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V Range 501
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651
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801 Maintenance Manual
MA5:2
Chapter - Pneumatic System
General Description
The air supply for the pneumatic system is taken from the vehicle braking system via a safety regulating
valve that ensures the braking system receives priority in the event of a failure to the sweeper air system. A
filter regulator unit with integral shut off/drain facility and low air pressure warning buzzers are located within
the systems locker, as are the electrical solenoid control valves for operation of channel brush/nozzle and
wide sweep brush, and intake duct flap. Wide sweep brush balance adjustment is provided by electronic
proportional pressure regulators.
Before servicing any components on this system, the air supply should be shut off by means of the
shut off valve mounted on top of the filter regulator unit. This not only severs the pneumatic supply,
it also exhausts the air from the system causing the nozzle and wide sweep brush to lower. Wait
approximately 15 seconds to allow air to completely exhaust before carrying out any work. The shut
off valve does not drain air from the vehicle braking system.
Safety Precautions
Circuit Pressures
The system pressure is pre-set at 8.0 bar (115 PSI).
The pressure in the Powathrust system is preset at 3.5 bar.
The pressure in the Powascrub system (option) is preset at 2 bar.
1
First ensure truck air system is up to pressure and sweepgear is lifted.
2
If pressure is incorrect, adjustment is carried out by turning the regulator control on the filter regulator unit.
Note
:
Provided in the systems locker is an air charge point via an airline push in connector supplied with
the sweeper.
Pneumatic Pipe Colours
A system of colour coding has been introduced to assist pipe identification and fault finding.
The following colours have been adopted.
R
= Red - Permanent/supply
U
= Blue - Switched supply via valve or tap
B
= Black - Permanent vent/exhaust line
Page Issue A
PNEUMATIC SYSTEM - INTRODUCTION
