Starter Lockout - Detroit Diesel DDEC VI Application And Installation

DDEC VI ELECTRONIC CONTROLS APPLICATION AND INSTALLATION
5.23

STARTER LOCKOUT

The Starter Lockout function protects the starter motor from over-speed damage, e.g. re-engaging
the starter motor while the engine is running.
5.23.1 OPERATION
The Starter Lockout output circuit drives a normally closed relay, which interrupts the starting
signal when the output has been activated.
If enabled, the Starter Lockout output will be activated when the engine speed exceeds the
minimum speed for the starting motor for a maximum amount of time. To ensure that the
engine would start even under worst conditions, the over-speed time condition will be added to
the engine speed condition before the starter is locked out. Both values, maximum speed and
minimum over-speed time, are dependent on the coolant temperature. The output is disabled
when the ignition switch has been cycled to off or the engine is not running, i.e. the engine
speed has a value of zero.
The cranking time is limited to a programmed value to keep the starting motor from over crank
damage. The starter lockout relay will be activated when cranking time exceeds this lockout limit.
Since the starter signal is not available, the engine speed will be monitored to detect when the
engine is cranking. When the starter engages, engine speed rises from zero to starter cranking
speed. After this has been detected, engine speed will not be below the programmed speed for
over-crank detection for the programmed maximum starter crank time.
If the driver is still turning the start key and the engine doesn't start while the maximum crank
time expires, the starter lockout relay will be activated to shut off the starting engine. In this
instance, the starter lockout relay will remain activated until the programmed lockout time expires
and the engine has stopped. This allows the starting motor to cool down before the driver is
permitted to start the engine again.
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All information subject to change without notice. (Rev. 01/07)
7SA827 0701 Copyright © 2007 DETROIT DIESEL CORPORATION