Features and Parameters

By turning the energy producing ISL into an energy absorbing air compressor, the engine becomes a highly effective brake on the drivetrain which slows the vehicle. The integrated Engine Compression Brake utilizes the energy from the engine to become a highly effective brake on the drivetrain when necessary which in turn slows the vehicle.

Once installed, the Engine Compression Brake only becomes available to the driver when the cab mounted Engine Brake On/Off switch is set to ON. A second cab mounted switch is provided to control the braking power level when the Engine Compression Brake is activated.

With the Engine Brake switch set to ON, automatic activation of the Engine Compression Brake will occur provided the following conditions are met:

  • The cab mounted Engine Brake On/Off switch must be set to ON.

  • Clutch Pedal must be released

  • Service Brake Pedal must be released

  • Accelerator Pedal must be fully released

  • Cruise control must not be performing an AutoResume

  • PTO/Remote PTO feature must not be active

  • Top 2 Transmission feature must not be active

  • Vehicle speed must be greater than Engine Brake Minimum Vehicle Speed.

Increased flexibility is provided through various options and programmable parameters that allow the user to tailor Engine Compression Brake application and operation to best suit the driving conditions prevailing. These options can be accessed using Cummins PowerSpec configuration tool, and allow the user to modify the method of Engine Compression Brake actuation, rate of brake application and the vehicle speed range in which engine braking is allowed.

Engine Brake Minimum Vehicle
The Engine Brake Minimum Vehicle Speed parameter allows activation of the Engine Compression Brake only when the vehicle is traveling faster than a customer programmable minimum speed. This prevents engine brake operation in urban areas where noise could be a problem, yet still allows full highway functionality.

Select a minimum vehicle speed, in terms of miles per hour at and below which the Engine Compression Brake will be prevented from operating. The minimum vehicle speed range for this parameter is from 0 MPH to 35 MPH.

If a minimum vehicle speed for engine brake engagement is NOT desired, the Engine Brake Minimum Vehicle Speed parameter should be set to ZERO.

Engine Brake Cruise Control Activation
The Engine Brake Cruise Control Activation feature permits the Cruise Control feature to automatically engage the Engine Compression Brake should the selected vehicle speed be exceeded while the Cruise Control feature is controlling the engine. This reduces driver workload and thereby encourages use of the Cruise Control feature.

Cruise Control Speed Delta for Minimum Engine Brake
With the engine controlled by the Cruise Control feature, the Cruise Control Speed Delta for Minimum Engine Brake parameter specifies the amount that the vehicle can increase above the selected Cruise Control vehicle speed before the minimum level of available Engine Compression Brake is automatically activated.

The minimum level of available Compression Brake is determined by the position of the driver controlled, cab mounted Engine Brake Level Switch and the value of the Engine Brake Maximum Level Step parameter up to a maximum value of 33% of available Engine Compression Braking.

The Cruise Control Speed Delta for Minimum Engine Brake parameter should be set at least 1 MPH greater than the Cruise Control Lower droop parameter so as not to interfere with normal Cruise Control speed fluctuations. This is a Cruise Control parameter and is programmed during the configuration of the Cruise Control feature.

Cruise Control Speed Delta for Maximum Engine Brake
With the engine controlled by the Cruise Control feature, the Cruise Control Speed Delta for Maximum Engine Brake parameter specifies the amount that the vehicle speed needs to increase above the selected vehicle speed before the maximum level of available Engine Compression Brake is automatically activated.

The maximum level will be 100% of the available Compression Brake as determined by the position of the driver controlled, cab mounted Engine Brake Level Switch.

The Cruise Control Speed Delta for Maximum Engine Brake parameter should be set to the absolute greatest vehicle speed increase above the programmed Global Maximum Vehicle Speed. The Global Maximum Vehicle speed is defined as the Cruise Control Maximum Vehicle Speed parameter together with any programmed Driver Reward Best Speed Reward parameter.

The Cruise Control Speed Delta for Maximum Engine Brake parameter should be set at least 1 MPH greater than the Cruise Control Speed Delta for Minimum Engine Brake parameter. This is a Cruise Control parameter and is programmed during the configuration of the Cruise Control feature.

Engine Brake Service Brake Activation
The Engine Brake Service Brake feature requires that the driver press or tap the service brake pedal in order to engage the Engine Compression Brake. With the Engine Brake On/Off switch ON, and the Engine Brake Service Brake Activation feature selected, the Engine Compression Brake will not activate unless the service brake pedal is pressed and all other relevant engagement conditions (as described above) are met.

Note that releasing the service brake pedal will not de-activate the engine brake, as this is accomplished by either switching the brake ON/OFF switch to OFF or by altering the position of the accelerator.

Feature / Parameter

Range

Default

Engine Brake Minimum Vehicle Speed - Parameter

0 - 35 mph

0 mph

Engine Brake Cruise Control Activation - Feature Option

Enable/Disable

Disable

Cruise Control Speed Delta for Minimum Engine Brake - Parameter

1.5 - 4.0 mph

2 mph

Cruise Control Speed Delta for Maximum Engine Brake - Parameter

1.5 - 25 mph

4 mph

Engine Brake Service Brake Activation - Feature Option

Enable/Disable

Disable