Detroit Diesel DDEC VI Application And Installation page 343

DDEC VI ELECTRONIC CONTROLS APPLICATION AND INSTALLATION
5.24 TACHOMETER DRIVE
DDEC VI uses the Camshaft Position Sensor (CMP Sensor) signals to compute engine speed.
The engine speed is transmitted over the SAE J1708/J1587 and J1939 Data Links. Engine speed
can be displayed by connecting a tachometer from the CPC connector pin 1/9. See Figure 5-30.
Figure 5-30 Tachometer Drive Installation
5.24.1 OPERATION
Pin 1/9 provides an engine speed signal for driving an external tachometer.
For engine speeds up to 120 rpm, no signal is output. Above 120 rpm the frequency of the signal
is proportional to the engine speed with 16,040 pulses output per engine revolution.
5-131
All information subject to change without notice. (Rev. 01/07)
7SA827 0701 Copyright © 2007 DETROIT DIESEL CORPORATION