FAULT REPAIR PROCEDURES

Note: When performing loop-back connection tests on the trunks at the user’s office, provide cross connection as follows:

ATTENTION

Contents

Static Sensitive

Handling

Precautions Required

(1) For a COT

A

LC

C O T

 

 

C

LC

 

B

LC

 

 

 

Set up a loop-back connection between the COT (C.O. Trunk) to be tested and station line.

The trunk route must be assigned for Loop Start.

(2)For a TLT (for DID)

A

LC

T LT

B

LC

T LT

Set up a loop-back connection between the Tie Line Trunk (TLT) to be tested and another TLT.

If the TLT is a Direct Inward Dialing (DID) Trunk, connect the related leads as shown below:

TLT

T T

R R

TLT

If the TLT is a 4-wire E & M System, connect the related leads as shown below:

TLT

Receive

Send

T T

R R

T T

R R

E E

M M

Receive

Send

TLT

NDA-24300CHAPTER 5

Page 327

Issue 1

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NEC NDA-24300 manual Tlt