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Rev. 11/10/00

17

Testing DSSC, DAML, OR UDC Pair Gain Line

DSSC

DAML

, and 

UDC

 pair gain lines carry approximately 70 to 130 VDC

between the Central Office Terminal (COT) and the Remote Terminal Unit 

(RTU)

located at the subscriber end.  These lines also exhibit Stressed Noise readings of
80 dBrnC and higher in the 

Stress

 test mode.  The excessive voltage on these lines

will not harm the Sidekick but the readings become invalid.  To ensure accurate
readings when testing pair gain lines, follow the simple rules listed below:

1.

 

Be familiar with local procedures when disabling a pair gain system that
serves more than one customer.

2.

 

If local procedures permit, disconnect the C.O. pair from the 

RTU

.  Or, if so

equipped, use the disconnect switch on the 

RTU

 to isolate the C.O. pair.

The line running between the 

COT

 and 

RTU

 will revert to a 

POTS

 line in

approximately 60 seconds.  Perform Sidekick tests as usual.

NOTE

:

Because it is normal for the 

COT

 to transmit a 130 

VDC

 pulse every

one (1) to five (5) minutes, the meter will also pulse.

3.

 

Full path (subscriber to C.O.) testing can be accomplished by disconnecting
and jumping past the 

RTU

.

NOTE

:

Testing pair gain lines from the subscriber side (instrument to 

RTU

)

can be done without disabling or disconnecting the 

RTU

.

Troubleshooting Tips

The closer you are to the source of the trouble, the higher the Stressed Noise

readings will be.  Example:  If a pair exhibits a reading of 40 dBrnC on the F2
distribution at the cross-connect and a reading of 50 dBrnC at the protector/

SNI

,

you can assume that the trouble is closer to the customer premise.  If Stressed
Noise readings decrease (below 50) as you move toward the cross-connect or
beyond the customer’s serving terminal, you can assume that you were closer to
the trouble at the protector/

SNI

.

The Sidekick will read pulses sent across the pair from Maintenance Test Units

(

MTU

s') in the 

Leakage

 test mode.  If this happens, simply set the 

Reverse

 switch

to the opposite position.  

MTU

s' will also create an imbalance on the line when you

test from the customer side.  To compensate, remove the 

MTU 

from the line while

performing the 

Stress

 test from the customer side.

Construction Wire ("C" Rural) will produce high Stressed Noise readings (50+

dBrnC).  In this case, simply verify that the wire reads the same at both ends.
The following examples illustrate some typical faults. Readings of 30 dBrnC at the
cross-connect are taken with the jumper in place.  Readings given for the C.O., F1,
and F2 are taken with the jumper disconnected.  All readings are in dBrnC units.

Summary of Contents for Sidekick 7B

Page 1: ...Tempo Sidekick 7B and T N Training Course Revision 1 03 This manual is for training purposes only 7B Model T N Model...

Page 2: ...d a highly trained and experienced technician place more emphasis on how paramount a thorough understanding of the following principles and analytical procedures are to Finding a better way to trouble...

Page 3: ...ns 5 Shorts 5 Grounds 5 Resistance Faults 5 Noise 5 Line Imbalance 5 Crosses 6 Splits 6 Power Influence 6 Induction 6 Circuit Loss 6 Loop Current 6 SIDEKICK 7B 7 General Description 7 Features 7 Benef...

Page 4: ...etect Test 32 Loop Current Test 33 Power Influence Test 34 Circuit Noise Test 34 Circuit Loss Test 35 QUIZ 4 37 EXAM 2 39 QUIZ EXAM ANSWERS 41 TROUBLE SHOOTING INSIDE WIRING 42 Testing for Good Ground...

Page 5: ...d be determined from their capacitive discharge The practice of Kicking the pair was greatly enhanced by two of the Sidekick s most powerful troubleshooting features the Leakage Test and the patented...

Page 6: ...used After approximately forty five hundred of these were produced the next generation of Sidekicks began to arrive the Sidekick 7B The Sidekick 7B In 1993 the Sidekick received a complete face lift...

Page 7: ...ll Operational Center RBOC in 1998 and has become even more popular than the Sidekick 7B The VIP Sidekick In the early part of 2000 the Sidekick evolved into the Virtual Instrument Package VIP Sidekic...

Page 8: ...gauge increases the diameter decreases and the resistive and capacitive characteristics of the wire to electrical flow increase Temperature humidity and other factors affect the properties of copper...

Page 9: ...hms Law Ohms Law is a formula used to calculate voltage current and resistance when any two of these values are known The formula is expressed in three different variants depending upon which values a...

Page 10: ...the result from a magnetic field that surrounds a wire when current flows through the wire The number of turns in the coil and the rate of the change of current through the coil determines the induct...

Page 11: ...d connection Erroneous test readings may occur when a good ground is not present Verify that the test connections are good before starting a test Make sure the test lead clips are securely connected t...

Page 12: ...divert onto another path The affect on service depends on the severity of the short A short can occur when other faults are present Grounds A ground usually takes current or a signal out of the loop i...

Page 13: ...on from AC circuits and other telephone wires Induction from AC circuits usually imparts an audible hum on the line Cross talk is caused by the induction from other telephone lines In a well balanced...

Page 14: ...ressed as a result of a 90 dBrnC longitudinal excitation This test determines the capacitive and series resistance balance characteristics of a twisted pair at any point along the pair It is capable o...

Page 15: ...ce faults masked by galvanic corrosion measures resistance with mid scale red at 1 000 000 ohms performs capacitive Kick RX1K Measures resistance with mid scale red at 100 000 ohms performs capacitive...

Page 16: ...three reasons 1 DC power is required to make a POTS line work 2 DC Volts indicates CO battery presence 3 DC should not be found on a Dry Vacant or Nonworking line Dry Vacant and Nonworking all mean t...

Page 17: ...c 48 52 Vac 4 The red test lead is connected to the Ring wire in a pair and the black wire is connected to the Tip wire T F 5 To switch from AC Volts to DC Volts the Reverse switch is used T F 6 When...

Page 18: ...the REV switch to the DOWN position b use the DC Volts test and hold the Tip switch UP c use the AC Volts test and hold the Tip switch UP d use the AC Volts test and hold the Ring switch UP 10 With th...

Page 19: ...re connected and the line is balanced If the Tip or Ring test lead is disconnected during testing or the line is unbalanced the tone becomes audible and increases as line imbalance increases Nonworkin...

Page 20: ...this test No damage to the test set will occur however readings will be incorrect 1 Turn the MODE SWITCH to the OFF position 2 Connect test leads Black Red and Green to Tip Ring and Ground 3 Turn the...

Page 21: ...est Evaluation Scales to determine pair quality FEET FEET The following Noise Metallic readings as a general rule may be used as a guide to determine pair quality Stress Test Measured in dBrnC Scale 0...

Page 22: ...ervice area The closer a pair is to or below the relative reading the better its performance When performing comparison testing a 10 dBrnC or greater difference between pairs indicates trouble on the...

Page 23: ...is Questionable Cables As a cable deteriorates the Stressed Noise readings on all pairs will begin to rise To reduce repeat service calls use the pair with the lowest reading Equipment Balance The Str...

Page 24: ...bscriber side instrument to RTU can be done without disabling or disconnecting the RTU Troubleshooting Tips The closer you are to the source of the trouble the higher the Stressed Noise readings will...

Page 25: ...Rev 11 10 00 18 1 Trouble in C O 2 Trouble in F1 3 Trouble in F2 4 Trouble Isolation in F2 5 Trouble Hi Resistance Open in Drop 6 Trouble in F2 Beyond Sub...

Page 26: ...tone to warn the customer of a test 3 The Stress test drives current through any series resistance on the pair T F 4 At the fault longitudinal current is converted into a a simplex tone b a metallic...

Page 27: ...the Sidekick gets closer to the fault the readings on the meter when in the Stress test will a increase b decrease c fluctuate rapidly 10 In order for the Stress test s simplex tone to be inaudible t...

Page 28: ...sition 2 Connect test leads Black Red and Green to Tip Ring and Ground 3 Verify that the REV SWITCH is toggled to the UP position 4 To test Tip to Ring turn the MODE SWITCH to LEAKAGE RX10K Then wait...

Page 29: ...und NOTE The following Rx selections represent the resistance value in ohms on the meter s red scale A Rx 1 for meter readings up to 1 000 ohms B Rx 1K multiplies meter readings by 1 000 C Rx 10K mult...

Page 30: ...qual kick should be observed Allow the meter to settle between kicks A very large kick indicates ringer presence 5 To kick Tip to Ground Hold the TIP SWITCH UP and toggle the REV SWITCH while observin...

Page 31: ...side only the shorter side will produce an accurate reading For an accurate length measurement use an Open Locator Note Any Series Resistance at the fault will cause the distance to appear longer tha...

Page 32: ...When reading the scale in the Leakage test the resistance reading should be multiplied by 10 000 to determine the Leakage value T F 5 Resistance values are read using the black scale on the Sidekick m...

Page 33: ...or s a height b length c depth d gauge 9 When using the Sidekick as a Kick meter which meter scale is used a black b red 10 In the RX10K mode each point on the scale represents approximately what dist...

Page 34: ...00 3 How many feet per point of Kick are shown when in the RX10K Leakage mode a 50 b 500 c 5 000 d 10 000 4 Which of the following test functions is used to measure the longitudinal balance of a pair...

Page 35: ...0K mode a Red b Black 10 The REV switch is used to Kick the pair under test T F 11 Which of the following tests uses a 90dBrnC longitudinal signal a Resistance test b Stress test c Kick test d Loop Cu...

Page 36: ...bove 17 Except for Inside wiring how much cable beyond the fault is needed on a single conductor fault to ensure a good reading a none b 10 000 feet c 5 000 feet d 1 000 feet 18 In the Stress test a g...

Page 37: ...Current on working lines troubleshoots low Loop Current Holds connection on C O dial in lines when switching between Circuit Loss Circuit Noise and Power Influence tests Uses audible tone and automati...

Page 38: ...fies up to four load coils on a pair Loop Current Measures a circuit s loop current read out is in milliamps mA on the meter s black scale PWR Influence Power Influence Measures the AC induction level...

Page 39: ...re performing Coil Detection NOTE It is highly recommended that the CO battery be disconnected when using the Coil Detection feature Some CO battery and office connections can mask one or all coils fr...

Page 40: ...decreases and as loop current increases resistance decreases Procedure 1 Turn the MODE SWITCH to OFF DIAL 2 Connect test leads Black Red and Green to Tip Ring and Ground 3 For Tip to Ring Turn the MO...

Page 41: ...Power Influence levels Each black hash mark equals 2 dBrnC NOTE The Sidekick T N will hold line connection when switching between Power Influence and Circuit Noise Therefore switching to Circuit Noise...

Page 42: ...30 dBrnC NOTE If Power Influence is greater than 60 dBrnC subtract Circuit Noise from Power Influence to obtain Circuit Balance Per Bellcore standards Specific company or local standards may be diffe...

Page 43: ...he frequency generator test number sends slope sweep or selected frequencies leave the test set in the CKT LOSS position Each change in frequency will produce an audible tone that registers on the met...

Page 44: ...s the amount of noise present a across Tip and Ring b from Tip to Ground c from Ring to Ground d from Sheath to Ground 4 An acceptable Circuit Noise level would be a 30 to 50 dBrnC b 0 to 20 dBrnC c 0...

Page 45: ...below 20 mA b 20 23 mA c 23 mA and higher d None of the above 9 In the Load Coil test a needle dip from the far right to about 50 indicates that a load coil was detected T F 10 The maximum number of...

Page 46: ...ick T N multicolored scale a in the blue zone b in the red zone c in the yellow zone d in the green zone 4 An acceptable Circuit Noise level would read a 0 to 30 dBrnC b 0 to 20 dBrnC c 20 to 30 dBrnC...

Page 47: ...current is inversely proportional to resistance therefore as resistance increases the loop current measured on a pair a decreases b increases c remains constant d is not affected 10 With multiple load...

Page 48: ...T 1 D 2 A 3 True 4 B 5 False 6 True 7 C 8 D 9 A 10 B 1 True 2 B 3 D 4 True 5 False 6 A 7 C 8 B 9 A 10 B 1 C 2 False 3 A 4 B 5 C 6 True 7 A 8 B 9 True 10 D 1 True 2 B 3 A 4 C 5 True 6 True 7 C 8 A 9 B...

Page 49: ...ining Tip or Ring test lead 2 With the meter still in the STRESS TEST Mode determine the quality of the pair by comparing the meter reading on the black scale to the following Noise Metallic levels St...

Page 50: ...check for old splices staples nails nicking loose connections worn insulation and any new construction Capacitance Testing Kicking the Pair 1 If Resistance Testing failed to detect any faults look for...

Page 51: ...ulated portion of the ground wire 4 Back out the ground clip screw to provide sufficient clearance for the ground wire to wrap around the shank of the screw 5 Lay the wire between the open strain grip...

Page 52: ...nch the test lead down and into the corresponding color marked binding post recess and channel 7 Place the flat washer then the lock washer on the test lead loop 8 Insert and tighten the set screw unt...

Page 53: ...ember to conduct each segment of the Leakage Test for approximately 15 seconds Then run the Stress Test again Q The Stress Test reads 30dBrnC but the pair works fine Why A Check the other working pair...

Page 54: ...e following tests in the following order AC volts DC volts Stress Leakage then return to Stress If these tests read good then the circuit is good If you are using a Sidekick T N you should run the Cir...

Page 55: ...he heating and drying action repeat This repetitive process can continue as long as moisture is present in the cable Q Can I get a shock from the 135Vdc used in the Stress or Leakage Test A You might...

Page 56: ...ong narrow jaws properly named Gharial clip ampere The standard measurement unit of electrical current flow amperage The amount of electrical current flow amplification The process by which the output...

Page 57: ...nductive interconnecting device Caller ID on Call Waiting A service feature that delivers calling number and or calling name information for an incoming Call Waiting call capacitance The property of a...

Page 58: ...of 90 dBrn as measured with a noise meter and weighted by a frequency function called C Message weighting dc or DC Direct current dc preferred Electrical current that flows in one direction dielectri...

Page 59: ...usually expressed in micro or picofarads fault A condition that causes a device a component or an element to fail to perform in the required manner e g shorts opens etc fault tolerance The capability...

Page 60: ...computers and peripherals in a limited area leakage A loss of energy when an electrical current travels to a path other than its intended one manhole A utility access hole large enough to provide acc...

Page 61: ...le Early cable with paper insulated wires The insulation was formed directly from wood pulp pulse A short signal duration characterized by rapid amplitude change pulse TDR A Time Domain Reflectometer...

Page 62: ...split When an input signal is distributed to several outputs Spit Pair A splicing error between two pairs of wire where the wire on one pair is connected to the wire of the other pair splitter A circu...

Page 63: ...and or the ground from the CO battery token ring The use of a token to control access in a token ring network tone A single frequency audio signal usually used as a reference tone generator A device t...

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