Bendix Commercial Vehicle Systems ET-S SUSPENDED ELECTRON TREADLE6/04 User Manual
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FIGURE 8 - ELECTRICAL TEST SCHEMATIC FOR THE CUMMINS CONNECTOR
(c) For Cummins Potentiometers:
Test 1: Where the set resistance and voltage is
shown on a label. The Cummins potentiometer on
the ET-S
™
and ET-S2
™
treadle has an integral idle
validation switch. It also has a set resistance value
marked on the cover, which needs to be used to properly
install the potentiometer. The drive slot in the
potentiometer should engage with the drive tang at the
end of the drive shaft. Next rotate the potentiometer
until the hole in the metal sleeve matches the mounting
holes on the actuator base. Loosely screw the
potentiometer in place but do not tighten. Connect an
ohmmeter to pins 3 (APS output) and 4 (APS ground)
as shown in Figure 8. Now the installer should read the
set resistance value marked on the label. Rotate the
potentiometer until the ohmmeter reads the same
resistance as shown on the label within ±10 Ohms. Next,
while holding the potentiometer at the set resistance
screw and lock the potentiometer in place (torque to 25
inch pounds ±5). The sleeves lock into the body of the
potentiometer for easy removal and reassembly.
Test 2: Where the potentiometer has no label, but
has engraved set voltage shown. The Cummins
potentiometer on the electronic treadle has an integral
idle validation switch. It also has a set voltage value
marked on the cover, which needs to be used to properly
install the potentiometer. The drive slot in the
potentiometer should engage with the drive tang at the
end of the drive shaft. Next rotate the potentiometer
until the hole in the metal sleeve matches the mounting
holes on the actuator base. Loosely screw the
potentiometer in place but do not tighten. Construct the
test circuit following the circuit diagram shown in Figure
8. To make the test circuit connect the test load resistor
(47,000 Ohms) and a capacitor (.01 MicroFarads) across
pins 3 and 4 of the potentiometer. Then connect a
voltmeter to the lead ends of the test circuit. Next connect
a 5 volt power supply to the potentiometer at pin 4 (APS
ground) and pin 5 (supply voltage). Caution: Sensor
may be damaged if supply exceeds 5 volts. Now the
installer should read the set voltage value marked on
the potentiometer. Rotate the potentiometer until the
voltmeter reads the same voltage as shown on the
potentiometer within ±.02 volts. Next screw and lock
the potentiometer in place (torque to 25 inch pounds
±5). The sleeves lock into the body of the potentiometer
for easy removal and reassembly.
Test 3: Perform the following Operational Test before
installing the electronic treadle:
OPERATIONAL TEST
[Note for Cummins potentiometers only: The optimum
output & switch points should be achieved when the idle
voltage equals the set voltage or set resistance written on
the potentiometer. Use the test circuit shown in Figure 8.]
a. Check that the electronic treadle mounting plate is
securely attached to a smooth, flat surface in such a
way that does not twist the unit.
.01µ F
TEST LOAD
47000 OHM
IDLE
VALIDATION
SWITCH
IVS
PEDAL
POSITION
SENSOR
PIN 3
PIN 4
PIN 5
Vs
SUPPLY
VOLTAGE
V1
(OUTPUT)
APS
GROUND
PIN 2
PIN 6
PIN 1
TEST
LOAD
470
OHM
TEST
LOAD
470
OHM
Vs
SUPPLY
VOLTAGE
DIODES
Closed Throttle (open) Range: 5-17%
Open Throttle (full) Range: 70-81%
V3 (LOGIC HIGH AT IDLE)
V2 (LOGIC LOW AT IDLE)
IVS GROUND
3
V1
(OUTPUT) SIG1
2
(IVS) V 2
1
IVS GROUND
6
(IVS)
V 3
5
VS
(INPUT)
4
APS GROUND
POTENTIOMETER
SET VOLTAGE
AND PC. NO.
SHOWN
HERE
LOCK TAB
LOCK TAB