Installation Manual

Electrical & Electronic Application And Installation Manual
Production Release Version 1.0
Page 129
10.2.7 Engine Emergency Stops
It is the customer responsibility to complete a risk assessment on their product
when considering the use and function of an emergency stop device. If
residual risks remain on the product that the customer wants to mitigate by
use of an emergency stop function, the following methods of emergency
stopping the engine may be considered. The most appropriate method of
emergency stop will depend on the application and appropriate regulations.
Using a combination of the methods below may provide a more robust
emergency stop solution. Using an emergency stop in situations other
than an emergency could result in engine damage . In the event of fuel
shut off solenoid failure, cutting electrical power on mechanical engines may
not stop the engine. In the event of an injector failure, cutting electrical power
on electronic common rail engines may not stop the engine. For detailed
information on how to implement the following methods of E-Stop consult your
applications lead.
• Cut electrical power to engine - un-switched positive
Power should be isolated between the battery positive terminal and the
battery positive pins on the engine ECM.
• Cut electrical power to engine - un-switched positive and negative
Cutting positive power - Power should be isolated between the battery
positive terminal and the battery positive pins on the engine ECM.
Cutting negative return - A double pole/double throw switch should be
placed in a position on machine that will ensure main negative power and
main positive power are disconnected upon switch activation.
• Cut air supply to engine – Slicer valve placed after the
turbocharger compressor.
10.2.8 Common problems with the application of stop devices
It is possible, although extremely rare, that diesel engines continue to run
even if all electrical power is removed. This can happen when high quantities
of oil vapour or other inflammable gases are present in the air into the engine.
The only way to prevent this is to provide an air inlet shut-off valve (slicer
valve). It is not common practice to fit such devices to all engines, but they
should be considered where there is a risk of flammable gases (e.g. in
petroleum applications), or where the application demands high engine grade
ability (slopes).
Some hazards are present when the engine is being cranked by the starter
motor, as well as when it is running. For example, components will still rotate,
hydraulic pressure will still be present, and fuel may still be pump to high
pressures.