TPC TIREBOSS - Safety Features

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SERVICE MANUAL
f:tec\manuals\Service\SERVICEv5.indd - V6-0615
TIREBOSS
TM
Tire Pressure Control
SAFETY FEATURES
The TIREBOSS
TM
Tire Pressure Control system (TPCS) incorporates a number of extremely important safety
features to ensure the integrity of the vehicle, tires and the safety of everyone on the highways. These include
features dealing with the following aspects of operation.
1. VEHICLE OVERSPEED CONDITION
If the vehicle’s speed exceeds the set point for the current selected tire pressure, the OVERSPEED CONDITION alert
screen will be displayed and an audible alarm will sound alerting the operator of a vehicle OVERSPEED CONDITION.
If the vehicle OVERSPEED CONDITION persists for a specifi ed period, typically 1 minute (This period is adjustable),
the system will automatically increase the selected pressure setting upward to the next higher tire pressure for the
selected load.
2. LOW AIR BRAKE SUPPLY PRESSURE
A pressure protection valve and an electronic safety switch make sure that air is available for tire infl ations only when
vehicle system air brake pressure is above a safe level (95 psi). If the air brake pressure falls below a safe level, the
LOW AIR SUPPLY alert will be displayed and the air supply is shut off to the TPCS. The supply of compressed air to
the vehicle air brake system always has priority over the TPCS.
3. LOSS OF TIRE PRESSURE
When an unexplained drop in tire pressure takes place in any of the zones, an audible alarm will sound. The tire pres-
sure status display on the operator control unit will fl ash the zone display in which the loss of tire pressure has occurred
and it will alternate with the TIRE PRESSURE LOSS alert. The source of the pressure drop must be located prior to
continuing operation so that appropriate action may be taken, such as isolating the problem tire from the rest of those
in the zone, through the use of manual shutoff valves.
4. AIR FLOW RESTRICTION
The TIREBOSS
TM
system is designed to work normally with all wheel valves open maintaining constant monitoring &
control of tire pressures. If the valves are left in a closed position, the system only senses line pressure and begins
infl ating & defl ating past the set point pressure. This repetitive action will cause the AIR FLOW RESTRICTION ALERT
to be activated. This alert will continue until the valves are re-opened allowing normal operation to resume.
5. TIRE OVER-PRESSURE
The TIREBOSS
TM
system automatically assigns upper and lower limits to the programmable set points. The system
will trim the tire pressures for a preset time, after a new selection is made, to hone in on the new setting. Following the
initial “trimming” time, the tire pressures are allowed to increase above the trim tolerance to allow for normal heat build
up. If the tire pressure exceeds a maximum limit, the TIRE OVER-PRESSURE ALERT will be displayed indicating an
overheat condition in the tire which may be caused from improper pressure settings or a failure of other vehicle compo-
nents, such as the brakes overheating.
6. LOAD SENSING FEATURE (Applicable to air suspension vehicles only)
Vehicles equipped with air suspension on the drive axles can be fi tted with a load sensing option. A load sensing
pressure switch indicates to the control system when the vehicle is loaded and will not allow any of the unloaded set-
tings to be selected. This feature limits the selections to the driver and ensures only the appropriate tire pressures
are being used for current vehicle load.
In addition to the system safety features outlined above, it should be noted that the TIREBOSS
TM
systems
use only quality components, such as DOT approved drive axle air hosing. The TPCS computer continu-
ously monitors tire pressure and controls the infl ating, defl ating, or maintaining of a preselected target tire
pressure. The systems carry operational decaling, which is further explained in an operator’s manual carried
in each vehicle.