User guide

6-18 Encore Multi-port DSU/CSU User GuideÑJuly, 1997

¥ Make sure the network carrier is using the ANSI T1.403 or AT&T TR54016 protocol.

The system does not respond to any other ESF protocols.

¥ If the above steps fail to solve the problem, call Digital Link technical support for

assistance.

Current Tests Terminate without your Intervention

¥ Make sure the system is set to run the test for an unlimited amount of time.

Test length options are 15 min., 1 min., 60 min., Unlimited.

With Self Test, Loop Up Remote and Loop Down Remote, Unlimited does not apply.

¥ If the above step does not correct the problem, call Digital Link technical support for

assistance.

The System Cannot be put into Network Loopback from the Carrier

¥ Make sure the network carrier is sending a standard framed network loop up code

of 10000 to the system.

¥ Make sure the system is set to receive the same standard or alternate code as the

network.

¥ Using your T1 test set, send a loop up code into the system. If the system still does

not loop up, call Digital Link technical support for assistance.

The System cannot be Put into Payload Loopback from the Network

¥ Make sure the system is set for V.54 fractional loopback code, if the network is

sending V.54 to loop it up.

¥ Make sure the payload portion you are attempting to loop up has assigned

bandwidth.

¥ If the DSU/CSU still does not loop up, use your T1 test set to inject a fractional

loopback signal on the channels you want to test.

¥ If the above steps fail, call Digital Link technical support for assistance.