3M Dynatel 900 Series User manual

DynatelTM
900/900M Series
Test Set
Operators Manual
September 1996
78–8093–0453–4 Revision D
Advanced Test Equipment Rentals
www.atecorp.com 800-404-ATEC (2832)
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3M Dynatel 965 Specs
Provided by www.AAATesters.com

DynatelTM
900/900M Series
Test Sets
Operators Manual
The information in this manual is proprietary to 3M
and may not be reprinted or otherwise copied without
the express written permission of 3M.
1996 Minnesota Mining & Manufacturing Company

Page i
Table of Contents
Section One – Operation
1. INTRODUCTION 1. . . . . . . . . . . . . . . . . . . . . . . . . .
2. 900/900M SERIES TEST SETS 4. . . . . . . . . . . . .
Notes on Using the Test Set 4. . . . . . . . . . . . . . . . .
3. AUTO CAL 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A. Charge Battery 5. . . . . . . . . . . . . . . . . . . . . . . .
B. Self Calibration 5. . . . . . . . . . . . . . . . . . . . . . . .
C. Access 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D. Battery Type 6. . . . . . . . . . . . . . . . . . . . . . . . . . .
E. Identification 6. . . . . . . . . . . . . . . . . . . . . . . . . . .
F. Custom Cable 6. . . . . . . . . . . . . . . . . . . . . . . . .
G. Other Setups 7. . . . . . . . . . . . . . . . . . . . . . . . .
4. DIAL 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DC Line Test 10. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Current 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ohms 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ohms to Distance (Ohms/Ft.) 18. . . . . . . . . . . .
Resistance Fault Locate 20. . . . . . . . . . . . . . . . .
Tone 38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Opens 40. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Splits 44. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AC Line Test 48. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ringers 50. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REG 52. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Loss 54. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Noise 56. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Section Two – Special Applications
1. MULTIPLE RESISTANCE FAULTS 59. . . . . . . . . .
2. WATER IN CABLE - RESISTANCE
FAULTED PAIR 60. . . . . . . . . . . . . . . . . . . . . . . . . .
3. SECTION ANALYSIS 61. . . . . . . . . . . . . . . . . . . . .
4. LOAD COILS 62. . . . . . . . . . . . . . . . . . . . . . . . . . . .
5. LOCATING OPENS BY RATIO 64. . . . . . . . . . . . .
6. LOCATING OPEN SHIELD 65. . . . . . . . . . . . . . . .
7. TEMPERATURE CONVERSION 66. . . . . . . . . . .

Page ii
Section Three – Specifications
2. 955/955M COMBINATION FAULT LOCATOR 67
A. Measurements 67. . . . . . . . . . . . . . . . . . . . . . . .
B. Resistance Fault Locate 67. . . . . . . . . . . . . . .
C. Outputs 69. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D. Environment 69. . . . . . . . . . . . . . . . . . . . . . . . . .
E. Dimensions 69. . . . . . . . . . . . . . . . . . . . . . . . . .
F. Battery Power 69. . . . . . . . . . . . . . . . . . . . . . . .
3. 945/945M SUBSCRIBER LOOP TESTER 70. . .
A. Measurements 70. . . . . . . . . . . . . . . . . . . . . . . .
B. Outputs 71. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C. Environment 71. . . . . . . . . . . . . . . . . . . . . . . . . .
D. Dimensions 71. . . . . . . . . . . . . . . . . . . . . . . . . .
E. Battery Power 71. . . . . . . . . . . . . . . . . . . . . . . .
4. 965/965M SUBSCRIBER LOOP ANALYZER 72.
A. Measurements 72. . . . . . . . . . . . . . . . . . . . . . . .
B. Resistance Fault Locate 73. . . . . . . . . . . . . . .
C. Outputs 75. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D. Environment 75. . . . . . . . . . . . . . . . . . . . . . . . . .
E. Dimensions 75. . . . . . . . . . . . . . . . . . . . . . . . . .
F. Battery Power 75. . . . . . . . . . . . . . . . . . . . . . . .
Section Four – Care and Maintenance
1. TEST LEAD AND BATTERY
INSTALLATION INSTRUCTIONS 77. . . . . . . . . . .
2. BATTERY MAINTENANCE 79. . . . . . . . . . . . . . . .
A. When To Charge or Replace Batteries 81. . .
B. Internal Battery Charging 81. . . . . . . . . . . . . . .
C. External Battery Charging 81. . . . . . . . . . . . . .
3. CHECK OPENS PERFORMANCE 82. . . . . . . . . .
4. CHECK RESISTANCE FAULT LOCATE
PERFORMANCE 83. . . . . . . . . . . . . . . . . . . . . . . . .
Appendix–Generally Accepted Criteria
for Standard Telephone Service Appendix 1. . .

Page iii
This manual is being issued to reflect the 900 seires and
900M series test sets in one manual. This manual includes
additional information and corrections to the previous
versions including (but not limited to) some organizational
changes to aid in use of this manual.
Comments concerning the contents or organization of this
document, as well as suggestions for improvement are
welcomed. Direct comments to:
3M Telecom Systems Division
Lab-Technical Communications
6801 River Place Blvd.
Austin, TX 78726–9000
For Technical Service call 800/426 8688
(outside the U.S.A. call 512/984 2575)

Page iv
How to Use This Manual
Although your test set may not have all the functions
described here, all the 900 Series test sets tell you what to
do at every step, including where to connect the test leads.
Turn to the tabbed pages for information about each test.
Section One – Operation introduces and describes the
900/900M Series test sets, with operating instructions for
each function. Instructions include descriptions of each
test, hookup instructions, and a step-by-step example of
each test function.
Section Two –Special Applications contains
instructions for locating multiple resistance faults, wet
sections, performing section analysis, compensating for
load coils in cable measurement, some special opens
locating techniques, and temperature conversion.
Section Three – Specifications
Section Four – Care and Maintenance
Appendix – Generally Accepted Criteria for
Standard Telephone Service

Page v
Glossary of Terms
3M 1020B:
Testline for two-way gain/slope or step tone functions.
Access:
Telephone line or circuit connection to test equipment.
Address:
Information specifying a physical location of trunk
termination in a switch, or the logical location of the
trunk termination data in the switch computer.
Analog:
Any system where data is represented by a
continuously variable range of values, such as the
hands of a clock or the needle on a meter.
AWG:
American Wire Gauge. A numerical table designating
the cross-sectional area of wire. The larger the AWG
number, the smaller the wire.
Balance:
The amount of current cancellation along tip and ring
conductors. The subscriber hears non-cancelled
currents as noise metallic. BALANCE (dB) = POWER
INFLUENCE minus CIRCUIT NOISE.
C–Message Weighting:
This filtering makes measurements of noise more like
the response of the human ear to various frequencies
over a telephone circuit. Sensitivity of the ear drops at
frequencies below 800 Hz, and above 2500 Hz.
Central Office (C.O.):
Telephone switching center for connecting calls.
Cursor:
A flashing symbol on a display screen indicating
position for data entry.

Page vi
Database:
All of the information stored in a computer available
for retrieval and updating.
dBm:
A measurement of the power of a signal received
above a reference power of 1 milliwatt (10-3 watts).
dBrn:
(dB reference noise): The reference for noise
measurement, a level equivalent to a tone at –90
dBm. 0 dBrn = –90 dBm and 0 dBm = 90 dBrn.
dBrnC:
dBrn measured with C-message weighting.
Decibel (dB):
A unit for measuring the relative strength of a signal
parameter, such as power or voltage, often used in
measuring loss or gain of power in a device or circuit.
DLL:
Dial Long Line – a loop treatment device to boost the
loop current.
Dial Pulse:
The method of telephone dialing by alternately
opening and closing (pulsing) a contact in the
telephone (dialing the digit 7 produces seven pulses).
Dial Up:
The means of establishing a connection through the
network over public dial ports.
Digital:
Information or graphic data that has been translated
into a discrete numerical value, and therefore can be
manipulated and reproduced without loss of quality.
DTMF:
Dual Tone Multiple Frequency – a touch-tone dial
frequency.

Page vii
Ground Resistance:
The resistance between the subscriber protector
ground and C.O. ground.
Line Loss (Circuit Loss):
Measurement of power loss in dBm, measured with
flat weighting over the voice frequency band.
Loading, Cable:
Adding inductance (load coils) at specific intervals
along a cable to reduce distortion and improve
frequency response, compensating for
transmission-degrading distributed capacitance
between conductors.
Loop Current:
Current in mA required to operate C.O. equipment
and station apparatus at the subscriber premises.
Loop Treatment (REG., DLL, etc.):
This is C.O. extension equipment placed on a pair to
overcome excessive line loss.
Loss:
Decrease in power (dB) of a transmitted signal.
Maintenance Test Unit (M.T.U.):
Device at protector that allows tester to isolate
trouble to premise wiring.
Noise:
Signal producing undesirable sound on telephone
line, caused by impedance discontinuities, crosstalk,
or other interference.
Noise Metallic (Nm):
Noise measured across the tip and ring of a circuit
that the customer actually hears on the line. The
same as circuit noise, measured in units of dBrnC.

Page viii
Power Influence (PI):
Noise measured between ground and the tip and ring
conductors shorted together. Not heard by the
subscriber, the power influence affects the amount of
noise metallic the subscriber hears. The same as
noise-to-ground (Ng), measured in dBrnC.
REG:
Range Extender with Gain (loop treatment) boosts
C.O. battery voltage and amplifies AC speech signal.
Ringers:
The ringer circuit of a subscriber telephone set, wired
tip, wired ring, or bridged. Measured in tenths of a
ringer, allows identification of nonstandard equipment.
Slope:
The rate of change in attenuation relative to
frequency of a transmission line.
Step Tone:
A three - nine frequency tone generator used to
detect loading problems.

SECTION 1
Page 1
Test Set Operation
1. INTRODUCTION
1.1 This manual provides operating instructions for
the Dynatel 900/900M Series test instruments.
The first in the series, the 955 and 955M Combination
Fault Locators performs dead-cable (vacant pair) diagnostic
testing and resistance fault locating as well as opens and
splits test functions and load-coil counting. The 945 and
945M Subscriber Loop Testers combine the 955/955M
functions (except resistance fault locating and splits) with
an active-cable diagnostic routine and its associated tests.
The 965 and 965M Subscriber Loop Analyzers combine all
tests, diagnostic routines, and fault locating capabilities of
the 900/900M Series test sets.

Operation
Section 1
Page 2
The Digital World – Some Differences Between
Analog and Digital Testing
1.2 Each 900/900M Series test set contains a
computer that tests the line and displays the
results. Read the display carefully. The results may look
different and have more information than what you’re used
to.
1.3 Analog meters have relatively low high-resistance
limits; for example, some can read up to 3
Mohms, while others can read up to 30 Mohms. In
comparison, the digital 900/900M Series unit can read high
resistance faults up to 100 Mohms.
1.4 With an analog meter, you have to manually move
the clips from across the pair to ring-to-ground
and tip-to-ground, to determine if the fault is a short or
ground. With just one hookup, the 900/900M Series test set
tests the pair tip-to-ring, ring-to-ground and tip-to-ground.
The unit displays the fault and its value on the display
screen (see example, next page) at the press of a key on the
unit’s front panel.

Operation
Section 1
Page 3
OHMS
AMPERES
D.C.
Leakage path
TIP
RING
Volt/Ohm Meter Display
(Analog Reading)
3 Megohms
SHORT – (High Resistance):
Comparative Displays
of Digital and Analog Readings of a Faulted Pair
900/900M Series Test Set Display
(Digital Reading)
1.5 Other analog meters have converted ohms into
points. The chart on the next page shows
comparative values for ohms and points.

Operation
Section 1
Page 4
OHMS TO POINTS
Ohms Points
0 100
6K 95
11K 90
24K 80
40K 70
67K 60
100K 50
150K 40
230K 30
400K 20
900K 10
2M 5
3M 0
2. 900/900M Series TEST SET
2.1 This section of the operators manual contains
operating instructions for 900/900M Series test set
functions, including descriptions of each available test,
hookup instructions, and step-by-step flowcharts of each
test function.
Notes on Using the Test Set
2.2 DISPLAY – Adjust display visibility by pressing
(up-arrow key) or (down-arrow key) when
the unit is first turned on. If your set is equipped with a
backlight, hold down the (star key) and press the
(left-arrow key) to turn the backlight on and off. For a
900-T series test set, see its accompanying Terminal
Emulation Manual for backlight instructions.
2.3 STORED TELEPHONE NUMBERS – Eight
numbers may be stored under the DIAL key for
general use. Eight numbers each reside under the LOSS

Operation
Section 1
Page 5
key, NOISE key, and in the step tone and 3M 1020B
options under the AC LINE TEST key. To enter a
telephone number, press the DIAL key,LOSS key,or
NOISE key. Press the (star key) to advance to the
SELECT/EDIT screen. Use the arrow keys to move the
cursor, then type the number. Use the OHMS TO
DISTANCE key to erase a number. Press the DIAL key to
store the number. Press the ON/RESET key to escape the
program without dialing.
3. AUTO CAL
3.1 The AUTO CAL key gives you access to the
following maintenance and accessory functions.
Use the up- and down-arrow keys to move the cursor to
your choice, then press the (star) key to activate the
function.
A. Charge Battery
3.2 For rechargeable batteries only, use this option
and follow the displayed instructions to use the
internal battery charger. The unit determines when the
batteries are fully charged and turns itself off automatically.
Warning:
Never try to charge a non-rechargeable battery. Damage to the
battery or personal injury from explosion may result.
B. Self Calibration
3.3 To maintain accuracy, use this option to
self-calibrate the unit every day and during
temperature changes. Press the (star) key to select
SELF CALIBRATION, then short all the test clips
together. Press the (star) key. The unit displays
“PLEASE WAIT” while it self-calibrates, then “beeps”
and instructs you to disconnect the leads and press the
(star) key. When you have disconnected the leads, and

Operation
Section 1
Page 6
made sure they are not shorting against one another, press
the (star) key and wait while the unit performs a RAM
(random-access memory) test. The screen displays “SELF
CALIBRATIONS ARE COMPLETED ✱.” Press the
(star) key to return to the AUTO CAL menu. If the unit
fails self calibration, return it for service. The only
exception may be if the error message is “OPEN TEST
LEAD,” a condition that may be solved by replacing the
test lead assembly. (See the phone number for 3M
Technical Service in the front of this manual.)
C. Access
3.4 ACCESS has no user function. If you select this
option, press the Reset key to continue.
D. Battery Type
3.5 To control charging, the unit must know what type
batteries it contains. Select this function, then
press either the (star) key for rechargeable
nickel-cadmium batteries, or the (pound) key for dry
cells (alkaline batteries).
3.6 To replace the batteries, refer to Section Four,
“Care and Maintenance” in this manual.
E. Identification
3.7 This function displays the unit’s model, serial,
version, and terminal identification numbers.
Press the (star) key to return to the menu.
F. Custom Cable
3.8 Use this option to program cable capacitance into
the unit for use on non-standard cables. Type the
mutual and tip-ground capacitances as requested. You will
use these cable specifications when you select the
CUSTOM CABLE option from the CABLE TYPE menu
in the OPENS test routines.

Operation
Section 1
Page 7
3.9 To determine a cable’s capacitance, press the
OPENS key. Press the (star) key to select
NORMAL MODE, then wait. When the display changes,
press the (pound) key to call up the OPENS menu.
Move the cursor to CALIBRATE TO CABLE and press
the (star) key. The display tells you to connect the black
and red leads to a reference pair of known length in the
cable, and connect the green lead to grounded shield. You
must be hooked up to a non-standard cable of known
length. Press the (star) key, then enter the length and
press the (star) key again. The unit displays the
calibration results. Press the AUTO CAL key and follow
the instructions in para.  above, to program the
capacitance under the CUSTOM CABLE option.
G. Other Setups
3.10 Use this option to control the sound of the
keystroke “beeps.” For the 900-T series test
sets, use this option to setup the real-time clock and view
the log which shows information about the last time the
set was on the battery charger.
3.11 To setup the clock, use the arrow key to move the
cursor next to the “setup clock” option, and press
the (star key). Use the arrow keys or numeric keypad
to edit the number. Enter the time by pressing the (star
key). Next, use the arrow keys or numeric keypad to edit
the date. Enter the date using the (star key).
3.12 To view the battery-charge log, use the arrow key
to move the cursor next to the “xxxxxxx” option,
and press the (star key). The battery-charge log shows
the beginning and ending dates and times of the last
charging. The first charging voltage and current are
displayed, along with the percentage of charge capacity and
the bettery voltage before the charging cycle begins.

Operation
Section 1
Page 8
4. DIAL
4.1 DIAL lets you connect to a working line, monitor
it for conversation, then dial any number such as
for battery kill, automatic number announcing (ANA),
voice dispatch systems, loss or noise testing, or to listen to
the called party. When the number is dialed, you can press
the LOSS or NOISE keys to start those test routines. The
unit can provide 1-second ring ground (ground start) if
open tip is detected. Some units are optionally equipped to
test for caller I.D. and message waiting.
Example – Dial Number
RED to RING
BLACK to TIP
GREEN to GROUND
Hookup: R
B
G
Use arrow keys to
move cursor; use key
pad to enter number.
Disregard this step
if the unit is on.
Dial type menu
Turn unit on.
Unit monitors
line
End
of
Test
Press # for ground
start, otherwise, press *
Unit dials
number.
On
Reset
DIAL
Use arrow keys to
move cursor to dial
type option.
To dial, go off-hook when
instructed on the display.
Choose touch-tone or dial
pulse. “Manual” allows you to
enter additional access digits.
To select a number on the
screen, line up the cursor with
the number, then press DIAL.
To erase a digit, press the
Ohms to Distance key. In auto-
matic dial mode, move the cur-
sor to the left to type a number
with more than 7 digits.
DIAL
DIAL
When the number is dialed, you
can press the LOSS or NOISE
keys to go directly into those
test routines, or monitor voice.
Listen for dial tone.
OR
OR
OR

Operation
Section 1
Page 9
Example – Caller I.D. Option
RED to RING
BLACK to TIP
Hookup: R
B
Disregard this step
if the unit is on.
Timing and carrier
level parameters
information display
Turn unit on.
Select to dial
or caller I.D.
End
of
Test
On
Reset
DIAL
Unit monitors line,
displays caller I.D.
You can press the * key
to go to number dialing.
Received data
displayed in
hexadecimal format.
The data displayed
includes seizure
characters (hex 55) and
“ - - ” to indicate a
period of about 10 ms in
which no character was
received.
The unit monitors the line for
message waiting signal, and
indicates if the message wait-
ing light is off or on.
OR
OR

Operation
Section 1
Page 10
DC Line Test
RED to RING
BLACK to TIP
GREEN to GROUNDED SHIELD
Hookup: R
B
G
About DC Line Test
Use the automatic DC Line Test routine to evaluate a
vacant pair being placed into service or any pair with
suspected problems.
Attach the leads, then turn the unit on.
Always verify results with appropriate manual tests (blue
keys) before taking corrective action.
Caution
If hazardous voltage warnings are displayed when the test set is
switched on or reset (or at any time during the testing procedure)
follow standard procedures for de-energizing and discharging
cables.