Mack CHM 2010, Руководство оператора

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114 OPERATION
Engine Speed Control
Engine Speed Control Operation
The vehicle management and control (V-MAC) IV system also allows the operator to set
and maintain increased engine speeds. The system provides two different speed control
functions: Electronic Hand Throttle control and PTO control. electronic hand throttle (EHT)
controls engine speed when PTO is not engaged.
Both systems allow two modes of control:
1 Single Speed Control (SSC) increases the engine RPM to a speed preprogrammed into the
system memory. This mode is intended for operation of the PTO at maximum efficiency.
2 Variable Speed Control (VSC) allows the driver to set any engine RPM within the
preprogrammed low and high limits set in the system memory. This mode is primarily
intended for general PTO applications and engine warm-up.
Note: Brake conditions are configurable,
but the standard setting is park brake on and
service brake off to engage.
Single Speed Control (SSC)
To use single speed control functions, the following conditions must be met:
1 For power takeoff (PTO) operation, the PTO must be engaged. For electronic hand
throttle (EHT) operation, the service brake must be OFF.
2 The clutch must be engaged (not pressed).
To activate SSC, move the Speed Control switch to the ON position, then press and release
the SET switch. The engine speed (RPM) will jump to the preprogrammed speed. SSC can
also be programmed for Auto Set mode. When enabled, simply move the Speed Control
switch to the ON position and engage the PTO or activate a customer-defined switch (usually
setting the park brake). Engine speed will go to the preprogrammed speed.