BENDIX BW1837 manual Description, Operation

®

SD-15-4111

Bendix® ET- S™ & ET-S2™Suspended Electronic Treadle

TREADLE

POTENTIOMETER

MOUNTING

PLATE

ACTUATOR BODY

MOUNTING

TREADLE PIVOT PIN

PLATE

ACTUATOR BASE

CONNECTOR

TREADLE

		TREADLE
POTENTIOMETER	MOUNTING
ET-S™TREADLE	PLATE	ET-S2™TREADLE

FIGURE 1 - ET-S™AND ET-S2™ELECTRONIC TREADLES

DESCRIPTION

The ET-S™and ET-S2™treadles are engine compartment bulkhead mounted electronic treadles. On electronically controlled diesel engines, the electronic treadle fulfills the same function as a conventional mechanical throttle. However, rather than transmitting a mechanical force to the engine governor, the electronic treadle controls engine speed by supplying a variable electrical voltage to the engine’s electronic controller.

The main components of the ET-S™and ET-S2™treadles are: a mounting plate, suspended treadle, potentiometer (variable resistor), actuator body and base. The selected potentiometer, chosen for a specific engine application, provides the electrical link to the engine control system.

OPERATION

The electronic treadles provide smooth, graduated throttle control through the function of its potentiometer (variable resistor). The drive shaft of the cam follower assembly transfers any movement of the treadle to the potentiometer.

	DETROIT	CATERPILLAR	CUMMINS
	DIESEL
CLOSED
THROTTLE	7 - 18%	10 - 20%	5 - 17%
IDLE (OPEN)
OPEN
THROTTLE	74 - 90%	75 - 90%	70 - 81%
(FULL)

FIGURE 2 - OUTPUT VOLTAGE, AS A PERCENTAGE OF

SUPPLY VOLTAGE

8V			MAX
CATERPILLAR			RPM
5V
ET-S™			ENGINE
TREADLE
OUTPUT	CUMMINS	DETROIT
VOLTAGE
		DIESEL
0V			IDLE
CLOSED THROTTLE		OPEN THROTTLE
(OPEN)		(FULL)

FIGURE 3 - OUTPUT VOLTAGE

1