Surveymaster Precision Odometer Mk 3. Firmware version F1.001

Manual Issue F1.001a, November 2001.
Brent Communications, England

Survey Master

The Brantz Surveymaster 1998 model is a distance measuring meter designed to fit to 12 volt road vehicles having either negative or positive ground. The surveymaster case of the Mk3 model is not electrically connected to ground so no damage will occur if it is fitted to a positively grounded vehicle. This model should not be used directly from a 24 volt supply. The device will measure in kilometres to three decimal places (i.e. metres) or in yards or feet according to how it is calibrated via the three digit calibration figure. Max speed is about 100km/hr. Surveymasters come in one of three models; the Surveymaster PC has a 9 pin socket on the base which will communicate its' distance readings to a personal computer running suitable software. The Surveymaster VIDEO model has sockets to permit a video camera to be connected to the input socket and a recorder or monitor to be connected to the output socket. The distance readings will be superimposed upon the output video signal which, if recorded,  makes later analysis of a route simpler if undertaken back at the office. Specify PAL or NTSC system when ordering. An option for all models is the standard plug kit which allows the Surveymaster to be removed quickly from the vehicle. The sensor and part of the plug kit remains in the vehicle.

Installation

The motion of the vehicle is detected by an electronic sensor which is supplied with the meter. This standard speedometer cable sensor is fitted into the vehicle's speedometer cable as per the instructions in the separate sheet. If the vehicle does not have a speedometer cable then the meter can derive its' motion information from different types of sensor. Vehicles which have an electronically controlled speedometer can work the Survey Master via a 'Dividing Prescaler' which is an option to the standard universal speedometer cable sensor. This part is available from the English manufacturers. A further optional sensor is an easy fit gearbox sensor which fits most Japanese vehicles as they have standardized almost all of their speedometer fittings to M22 x 1.5 size. If none of the above sensors are appropriate then a M14 x 1.0 wheel type sensor can be fitted to detect the bolts which hold the brake disc to the rotating wheel hub, or can even detect the rotation of a transmission shaft. Some fabrication of steel brackets and targets will be necessary for this last option by the engineer fitting the meter to the vehicle. The Surveymaster can be mounted in the vehicle by means of brackets to the favoured location within the vehicle. We recommend soft Aluminium strips for this purpose fastened to the four corner screw holes of the meter so as to present low injury risk in the event of a vehicle collision or even 'Velcro' strips.

Wiring

Two cables come out of the base of the Surveymaster. The grey cable goes to the sensor only and is connected as described in the white sensor fitting sheet. If this cable or any of the wires in it are connected to anything other than the sensor then permanent damage will result. The universal speedo cable sensor goes Bn to Bn, Gn/y to Gn/y, Bu to Bu. The black cable emerging from the base of the Surveymaster is the power supply cable. The brown wire within this cable goes to a +12 volts supply which should be fused at no more than two amps. The supply should be permanent (i.e. does not go on or off with the ignition switch) and is best derived directly from the vehicle's battery terminals to avoid the meter being affected by other devices on the vehicle being switched on.The green/yellow wire within the black cable goes to the negative -12v. terminal of the battery. The blue wire within the black cable is not used. Important: Connections must be made using screw type terminals only, as crimp and other similar connectors will not give a sufficiently reliable contact to ensure the accurate working of the Surveymaster.

Operation

To make the meter read accurately it must be calibrated to read the desired units. To calibrate to read kilometres to three decimal places (i.e. metres) set the three digits of the calibration switches to 000. Press the projections above or below each calibration digit to move the value of the digits. The meter is switched on by the switch on the meter. When switched on, the black digits should appear in the lower window of the meter, and the letters CAL will appear in the upper window. To calibrate, drive to the start of an accurately measured kilometre. The lower read-out should be zeroed by the large rocker switch second down on the right hand hand side of the Surveymaster. Press the bottom of this switch and then restore it to its' normal central position. Do not leave this switch in the Hold position (which is the top fully pressed position); the hold will be described later. Drive the measured kilometre and stop accurately at the end of the distance. A three figure number will be in the lower read-out window. Enter this three digit number onto the three digit calibration switches (bottom right hand corner of the surveymaster). Turn the vehicle around and zero the read-outs at the kilometre mark, drive the kilometre accurately and check that the Surveymaster measures the kilometre as 1.000 kilometres. It may be necessary to adjust the calibration figure up or down very slightly to optimize the accuracy within advertised tolerance of 99.6%. Tyre pressures on the vehicle should be kept within ten percent of the manufacturer's recommendations as pressures outside this range could affect accuracy. Above the on/off switch is the switch for the night lights which only work when the main on/off switch is in the 'on' position. There is a TEST MODE accessed by holding the AMEND button pressed whilst powering up. This gives the firmware version in the top window and reads the thumbwheel value in the lower window. The thumbwheel values can be rotated and checked for accuracy. Exit the test mode by releasing the AMEND button .

Other Functions

Pressing the top of the Reverse switch will cause both read-outs to count downwards. Pressing the top of each large rocker switch marked Hold will cause the related read-out to hold its' figure at that point so that notes can be made, but the changes to that read-out continue to be made inside the meter so that when the Hold switch is restored to its' normal central position the read-out will catch up with the distances traveled and the readings will be as if the Hold had never been pressed. The Freeze switch however is for the upper six digit read-out and pressing the top of this switch will stop the top read-out from moving and any distance traveled whilst the Freeze is operated will not be added to that six digit read-out. The two round push button switches marked PRESET are to enter a given figure onto either the top six digit read-out or the bottom four digit read-out. If the top read-out is required to be set to say 123.456 kilometres at a certain point then the left button is pressed repeatedly to select each digit to be modified. As a digit is selected it will flash, and this flashing digit can be incremented by repeated presses of the right button. When all digits have been selected by the left button the next press will quit the editing mode and return to the measuring mode. Alternatively the DIG button can be pressed for a few seconds until the next digit stops flashing and this will exit the editing mode. Following the successful PRESETTING of a value onto the readouts, this same value can be quickly entered again by first pressing the AMEND button, and whilst holding it pressed, press the DIG button momentarily. This facility could be useful for measuring repeat distances probably counting in the downwards direction.

Reliability

Accuracy is greatly dependent on the quality of installation of the Surveymaster. Attention should be paid to first class electrical supply and connections and vibration free installation of the meter and its' sensor. Very high temperatures can cause failure of any of the electronic components on a temporary or permanent basis. Guard against exhaust heat reaching the sensor, and powerful direct sunlight on the meter. Fluids or exceptionally high humidity will cause degradation of the electronic parts. Powerful radio transmissions close to the meter from a transmitter or faulty spark ignition systems will degrade accuracy. If it is noted that the meter steps of its' own accord or zeros itself then radio interference is the likely cause.

Computer Interface Software

The Brantz Surveymaster PC model will talk to PROCOMM and many other serial comms packages (as below diagram). Data is derived in ASCII text format 123.456 3.456 i.e. six digit top readout, space, four digit lower readout. Use a standard serial cable, 9pin to 9pin or 9pin to 25pin, but not a null-modem style cable. Data is transmitted from the meter on demand when ANY ASCII character is sent to the meter. The functions are viewed in an extremely self -explanatory way if the meter is connected to a PC computer running PROCOMM.EXE.

No control of the meter is possible via the comms port other than to demand the information above.

Performance Specification for SurveyMaster mk 3 (April 1999) Power Supply: D.C. 11volt to 14 volt at power lead. Fuse 2 Amps.

RF Immunity: To standards 89/336/EEC

Accuracy: Minimum corrected calibrated accuracy after deducting vehicle errors = 99.6% +/- 1.0 metre.

For metric calibration: Pulse source should be minimum 3 and maximum 6 per metre traveled by the vehicle. Max speed 110kmp . Pulse characteristics are low<1.0v, 4.5v < high < 5.1v. high or low minimum duration 2ms measured with meter connected to the sourced pulse.

rs232 parameters: 9600 bauds, no parity, 8 data bits, 1 stop bit.

data demand: one ascii character sent to the meter at the above parameter and repeated every 20ms up to five times, but only if the previous demand has not been satisfied.

data demand rate: no more than two per second excluding repeat demand as above.

data response: ascii characters displayed, or as logged prior to display.

windows 95/98:

a program compatible to execute under microsoft windows 95/98 from a floppy disk drive is supplied with the surveymaster pc. this program will store distances from the brantz meter to a file along with the key identity which called for the distance information. the program may be copied freely and custom evolutions of this software are available to suit special requirements. the data file can be manipulated by word processors and database programs such as microsoft excel

quiescent state is 12volts. data rate 9600 bits/sec. port settings 9600,n,8,1 ‘d’ connector info: pin 2 = receive data from computer, pin 3 = transmit data from meter, pin 5 = common ground

Download resources

internet explorer: click on any of the resources and select "save this program to disk..."

netscape: hold down shift and click any resource

apple mac: click and hold, then select "download"

highway data collection system: specialized system to collect data from a road survey to be analyzed later by means of a database or similar (220k)

required dll: file required for above software package (973k)

software manual: simple text file (3k) (alternate-click to download)

sample data: sample data used to test software package (1k) (alternate-click to download)

[Laser3] [International 1] [International 2] [International 2 'S'Pro] [Architects] [Survey Master] [RetroTrip 2] [RetroTrip 3] [Rally Timer ] [Marshal Clock] [Variable Timebase Clock] [Sensors]