Dynatest 1295 User manual

Dynatest 1295 Version 1.07i Sep 2017
1295 PAVEMENT FRICTION TESTER
OPERATION MANUAL
Version 1.07
Dynatest North America, Inc.
11415 Old Roswell Road Suite 100
Alpharetta, Georgia USA
PHONE: [phone]
FAX: [phone]
E-mail: [e-mail]
Dynatest®

Dynatest 1295 Version 1.07 ii Sep 2017
TABLE OF CONTENTS
SECTION DESCRIPTION PAGE
Section 1 Introduction
1.1 Introduction .....................................................................................1
1.2 Model 1295 System Description.......................................................1
1.3 Principles of Operation.....................................................................1
1.4 Daily Start-up Procedures................................................................3
1.5 Model 1295 Electrical Systems Components....................................4
1.5.1 Control Console ................................................................4, 5, 6
1.5.2 Portable Computer ............................................................7
1.5.3 Embedded Data Acquisition System .................................7
1.5.4 Operator Pendant Push Button Control .............................7
1.5.5 Printer................................................................................7
1.5.6 Vehicle Speed Display Meter.............................................7
1.6 Tow Vehicle Rear Bed Components.................................................8
1.6.1 250/300 Gallon Baffled Water Tank ...................................9
1.6.2 12 Volt DC Battery ............................................................9
1.6.3 750 Watt Power Inverter ....................................................9
1.6.4 Inverter Bracket..................................................................9
1.6.5 12 Volt DC Air Compressor................................................9
1.6.6 Air Preparation Unit ...........................................................9
1.6.7 External Retractable AC Power Cord.................................9
1.6.8 Four-Way AC Outlet Box....................................................9
1.7 Tow Vehicle Underside.....................................................................10
1.7.1 Positive Displacement Water Pump...................................10
1.7.2 Water Tank Dump Valve ...................................................10
1.8 Tow Vehicle Rear Bumper ...............................................................11
1.8.1 Continuously Adjustable Ball Hitch.....................................11
1.8.2 Water Hose Quick Disconnect ...........................................11
1.8.3 Signal Cable ......................................................................12
1.8.4 Power Cable .....................................................................12
1.8.5 Air Hose Quick Disconnect ................................................12
1.9 Two Wheel Trailer Components.......................................................13
1.9.1 Single/Dual Model 1270 Two-Axis Force Transducer(s).....14
1.9.2 Digital Encoders ................................................................14
1.9.3 Laminar Flow Water Nozzle(s)...........................................14
1.9.4 Power Disc Brakes.............................................................14
1.9.5 Brake Actuator Units..........................................................14
1.9.6 Test Brake Pressure Regulator..........................................14
1.9.7 Electric Lift Jacks...............................................................15
1.9.8 Electric Lift Jack Raise/Lower Switch.................................15
1.9.9 Rear Trailer LED Lights......................................................15
1.9.10 Air Shocks..........................................................................15
Section 2 Calibration
2.1 Calibration menu..............................................................................16
2.2 Force Transducer Calibration...........................................................17
2.2.1 How to perform the Daily Force Transducer(s) Calibration ....17

Dynatest 1295 Version 1.07 iii Sep 2017
TABLE OF CONTENTS
SECTION DESCRIPTION PAGE
Section 2 2.2.2 Editing the Transducer Platform Calibration Values...............18
2.2.3 The Two types of Force transducer(s) Calibrations................18
2.2.4 Understanding How Friction is Calculated .............................18
2.2.5 How often Should the Force Transducer(s) be Calibrated .....19
2.2.6 Description of All Force calibration Fields..............................19
2.2.6.1 View.........................................................................19
2.2.6.1.1 Un-calibrated ..........................................19
2.2.6.1.2 Calibrated ...............................................19
2.2.6.2 Calibrated Values ....................................................19
2.2.6.2.1 Traction Calibration.................................19
2.2.6.2.2 Load Calibration......................................19
2.2.6.2.3 Trailer Weight..........................................19
2.2.6.2.4 Traction Gain..........................................20
2.2.6.2.5 Load Gain...............................................20
2.2.6.2.6 Traction Offset ........................................20
2.2.6.2.7 Load Offset.............................................20
2.2.6.3 Calibration Resistors................................................20
2.2.6.4 Calibration Status ....................................................20
2.2.6.5 Calibrate Button.......................................................20
2.3 Distance and Velocity Calibration.....................................................21
2.3.1 How to Perform Automatic Distance and Speed Calibration 21
2.3.2 How to Manually Enter a Distance & Speed Calibration Value22
2.3.3 How Often Should the Distance & Speed be Calibrated.........22
2.3.4 What Happens if the Distance & Speed Values are Incorrect.22
2.3.5 How Does Distance and Speed Calibration Function .............22
2.3.6 Description of the Distance Calibration Fields ........................23
2.3.6.1 Distance Calibration Length......................................23
2.3.6.2 Right Wheel Encoder Calibration Value....................23
2.3.6.3 Left Wheel Encoder Calibration Value ......................23
2.3.6.4 Vehicle Encoder Calibration Value...........................23
2.3.6.5 Calibration Status Box..............................................23
2.3.6.6 Calibration Button.....................................................24
2.3.6.7 Distance Traveled.....................................................24
2.3.6.8 Left Encoder Count...................................................24
2.3.6.9 Right Encoder Count ................................................24
2.3.6.10 Vehicle Encoder Count.............................................24
2.3.6.11 Left Calibration Value ...............................................24
2.3.6.12 Right Calibration Value.............................................24
2.3.6.13 Vehicle Calibration Value..........................................24
2.3.6.14 Last Calibration Value...............................................24
2.3.6.15 Left Timer Count.......................................................24
2.3.6.16 Right Timer Count.....................................................25
2.3.6.17 Vehicle Timer............................................................25
2.3.6.18 Left Wheel Speed.....................................................25
2.3.6.19 Right Wheel Speed...................................................25
2.3.6.20 Vehicle Speed ..........................................................25

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SECTION DESCRIPTION PAGE
Section 2 2.4 Temperature Sensor Calibration .......................................................26
2.4.1 Temperature Sensor Calibration..........................................26
2.4.1.1 Air Temperature................................................26
2.4.1.1.1 Gain.............................................26
2.4.1.1.2 Offset...........................................27
2.4.1.2 Surface Temperature.........................................27
2.4.1.2.1 Gain.............................................27
2.4.1.2.2 Offset ...........................................27
2.4.1.3 Tire Temperature...............................................27
2.4.1.3.1 Gain.............................................27
2.4.1.3.2 Offset ...........................................27
2.5 Flow and Level Sensor Calibration....................................................28
2.5.1 Flow Meter and Sensor Calibration......................................28
2.5.1.1 Flow Meter 1......................................................28
2.5.1.1.1 Gain.............................................28
2.5.1.1.2 Offset...........................................28
2.5.1.2 Flow Meter 2......................................................28
2.5.1.2.1 Gain.............................................28
2.5.1.2.2 Offset ...........................................29
2.5.1.3 Water Tank Sensor............................................29
2.5.1.3.1 Gain.............................................29
2.5.1.3.2 Offset...........................................29
2.6.1 How to Use the Meter and DAC Calibration ...................................30
2.6.2 Meter DAC Field Descriptions .............................................31
2.6.2.1 DAC 1 –Speed DVM........................................31
2.5.2.1.1 Gain.............................................31
2.5.2.1.2 Offset...........................................31
2.6.2.2 DAC 2 –Left Load DVM ...................................31
2.5.2.2.1 Gain.............................................31
2.5.2.2.2 Offset...........................................31
2.6.2.3 DAC 3 –Right Load DVM.................................31
2.5.2.3.1 Gain.............................................31
2.5.2.3.2 Offset...........................................31
Section 3 Setup
3.1 Initial Setup of the Tow Vehicle and Trailer.......................................32
3.2 Initial Setup of the Computer For Testing .........................................33
3.3 General Software Organization ........................................................34
3.4 Software Setup Process Outline.......................................................36

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Section 4 Operation
4.1 Test Information Menu......................................................................37
4.1.1 Editing Information.................................................................38
4.1.2 Loading Default .....................................................................38
4.1.3 Recalling a Template.............................................................38
4.2 Settings............................................................................................39
4.2.1 Control Parameter Overview.................................................40
4.2.1.1 Test Type........................................................................40
4.2.1.1.1 Standard ...........................................................40
4.2.1.1.2 Chirp .................................................................40
4.2.1.1.3 Target Speed ....................................................40
4.2.1.1.4 Speed Range....................................................40
4.2.1.1.5 Test Suspension Speed ....................................40
4.2.1.2 Test Cycle Sequence......................................................40
4.2.1.2.1 Manual..............................................................41
4.2.1.2.2 Auto ..................................................................41
4.2.1.3 Test Wheel Sequence ....................................................41
4.2.1.3.1 Left....................................................................41
4.2.1.3.2 Right..................................................................41
4.2.1.3.3 Alternate (L-R)...................................................41
4.2.1.3.4 Alternate (R-L)....................................................41
4.2.1.4 Test Start.......................................................................42
4.2.1.4.1 Start Test by Pendant at DMI Start....................42
4.2.1.4.2 Start Test by Pendant after DMI........................42
4.2.1.4.3 Start Test on Distance From DMI ......................42
4.2.1.4.4 Auto Test Start Distance....................................42
4.2.1.5 Test Stop.......................................................................42
4.2.1.5.1 Pendant.............................................................42
4.2.1.5.2 Distance............................................................42
4.2.1.6 Test Time Parameters ...................................................43
4.2.1.6.1 Time parameter 1..............................................43
4.2.1.6.2 Time Parameter 2..............................................43
4.2.1.6.3 Time Parameter 3..............................................43
4.2.1.6.4 Time Parameter 4..............................................43
4.2.1.6.5 Time Parameter 5..............................................43
4.2.1.7 DMI –Distance Measuring Instrument ...........................43
4.2.1.7.1 DMI (Units).........................................43
4.2.1.7.2 DMI Starting Distance.........................43
4.2.1.7.3 Count UP or Down..............................43
4.2.1.8 Miscellaneous...............................................................
4.2.1.8.1 System Units..............................................................44
4.2.1.8.1.1 US/English .....................................................44
4.2.1.8.1.2 Metric.............................................................44
4.2.1.9 Test Watering ................................................................44
4.2.1.9.1 Wet ...................................................................44
4.2.1.9.2 Dry....................................................................44
4.2.1.9.3 Pre-wet..............................................................44

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Section 4 4.2.1.10 Data Average Filter..............................................44
4.2.1.11 Display Settings…………………………………….45
4.2.1.11.1 Speed...............................................45
4.2.1.11.2 DMI...................................................45
4.2.1.11.3 SN....................................................45
4.2.1.11.4 SN Display Value..............................45
4.2.1.12 Cycle Options......................................................45
4.2.1.12.1 Water Control Options......................45
4.2.1.12.2 Nozzle control Options......................45
4.2.1.12.3 Air Compressor Options ...................45
4.2.1.13 GPS Settings.......................................................45
4.2.1.13.1 GPS Bearing ....................................45
4.2.1.13.2 GPS Coordinate display ...................46
4.2.1.14 ROW Camera Settings........................................46
4.2.1.14.1 Mounted upside down.......................46
4.2.1.14.2 Image Inspector................................46
4.2.1.14.3 Image Inspector Duration..................46
4.2.1.15 Vehicle Dashboard Display Settings....................46
4.3.1 Trend Graph Description....................................................47
4.3.2.1 Trend Chart Field Definitions ..........................................48
4.3.2.1 SN Interval –Friction Trend Chart .......................48
4.3.2.1.1 SN Average .......................................48
4.3.2.1.2 SN Max .............................................48
4.3.2.1.3 SN Min ..............................................48
4.3.2.1.4 Y-Scale Min .......................................48
4.3.2.1.5 Y-Scale Max ......................................48
4.3.2.1.6 X-Scale .............................................48

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Section 4 4.3.2.2 SN Interval –Traction Force Trend Chart .............49
4.3.2.2.1 Traction Average ...............................49
4.3.2.2.2 Traction Max .....................................49
4.3.2.2.3 Traction Min ......................................49
4.3.2.2.4 Y-Scale Min .......................................49
4.3.2.2.5 Y-Scale Max ......................................49
4.3.2.2.6 X-Scale .............................................49
4.3.2.2.7 Auto Y-Scale .....................................49
4.3.2.2.8 Manual Y-Scale..................................49
4.3.2.3 SN Interval –Load Force Trend Chart ................49
4.3.2.3.1 Load Force Average ..........................49
4.3.2.3.2 Load Force Max ................................50
4.3.2.3.3 Load Force Min .................................50
4.3.2.3.4 Y-Scale Min .......................................50
4.3.2.3.5 Y-Scale Max.......................................50
4.3.2.3.6 X-Scale .............................................50
4.3.2.3.7 Auto Y-Scale .....................................50
4.3.2.3.8 Manual Y-Scale .................................50
4.3.2.4 SN Interval –Speed Trend Chart ........................50
4.3.2.4.1 Vehicle Speed Average .....................50
4.3.2.4.2 Vehicle Speed Max ...........................50
4.3.2.4.3 Vehicle Speed Min ............................50
4.3.2.4.4 Y-Scale Min .......................................50
4.3.2.4.5 Y-Scale Max.......................................50
4.3.2.4.6 X-Scale .............................................51
4.3.2.4.7 Auto Y-Scale .....................................51
4.3.2.4.8 Manual Y-Scale .................................51
4.3.2.5 SN Interval –Flow Trend Chart ...........................51
4.3.2.5.1 Flow Average ....................................51
4.3.2.5.2 Flow Max ...........................................51
4.3.2.5.3 Flow Speed Min .................................51
4.3.2.5.4 Y-Scale Min .......................................51
4.3.2.5.5 Y-Scale Max.......................................51
4.3.2.5.6 X-Scale .............................................51
4.3.2.5.7 Auto Y-Scale .....................................51
4.3.2.5.8 Manual Y-Scale .................................51
4.3.2.6 SN Interval –Standard Deviation Trend Chart ....52
4.3.2.6.1 Friction SN Standard Deviation .........52
4.3.2.6.2 Traction Force Standard Deviation ....52
4.3.2.6.3 Load Force Standard Deviation .........52
4.3.2.6.4 Vehicle Speed Standard Deviation ....52
4.3.2.6.5 Flow Rate Standard Deviation ...........52
4.3.2.6.6 Y-Scale Min ......................................52
4.3.2.6.7 Y-Scale Max.......................................52
4.3.2.6.8 X-Scale .............................................52
4.3.2.6.9 Auto Y-Scale .....................................52

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Section 4 4.3.2.6.10 Manual Y-Scale...................................52
4.3.2.7 Locking Interval –Friction Trend Chart ...............53
4.3.2.7.1 SN at Peak ........................................53
4.3.2.7.2 SN Max .............................................53
4.3.2.7.3 SN Min ..............................................53
4.3.2.7.4 Y-Scale Min .......................................53
4.3.2.7.5 Y-Scale Max.......................................53
4.3.2.7.6 X-Scale .............................................53
4.3.2.7.7 Auto Y-Scale .....................................53
4.3.2.7.8 Manual Y-Scale .................................53
4.3.2.8 Locking Interval –Traction Trend Chart ..............53
4.3.2.8.1 Traction at Peak ................................53
4.3.2.8.2 Traction Max .....................................53
4.3.2.8.3 Traction Min ......................................53
4.3.2.8.4 Y-Scale Min .......................................54
4.3.2.8.5 Y-Scale Max.......................................54
4.3.2.8.6 X-Scale .............................................54
4.3.2.8.7 Auto Y-Scale .....................................54
4.3.2.8.8 Manual Y-Scale .................................54
4.3.2.9 Locking Interval –Load Trend Chart ...................54
4.3.2.9.1 Load Force Average ..........................54
4.3.2.9.2 Load Force Max ................................54
4.3.2.9.3 Load Force Min .................................54
4.3.2.9.4 Load Force @ Peak ..........................54
4.3.2.9.5 Y-Scale Min........................................54
4.3.2.9.6 Y-Scale Max.......................................54
4.3.2.9.7 X-Scale .............................................55
4.3.2.9.8 Auto Y-Scale .....................................55
4.3.2.9.9 Manual Y-Scale .................................55
4.3.2.10 Locking Interval –Speed Trend Chart ................55
4.3.2.10.1 Vehicle Speed Average....................55
4.3.2.10.2 Vehicle Speed Max .........................55
4.3.2.10.3 Vehicle Speed Min ..........................55
4.3.2.10.4 Vehicle Speed @ Peak ....................55
4.3.2.10.5 Wheel Speed @ Peak .....................55
4.3.2.10.6 Y-Scale Min .....................................55
4.3.2.10.7 Y-Scale Max.....................................55
4.3.2.10.8 X-Scale ............................................55
4.3.2.10.9 Auto Y-Scale ...................................56
4.3.2.10.10 Manual Y-Scale .............................56
4.3.2.11 Locking Interval –Flow Rate Trend Chart ...........56
4.3.2.11.1 Flow Rate Average...........................56
4.3.2.11.2 Flow Rate Max ................................56
4.3.2.11.3 Flow Rate Min .................................56
4.3.2.11.4 Flow Rate Peak ...............................56

Dynatest 1295 Version 1.07 ix Sep 2017
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SECTION DESCRIPTION PAGE
Section 4 4.3.2.11.5 Y-Scale Min ................................56
4.3.2.11.6 Y-Scale Max.....................................56
4.3.2.11.7 X-Scale ...........................................56
4.3.2.11.8 Auto Y-Scale ...................................56
4.3.2.11.9 Manual Y-Scale ...............................56
4.3.2.12 Locking Interval –Misc. Trend Chart ...................57
4.3.12.1 % Slip at Peak.....................................57
4.3.12.2 Time to Peak.......................................57
4.3.12.3 Time to Lockup....................................57
4.3.12.4 Y-Scale Min ........................................57
4.3.12.5 Y-Scale Max........................................57
4.3.12.6 X-Scale ..............................................57
4.3.12.7 Auto Y-Scale ......................................57
4.3.12.8 Manual Y-Scale ..................................57
4.4 Installed hardware field descriptions ..................................58
4.4.2 Force Transducers..................................................59
4.4.2.1 Left Wheel...........................................59
4.4.2.2 Right Wheel.........................................59
4.4.3 Water Equipment and Sensors...............................59
4.4.3.1 Flow Meters.........................................................59
4.4.3.2 Water Pumps.......................................................59
4.4.3.3 Water Tanks ........................................................59
4.4.4.1 DMI Distance Measuring Instrument....................59
4.2.4.4.1 Left Wheel........................................59
4.2.4.4.2 Right Wheel......................................59
4.2.4.4.3 Vehicle.............................................59
4.4.5 Test Start/Stop Devices
4.4.5.1 Pendant...............................................60
4.4.5.2 Photocell.............................................60
4.4.6 Temperature Sensors
4.4.6.1 Air Temperature Sensor......................60
4.4.6.2 Surface Temperature Sensor...............60
4.4.6.3 Left Tire Temperature Sensor..............60
4.4.6.4 Right Tire Temperature Sensor ...........60
4.4.6.5 TankTemperature Sensor....................60
4.4.7 Additional Equipment
4.4.7.1 Printer .................................................60
4.4.7.2 GPS ....................................................61
4.4.7.3 Right of Way Camera ..........................61
4.4.7.4 Vehicle Dash Display ..........................61
4.4.7.5 Inclinometer.........................................61
4.4.7.6 Accelerometer.....................................61
4.4.7.7 Texture Sensor....................................61

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Section 4 4.5 Storage and Printing Field Descriptions............................................62
4.5.1 Data Storage...........................................................62
4.5.2 File Name ..............................................................62
4.5.3 File Directory...........................................................63
4.5.4 Test Set Number.....................................................63
4.5.5 Default File Setting……………………………………63
4.5.6 Output Files ............................................................63
4.6 Miscellaneous .................................................................................63
4.6.1 Test Printing............................................................63
4.6.2 Print Disk Files........................................................64
4.7 F Key Events......................................................................................65
4.8 SN Correction ....................................................................................66
4.9 Diagnostics ........................................................................................67
4.9.1 Encoders and Timers..........................................................67
4.9.1.1 dt meters and measurement theory....................67
4.9.1.2 Speed Meters ....................................................68
4.9.1.3 Encoder Count Meters.......................................68
4.10.1 Analog I/O........................................................................70
4.10.2 Analog Hardware Overview.................................70
4.10.3 Trace Select........................................................71
4.11.1 Digital I/O..........................................................................72
4.11.2 Digital Inputs:Port1,Port2,Port3...........................72
4.11.3 Digital Outputs:Port1,Port2 .................................73
4.12 Testing...........................................................................................75
4.12.1 Test Screen Layout...........................................................75
4.12.2.1 SN Average .....................................................76
4.12.2.2 SN Max............................................................76
4.12.2.3 SN Min.............................................................76
4.12.2.4 SN Standard Deviation.....................................76
4.12.2.5 Traction Average..............................................76
4.12.2.6 Traction Max....................................................76
4.12.2.7 Traction Min.....................................................76
4.12.2.8 Traction Standard Deviation.............................77
4.12.2.9 Load Average...................................................77
4.12.2.10 Load Max.........................................................77
4.12.2.11 Load Min..........................................................77
4.12.2.12 Load Standard Deviation..................................77
4.12.2.13 Speed Average................................................77
4.12.2.14 Flow Average...................................................77
4.12.2.15 Peak SN (PSN)................................................77
4.12.2.16 Time To Peak (TTP).........................................77

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Section 4 4.12.2.17 % Slip ..............................................................77
4.12.2.18 Time To Lockup (TTL)......................................77
4.13 Setups……………………………………………………………………..78
Section 5 Troubleshooting
5.1 Troubleshooting................................................................................79
5.2 Troubleshooting the Software...........................................................79
5.2.1 Rebooting the 1295 Operating Software ............................81
5.2.2 Troubleshooting the 1295 Electronics................................81
Section 6 Maintenance
6.1 Preventative Maintenance................................................................82
6.2 Service Schedule (Tow Vehicle).......................................................82
6.3 Service Schedule (Trailer)................................................................83
6.3.1 Replacing the Trailer Wheel Bearings................................86
6.3.2 Measure Wheel Bearing Endplay.......................................86
6.3.3 Brake Bleeding Procedure (Trailer)....................................87
6.3.4 Verifying/Adjusting Trailer Brake Pressures.......................87
6.3.4.1 Safety Brakes......................................................88
6.3.4.2 Left Or Right Wheel Lockup Brakes.....................88
6.3.4.2.1 Safety Brakes ....................................88
6.3.4.2.2 Test Brake(s).....................................89
6.3.5 Aligning the Water Pump Gearbox with the Drive Shaft .....90
6.3.6 Adjusting the Water Pump Belts (Tow Vehicle).................90
6.3.7 Adjusting the Electric Clutch (Water Pump).......................91

SECTION 1 INTRODUCTION
Dynatest 1295 Version 1.07 1 Sep 2017
1.1 INTRODUCTION
This manual contains the descriptive information, operation, setup, and service instructions forthe 1295
Computer Controlled Pavement Friction Tester manufactured by Dynatest. (Figure 1-1)
The purpose of this manual is to provide the instructions necessary to insure the proper operation and
maintenance of the 1295. Adherence to the instructions will insure satisfactory operation.
1.2 1295 SYSTEM DESCRIPTION
The 1295 Pavement Friction Tester has been developed to perform dry or self-wetted locked wheel
(skid) and peak incipient (slip) friction testing for paved surfaces (see Figure 1-1). The 1295 is designed
to operate at speeds between 20 to 70 MPH (30 to 110 km/hr) while computing the dynamic skid
number FN(t).
The computerized 1295 consists of a fully instrumented tow vehicle and two wheel trailer which uses
one or two M1270 two-axis force transducer(s) mounted on the axle assembly. All electronic
instrumentation is solid state, including a Portable laptop computer and a printer. Windows software
provided with the system allows the operator perform friction testing, enter test information, configure
test settings, calibrate the system and perform system diagnostics .
The on-board computer calculates the dynamic skid number FN(t) from the two-axis force transducer
in real time, and displays the friction and speed traces on the laptop test screen. Test headers, skid
numbers, as well as curves and peak incipient friction, if desired, can be printed or stored on a laptop
hard drive/ SSD. Additional software capabilities include automatic system calibration, full system
diagnostics, and adjustable test cycle timing (within ASTM E274 specifications).
1.3 PRINCIPLES OF OPERATION
Friction testing on pavement is accomplished by using one of two recognized methods. These methods
are the Continuous Peak Friction Test and the Locked Wheel Friction Test. The 1295 Pavement
Friction Tester utilizes the Locked Wheel Friction Test method.
First, the operator selects whether the test is to be dry or wet. Next, the two wheel trailer is brought up
to test speed prior to reaching the test site. The brake on the right or left test wheel is applied until it is
locked. The wheel must achieve lock-up within the pre-programmed limit, while the test vehicle is
held at a constant speed (+/- 1 MPH). Tire braking traction force, vehicle speed, and all other desired
parameters arerecorded when the brake is first applied during the test cycle. Those parameters continue
to be recorded until the test tire is unlocked. Peak and locked wheel sliding forces are calculated by
the computer for each specific test run. The test results are displayed both graphically and numerically
on the laptop, and are stored on hard disk drive.

SECTION 1 INTRODUCTION
Dynatest 1295 Version 1.07 2 Sep 2017
Figure 1-1. Model 1295 Pavement Friction Tester

SECTION 1 INTRODUCTION
Dynatest 1295 Version 1.07 3 Sep 2017
1.4 DAILY START-UP PROCEDURES
1. Some mechanical checks are required to maintain the accuracy of the test vehicle and trailer. It is
recommended that the tow vehicle tire pressure be checked daily to avoid excessive wear on the
tires. The tire manufacturer’s tire pressure recommendations are listed on the tire. The tires
should be inflated to the maximum pressure listed due to extreme weight conditions.
2. Check the trailer tires daily. Prior to each series of tests, warm up the tires by traveling for at least
5 miles (10 km) at normal traffic speeds. Replace the tire if it has been worn beyond the wear
line(s). Set the E501 and E524 test tire inflation pressure at 24 0.5 psi (165 3 kPa) at ambient
temperature just before the 5 mile (10 km) warm-up. (See ASTM E 274).
3. A daily check of the air shocks should be done to verify the proper amount of air pressure is
maintained in them. 50 psi (345 kPa) of air is needed to maintain level and to provide a stable
ride.
4. Proper maintenance of the tow vehicle (as described in the owner's manual) DOES NOT eliminate
the need for daily fluid level checks, belt inspections, etc.
5. A daily visual inspection of the trailer and under the cover should consist of the areas where fluid
leaks may occur. This includes such areas as the brake caliper area on both spindles, the hose
connections, and also in the area of the master cylinder. Detection of leaks may occur early with
the observation of areas with excessive moisture, and/or areas where dirt begins to collect.
6. The water tank, can be filled to its capacity. Verify first that the drain valve is closed. An internal
overflow tube will allow the tank to fill to capacity without flowing over the tank fill tube.
7. If the pneumatic lines are disconnected from the trailer, the tow vehicle pneumatic storage tanks
will maintain their pressure. If the pneumatic lines are NOT disconnected from the trailer, the
system will deplete itself of air pressure. This is due to the design of the valves on the trailer to
continuously exhaust. If the system becomes depleted, the tow vehicle compressor may be used
to recharge the pneumatic system, or the system may be recharged by an external compressor
source.
8. Inspect the trailer jacks to see that they are fully retracted. Inspect the trailer attaching points to
see that the trailer is properly coupled to the tow vehicle, and that the safety chain, water, air, and
electrical connectors are properly connected.
9. It is necessary to calibrate of the DYNATEST 1295 system each time power has been turned off.,
Perform calibration on a level surface, with the tow vehicle in park, and your foot off the brake.
All power must be on (AC and DC). Allow the system to warm-up 15 minutes prior to
calibration. To perform system calibration, refer to Initial Setup.
10. When traveling to and from test sites it is recommended that the DC power and compressor power
be ON to allow the test trailer's service brakes to assist in stopping.

SECTION 1 INTRODUCTION
Dynatest 1295 Version 1.07 4 Sep 2017
1.5 1295 ELECTRICAL SYSTEM COMPONENTS
All electric power for the 1295 is provided by a single 135 amp. alternator driven off the tow vehicle's
engine. The following information is designed to familiarize the operator with the 1295's electrical
system components located inside the tow vehicle's cab.
1.5.1 CONTROL CONSOLE
This console is located between the driver and the passenger seats inside the tow vehicle's cab (see
Figure 1-3). Located on the top of the console are a series of electronic rocker switches and status
lights. The console layout is shown below in figure 1-2.
Figure 1-2. Console Layout

SECTION 1 INTRODUCTION
Dynatest 1295 Version 1.07 5 Sep 2017
1.5.1 CONTROL CONSOLE
AC Power On/Off Switch
Turns power ON and OFF for the 1295's power inverter supplies 120 Volt AC power for the portable
PC and printer.
DC Power On/Off Switch
Turns 12 Volt DC battery power ON and OFF for the 1295's solid state logic, meters, and switching
functions within the main console. This 12 Volt DC battery is located in the rear bed of the tow
vehicle.
Compressor On/Off Switch
Turns 12 Volt DC power ON and OFF to the pressure switch which energizes the air compressor in
the rear bed of the tow vehicle. The compressor is responsible for operating the 1295's air system,
which raises and lowers the Laminar flow water nozzle(s), and controls the air over hydraulic brakes
on the two wheel trailer.
Flasher On/Off Switch
Turns the the alternating flashers on top of the two wheel trailer.
Emergency Stop Button
For immediately terminating the Automatic Test cycle in case of an emergency. Press the button one
(1) time to end the Automatic Test cycle, and release the test brakes. Pressing the emergency button
will abort the pavement friction test in progress.
Operator Pendant Jack
For plugging in the operator hand pendant. The hand pendant is responsible for STARTING the test
cycle. The operator programs the computer to automatically stop the test cycle. This hand pendant is
also used to start and stop the distance calibration of the digital encoders on the two wheel trailer, and
to START and STOP the distance testing.
Compressor Status Light
Indicates when the air compressor in the rear bed of the tow vehicle is pumping air into the air system
on the two wheel trailer. The compressor is automatically controlled by a pressure switch to maintain
approximately 80 PSI (552 kPa). The compressor will not operate during a test run.

SECTION 1 INTRODUCTION
Dynatest 1295 Version 1.07 6 Sep 2017
Processor Ready Status Light
Indicates that the embedded data acquisition computer is running and is ready for Ethernet
communication to the laptop. The laptop should NOT be turned on until the Status light blinks. Once
blinking the light indicates that the communications for the software are ready for use.
If the compressor light comes on during a test, that indicates there is
inadequate pressure to conduct the test, and a test fault may occur.
Figure 1-3. Laptop PC and Control Console
IMPORTANT

SECTION 1 INTRODUCTION
Dynatest 1295 Version 1.07 7 Sep 2017
1.5.2. LAPTOP COMPUTER
The current model 15 inch laptop computer is equipped at minimum with:
Intel Core I7processor @ 2.70 GHz or better
Minimum 8 GB Random Access Memory (RAM).
Ethernet communication ports.
Minimum of a 500 Gb hard disk drive or SSD
The computer operating system is Windows 7 or 10 that includes option to down grade to
Windows 7.
The 1295 Windows software is used for friction testing and data analysis
1.5.3 EMBEDDED DATA ACQUISITION SYSTEM
The data acquisition system is equipped with::
16 channel, 16 bit Analog to Digital Converter
4 channel, 12 bit Digital to Analog Converter.
Optically Isolated Digital I/O.
Ethernet Communication Port.
Serial Communication Ports
1.5.4. OPERATOR PENDANT PUSH BUTTON CONTROL
This control allows the operator to start the automatic test cycle without taking their eyes off the road.
The control can easily be held in one hand during the entire testing procedure.
1.5.5. PRINTER
The printer is supplied for printing hardcopy test results and report printouts.
1.5.6. VEHICLE SPEED DISPLAY
This dashboard mounted meter allows the operator to view the accurate vehicle test speed. The meter
is connected to the system's computer. The right or left test wheel, whichever is not locked during
friction testing, supplies the digital speed and distance pulses to the computer.

SECTION 1 INTRODUCTION
Dynatest 1295 Version 1.07 8 Sep 2017
1.6 TOW VEHICLE REAR BED COMPONENTS
The following information is designed to help the operator identify the electrical and mechanical
components located in the rear bed of the tow vehicle (see Figure 1-4).
Figure 1-4. Tow Vehicle Rear Bed Components

SECTION 1 INTRODUCTION
Dynatest 1295 Version 1.07 9 Sep 2017
1.6.1 250/300 GALLON BAFFLED WATER TANK
This corrosion resistant water tank has interior baffling to minimize the effects of water motion, and a
vent to ensure continuous water flow. At the bottom of the tank is a serviceable water filter to ensure
the self-watering system does not plug. The tank is filled through the screw-on cap located on top of
the tank. Optional larger tank systems available.
1.6.2 12 VOLT DC BATTERY
Operates the 1295's 12 Volt DC electronics. This battery is isolated from the tow vehicle's 12 Volt DC
battery during shut-down.
1.6.3 POWER INVERTER
Supplies 120 Volt AC power to the monitor, computer, printer, and electronic power supplies.
1.6.4 INVERTER BRACKET
This bracket supports the power inverter. Mounted on the outside of the bracket are several relays; one
relay starts the power inverter, and another to starts the air compressor.
1.6.5 12 VOLT DC AIR COMPRESSOR
This compressor is responsible for operating the air system on the two wheel trailer. This air system
raises and lowers the Laminar flow water nozzles and supplies air to the air over hydraulic brakes on
the two wheel trailer.
1.6.6 AIR PREPARATION UNIT
This unit is mounted on the water tank and includes the air filter, dryer, pressure switch, and pressure
gauge for the air system. The drying agent used in the dryer is desiccant. Its condition can be
determined by the color code on the side of its container. New desiccant is blue and turns pink when it
needs to be replaced.
1.6.7 EXTERNAL RETRACTABLE AC POWER CORD
This power cord supplies external 120 Volt AC power to the power inverter for operating the computer
and printer on AC power and for charging the rear battery.
1.6.8 FOUR-WAY AC OUTLET BOX
This AC outlet box allows the operator to plug in the power inverter, used for external AC power-up
of the computer and printer.