Black Box 5000 manual 244

Multiserver 5000

LL RT SI RD TD

Figure E-5. CSU/DSU Module Indicator Positions.

Table E-5. CSU/DSU Module Indicators

LED	Indicator
Indicator	Definition	Off	Flashing	On
LL	Local Loopback	Normal operation	Local Loopback Test	---
			is active
RT	Remote Terminal	Normal operation	Digital Loopback or Remote	---
			Terminal Loopback Test is
			active
SI	Status Indicator	Power is off or	CSU/DSU is receiving	Power is on and
		module is defective	out-of-service signals from	CSU/DSU is
			code, or out-of-frame DDS	synchronized with
			code, or no DDS signal	the network
			is being passed
RD	Received Data	No data is being	CSU/DSU module is	CSU/DSU module
		received by the	receiving error during	is receiving data
		CSU/DSU module	Test Pattern Test
TD	Transmitted Data	Not data is being	Data is being	Data is being

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