-2S/2U  is turned on.
•Flashes until SPIDs are verified with the central office switch; then remains lit without flashing.
•Indicates data link layer status.
MultiModemISI Hybrid Series,   | 11  |