AFamiliarization

to Speed Governor

Anil ChhikaraAnil ChhikaraMotor Licensing OfficerMotor Licensing OfficerTransport Department Transport Department GNCT, DelhiGNCT, Delhi

SPEED LIMITER

CABLE MECHANISM TYPE

FUEL MANAGEMENT TYPE

SPEED GOVERNOR

Also called as SPEED LIMITER DEVICE(SLD)ELECTRONIC SPEED GOVERNOR

(ESG)SPEED CONTROL DEVICE (SCD)

DEFINITION

Speed limiting device has primary function to control the fuel feed to the engine in order to limit the speed of the vehicle to a specified value without effecting the other performance parameter of the vehicle .

TYPES OF SPEED GOVERNOR

TYPE PRINCIPLE PERFORMANCE

MECHANICAL Welding of iron strip or bolt just below the accelerator pedal to restricts the engine rpm.

Lack of power Pickup of vehicle falls

drastically.

CABLE MECHANISM

Microcontroller receives the input signal from the speed sensor and send the signal out to the actuator

Actuator cuts the fuel & air intermittently and not let run the engine above prescribed speed.

FUEL MANAGEMENT

Management of calibrated fuel through ECU to control the vehicle speed.

Steady specified speed is achieved without any hiccups ensuring smooth ride.

MAIN COMPONENTS

SPEED SENSOR

ELECTRONIC CONTROL UNIT

ACTUATORS

WIRING HARNESS

SPEED SENSOR

REED SWITCH TYPE – redundant/non reliable technology

HALL EFFECT TYPE – latest / reliable technology

HALL EFFCT SENSOR

The Hall element is a small semiconductor plate when a current is pass through it in the presence of magnetic field generate voltage . This voltage is proportional to current and the magnetic field. This generation of voltage is called Hall effect.

Hall Effect Sensor

ELECTRONIC CONTROL UNIT

This is an electronic circuit contains an array of resistance and capacitors with a 32 bit microcontroller, where all the input signal are analyzed and passing through the whole algorithms of software then a suitable out put is generated for final control elements called Actuator.

Actuators

The actuator is a translation of the converted controlled signal in to action .

It is an energy conversion device having an electrical input as signal and force and displacement as an output.

Mechanical

Electrical Solenoid

TEMPER PROOFNESS

Vehicle speed should not cross the set speed if any of the below condition occurred.

If sensor is bypassed If ECU is bypassed If wiring is bypassed If complete system is

bypassed

MECHANISM OF CABLE TYPE SPEED LIMITER

Regulation of speed of vehicles

Motor Vehicle Act , 1988 Sections 183,112,184,66

Central Motor Vehicle Rules, 1989 , Rule 118 Delhi Gazette Notification F. No

PCO/STA/II/2001PF-2/194 Dated 24 February 2003 & subsequent guidelines dated 17-02-2007

SLD Standards AIS 018, IS :10250, IS : 9000

REGULATION /ENFORCEMENT ON ROADS

In no case transport vehicle should run above 40 kmph in Delhi roads.

ESG should not be tempered .Seals of ESG should be intact.ESG should not be removed .Annual Maintenance Contract /History

card should be kept along the vehicle documents.

MAINTENANCE OF ESG

Quarterly calibration and maintenance services are mandatory.

No road side mechanic /unauthorized technicians are allowed to repair the ESG.

In case ESG defective the vehicle is not allowed to ply on hire – reward purpose.

The operator / driver may get repairs/correction from authorized dealer workshops.

ECU

Gear BoxEngine

Actuator Motor

Accelerator Pedal

Location inside driver cabin

Location Inside cabin or under chasses.

Electronic sensor cable

Speed sensor

Accelerator linkages

Sealing locations

ECU

Gear BoxEngine

Actuator Motor

Accelerator Pedal

Location inside driver cabin

Location Inside cabin or under chasses.

Electronic sensor cable

Speed sensor

Accelerator linkages

By pass switch

Electronic By-passing with intact seals

Main seals are located at the sub - assemblies i.e. speed sensor, ECU & Actuator Motor

The other seals are fixed at accelerator linkages depending upon model of ESG & vehicle which can be additional one or two.

The possibility of electronic tempering may not be ruled out even the seals are intact, if the insulation of the sensor pulse wire is sheared off and the earthed with the help of shunt (additional piece of wire) and with the help of a switch located at convenient reach of driver.

The driver can by-pass the speed governor and the vehicle speed can shoot up to his desire.

In case some other tempering is carried out the chances of SLD at working mode will not be possible and will damage the electronic components.

Tempering of the SLD

SEAL LOCATIONS - a

At gear box / speed sensor

SEAL LOCATION -b

At ECU

SEAL LOCATION- c

At throttle / linkages

THANKING YOU