Toshiba Strata Dk14, Dk40i, Dk424 Installation And Maintenance Manual

DK424 T1
Applications
Strata DK I&M    5/996-11
DK424 T1
 Applications
Each RDTU T1 PCB requires the following connecting equipment and cables to provide service  
(see the following sections and Figure 6-4).
RDTU to Network
If the RDTU must interface to a public telephone network or common carrier T1 circuit, the 
RDTU must be connected to a CSU. Use the NDTU cable (30 ft. cable supplied with RDTU) to 
connect the RDTU to the CSU. The function of the CSU is to provide the required interface 
between the...

DK424 T1
Applications
6-12Strata DK I&M    5/99
RDTU to PBX T1 (Separated Less Than 655 ft.)
If the RDTU is within 655 ft. of the far-end PBX T1 circuit, a CSU is not required. However, 
connecting a RDTU T1 span to another PBX or Key/Hybrid T1, in a Tie line configuration at a 
distance less than 655 ft. (without a CSU) will require a customer provided special cable. The 
transmit and receive pair of this span cable must be separated by at least five cable pairs and the 
wires must be 24 AWG, twisted...

DK424 T1
Hardware and Cabling
Strata DK I&M    5/996-13
DK424 T1
Hardware and Cabling
RDTU Cable Length Switch
The distance between the DK424, RDTU and CSU or RDTU to other Customer Premise 
Equipment (CPE) T1 may vary (0~655 ft.) as shown. (See Figures 6-4, 6-5, and 6-6.) The RDTU 
interface transmitter must be equalized and its impedance must be matched to the cable length 
connecting the RDTU to the CSU or other CPE, T1. 
RDTU transmit equalization/ impedance matching is accomplished by setting RDTU...

DK424 T1
Hardware and Cabling
6-14Strata DK I&M    5/99
Synchronization LEDs
©Primary Synchronization (PSYNC) LED (see Figure 6-1 on Page 6-6) – If one RDTU PCB is 
assigned as the Primary Timing T1 PCB in Program *42, the PSYNC LED of this RDTU PCB 
flashes when it is synchronized with the far end T1 span line clock provider. If the Primary 
RDTU is not synchronized with the clock provider, the PSYNC LED will be ON steady. The 
SSYNC LED of the Primary sync RDTU PCB should always be OFF. The Primary...

DK424 T1
Hardware and Cabling
Strata DK I&M    5/996-15
DK424 T1
1670
RDTU PCB (26)
(1)
(27)
(2) T
R
T1
R1 Black 
Red
White
Green Customer-supplied Cable (See Notes) RDTU To Customer Premise Equipment (CPE) T1
RDTU Amphenol CPE T1 (PBX 
or Key 
System) or 
Channel Bank
655 Feet MaximumTransmit
Receive (4)  T
(5)  R
(1)  T1
(2)  R1 Network
Interface Unit
USOC-RJ48C
or RJ48X
8-Pin Modular
(RJ45 Type Jack)NDTU DB-15
Connector (Male)
DB-15
Connector (Female) Customer Supplied
Cable (See Notes)RDTU To Network...

DK424 T1
Loop Back Testing
6-16Strata DK I&M    5/99
Loop Back Testing
The RDTU provides three loop back test configurations. These loop back tests should be 
performed as required in conjunction with CSU loop back tests (see CSU loop back test 
documentation).
RDTU Self Test
This test should be performed upon initial installation of a RDTU PCB. Program the RDTU per 
“System Programming for T1” on Page 6-3; then perform the RDTU loop back test, per the 
instructions in Figure 6-8, before connecting the...

DK424 T1
Loop Back Testing
Strata DK I&M    5/996-17
DK424 T1
Network/CSU/RDTU Span Test
This test checks all equipment that is checked with the test in the above paragraph, but this test 
also checks that the RDTU Mitel LSI chip is functioning. Guidelines for this test are described in 
Figures 6-8~6-10.
NoteLoop back tests with CSU and Network equipment can also be performed when 
connecting the RDTU PCB directly to a customer premise (PBX, Key Hybrid, Channel 
bank) T1 circuit.
The RDTU Self Test is...

DK424 T1
Performance Monitoring
6-18Strata DK I&M    5/99
Performance Monitoring
The performance of the RDTU can be monitored using the Data Dump Mode. This requires an 
RSIU, RSIS, PIOU or PIOUS PCB, an ASCII terminal (or PC) and, if monitoring RDTU 
performance from a remote location, an IMDU or RMDS modem or Hayes compatible modem is 
required.
The RDTU monitoring feature provides a printout (or CRT display) of RDTU detected T1 errors 
as shown in Figure 6-10. There are no time parameters given with...

DK424 T1
Performance Monitoring
Strata DK I&M    5/996-19
DK424 T1
Figure 6-10 RDTU Performance Monitor Printout
The error categories are as follows:
©Synchro Bit Error: This counter increments each time the RDTU detects 1024 synchronization 
bit errors.
©Bipolar Violation Error: This counter increments each time the RDTU detects 6.55 x 104 
bipolar violations.
©Slip error: This counter increments each time the RDTU detect 256 slips.
©CRC Errors: Cyclical Redundancy Check counter increments each time the...

DK424 T1
T1 Fault Isolation
6-20Strata DK I&M    5/99
ä
To receive the “T1 ERROR DISPLAY” from a terminal (local or remote)
1. Establish communication with the terminal or PC using a communication software (e.g., 
Procomm®).
2. Enter the security code, and press Enter
 (or Return
).
3. At the >MODE
 prompt, type DUMP
 (must be all caps), press Enter
 (or Return)
. The >D
 
prompt displays on your screen.
4. At the >D
 prompt, type T1ERR
 and press Enter
 (or Return
). The display (see Figure 6-10) 
shows...