Propeller Shaft; Brakes; Brake Chamber Effective Area; Air System - PREVOST H3-45 2023 Operator's Manual

9-12 Technical Information

PROPELLER SHAFT

Dana Spicer SPL250 type tubular shafts,
provided with heavy-duty universal joints.

BRAKES

The features of the braking system include a dual
system where the front and rear circuits are
completely independent from each other. The
brakes are air operated disc type brakes. The
emergency/parking brakes are located on the
drive axle. To ensure a constant running
clearance between pads and disc, the brakes are
equipped with a non-wearing, automatic adjuster
mechanism.

BRAKE CHAMBER EFFECTIVE AREA

2
Front axle: . . . . . 24 in
Drive axle: . . . . . 24/24 in
2
Tag axle: . . . . . 16 in

AIR SYSTEM

Compressed air is provided by a twin cylinder,
31.8 cfm Wabco, gear-driven, water-cooled and
engine oil lubricated air compressor.

ANTILOCK BRAKING SYSTEM (ABS)

The antilock braking system has one Electronic
Control Unit (ECU) controlling a 6- sensor/5-
modulator (6s/5m) system. A wheel slip sensor is
mounted at each wheel.
The Electronic Control
maintenance free. Its operating voltage is 24 ± 6
volts DC. The thermal operating range for the
ECM is from -40 to 167°F (-40 to 75°C).
The solenoid control valves are maintenance
free. Their operating voltage is 24 (+4.8, - 2.4)
volts DC. The rated current draw is 1.65 amps.
The thermal operating range of the solenoid
control valves is from -40 to 176°F (-40 to 80°C).
2
(service /emergency)
Module (ECM) is
PA-1652 Operator's Manual H3-45 Coach

TROUBLESHOOTING AND TESTING

For detailed information, troubleshooting and
testing refer to Bendix booklet "Bendix Service
Data EC80 ESP Controller (SD-13-4986)" found
on the Technical Publications USB flash drive
and web site.
AUTOMATIC TRACTION CONTROL
(ATC) – ELECTRONIC STABILITY
CONTROL (ESC)
In addition to the ABS function, vehicle is
equipped with a Traction Control System (TCS)
feature. This feature is provided by the Bendix
ESP EC- 80 controller. Bendix refers to this
feature as Automatic Traction Control (ATC).
Bendix ATC can improve vehicle traction during
acceleration, and
accelerating through curves. ATC utilizes Engine
Torque Limiting (ETL)
communicates with the engine's controller and/or
Differential Braking (DB) where individual wheel
brake applications are used to improve vehicle
traction.
The ESP EC-80 model controller also provides
an ABS-based Electronic Stability Control (ESC)
feature. Bendix refers to it as ESC Electronic
Stability Control.
The Bendix ESC system is an ABS- based
stability system that enhances vehicle stability by
both reducing engine throttle and by applying
vehicle braking based on actual vehicle dynamics
Refer to Maintenance Manual, Section 12: Brake
and Air System for more information on this
system.
CAUTION
Even with ESC- equipped vehicles, the driver
remains responsible for ensuring vehicle stability
during operation.
DANGER
ESC may reduce
automatically.
ESC can make the
automatically. ESC can slow the vehicle with or
without the operator applying the brake, and
even when the throttle is being applied
lateral stability while
where the ECU
the vehicle speed
vehicle decelerate