6D3-10 STARTING AND CHARGING SYSTEM
The generator has four external connections; the "B+" lead to
battery positive, "L" lead to the warning lamp circuit(max. 2
watts), "S" lead to battery positive terminal for battery sensing
and an earth connection.
Explanation of type inscripiton
Example:KC-A--> 14V 50-90A.
K = Code for Stator OD(126mm OD).
C = Compact Generator.
A = Ausland (countries other than Germany)
> = Direction of rotation(clockwise).
14V = Generator Operating Voltage.
50A = Stabilised output at 25 C at 1800 RPM./13.5
Volts.
90A = Stabilised output at 25 C at 1800 RPM./13.5
Volts.
Generator Connetions.
B+ : Battery Main Connection (battery positive)
S : Battery Sense Connection(battery positive)
L : Waring lamp(via warning lamp to Ignition switch)
BATT.SENSE
REGULATOR ASSEMBLYHYBR10ALTERNATOR ASSEMBLY
12V BATT.1GN.SW.
300a* WARN.LAMP
1.2 WATT
L S8+SUPPRESSOR
CAPACITOR
0.5
f
NOTE: * RESISTOR IS RECOMMENDED TO
ENSURE THAT THE GENERATOR
REMAINS FUNCTIONAL IN CASE OF
WARNING LAMP FAILURE
STARTING AND CHARGING SYSTEM 6D3-11
Warning
Do not reverse S and L connections as this will destroy the
warning lamp circuit of the regulator.
Ensure good electrical contact beween generator earth and
battery negative,
Operation
With the Iginiton switch turnded "ON", current is supplied via
the warning lamp to the "L" terminal of the regulator. Base
current is fed to T15 causing it to turn on, current then flows
from B+ through the rotor winding via the regulator brushes
and the collector emitter junction of T15 to earth completing
the circuit. The current in the rotor causes a magnetic field
between adjacent poles to be created, this field is rotated and
cuts the windings of the stator at right angles inducing a
voltage into them.
As the speed is increased this induced voltage increases and
results in curent being rectified in the 3 phase diode bridge and
supplied as DC to the B+ output and hence to the battery.
When the voltage at the B+ terminal of the battery reaches
around 14.2 volts, this voltage is monitored by the "S" lead and
turns the regulator Hybrid base current to T15 OFF removing
rotor current, resulting in a decrease in output voltage to below
the regulating voltage, T15 base current turns ON and the
whole cycle is repeated very rapidly.
D38 protects T15 and the regulator against the back voltage
developed across the rotor winding when T15 turns OFF.
The new generated EP regulators incorporate current limiting
in the warning lamp circuit.
Backup Regulation
The EP regulator will limit the output voltage to a safe level
should either the main B+ cable or the battery sense wire
become decoupled, the output voltage will be slightly above the
normal setting(1-3 volts).
Start up phase
When the Iginition switch is turned on and the engine is not
running, the current to the rotor is reduced by switching it on
and off at a 50% duty cycle, the frequency is approximately 4
KHz and may be audible at times.
This is quite normal, once the engine is started normal
regulation commences.
Warning lamp failure
Should the warning lamp fail, the generator will self excite by
deriving a small current from the phase connecion allowing the
voltage to build up to regulating level.
Note: no filed current will flow when the engine is cranking.
6D3-12 STARTING AND CHARGING SYSTEM
Diagnosis
The EP regulator incorporates diagnostics which will illuminate
the warning lamp as a result of fault conditions in the generator
and external circuitry.
These conditions include:
1.
An open circuit in the regulator battery sensing wire (S
Terninal)
2. An open circuit or excessive voltage drop in the B+ cable.
3. An open circuit in the generator phase connection.
4. Overcharging of the battery.
5. Regulator output stage short circuit.
6. Open circuit rotor.
The regulator compares the voltage at B+ with the voltage at
the "S" terminal connceted to battery positive. If the voltage
differential exceeds a predetermined threshold, the regulator
will operate in backup mode to limit the output voltage to a safe
level. The warning lamp; will remain illuminated as along as
these conditions prevail.
Sources of high resistance which will trigger the warning lamp
are:
a. Poor contact in wiring harness connectors.
b. Poor contact between rectifier and regulator.
c. High resistance in fusible link assembly.
Caution:
When bench testing the generator it is important that the
warning lamp wattage of 2 watts is not exceeded.
Reversal of the "S" and "L" on the regulator will damage
the regulator.
The correct plug for the regulator is a 9 122 067 011 for the
Bosch tye and for the Shinagawa connector the number is
X02FW.
See appendix 1 for daignostic matrix.
Before testing or disassembling the generator please observe
the following points.
1. When testing the diodes with AC type testers the RMS.
Vlotage output must not exceed 12.0 volts, it is
recommended that the stator should be disconnected
during this test.
2. Where zener power diodes are used, the breakdown
voltage should be tested to ensure all diodes have the
same zener voltage.
3. Insulation tests on the rotor and stator should use a voltage
not exceeding 110v for a series test lamp. The rectifie
r
must be disconnected from the stator prior to testing.
4. When carrying out repairs to the charging system always
disconnected the battery negative first, and reconnect i
t
last.
STARTING AND CHARGING SYSTEM 6D3-13
5. During current output tests please make sure that the
ammeter is securely connceted into the charge circuit.
6. Some battery powered timing lights can produce high
transient voltages when connected or disconnected. Onl
y
disconnect or connect timing lights when the engine is
switched off.
7. Make sure the warning lamp circuit is functioning normall
y
before commencing tests.
8. Battery isolation switches must only be operated when the
engine is stopped.
9. To protect the charging system when using 240 vol
t
chargers it is recommeneded that the battery is
disconnected whilst charging.
10. Due to the very low resistance value of the stator winding i
t
may not be possible to obtain accurate readings withou
t
special equipment.
11. 12 volts must never be connected to the "L" terminal of the
regulator as this will damage the lamp driver circuit.
12. No loads apart from the warning lamp can be connected to
the "L" termainal. The "W" terminal is provided for this
purpose.
Disassembly
1. Mark the relative positions of the end housings in relation to
the stator assembly to aid reassembly. Use a permanen
t
marking pen do not use centre punched as this can cause
misalignmnet of the housings.
2. Remove the EP regulator from the slipring end housing b
y
removing the two screws. Tilt the regulator slightly from the
plug connection until the regulator clears the housing, then
lift clear.
3. Remove the four through bolts.
4. Carefully remove the stator assembly along with the slipring
end housing taking care not to put strain on the stator wires.
5. To disconnect the stator from the rectifier assembly, grasp
the stator wires close to the wire loop with a pair of long
nosed pliers, heat the joint with a soldering iron, when the
point becomes plastic apply a slight twisting motion to the
wires, then pull upwards to release the wires. Remove the
stator.
This procedure opens the wire loop to release the stato
r
connections easily.
6. To remove the rectifier remove the three retaining scre
w
and the B+ terminal nut and washers.
Note: the B+ bolt and the positive heatsink retaining screw are
fitted with mica insulating washers.
These must be discarded and replaced with new washers and
heatsink compound.
6D3-16 STARTING AND CHARGING SYSTEM
Readings for Zener diode groups 011 to 042
Zener voltage at
5Ma.Positive
diodeNegative
diodeFordward
current Rating
17.8v-19.2v 011 012 25A
18.8v-20.2v 013 014 25A
19.8v-21.2v 015 016 25A
20.8v-22.2v 017 018 25A
21.8v-23.2v 019 020 25A
22.8v-24.2v 021 022 25A
17.8v-19.2v 031 032 35A
18.8v-20.2v 033 034 35A
19.8v-21.2v 035 036 35A
20.8v-22.2v 037 038 35A
21.8v-23.2v 039 040 35A
22.8v-24.2v 041 042 35A
Note: Diode number is stamped on the rear of the diode.
2. Stator
Inspect the stator insulation resistance to ground with an
insuation tester or a series test lamp up to 110 volts.
The insulation resistance must be greater than 1 megohm.
The winding reisistance is measured between phases using a
low reading ohmmeter designed for this purpose, the values
are given at the rear of this instruction.
3. Rotor
Inspect the rotor for insulation resistance to ground using an
insulation tester or a series test lamp up to 110 volts.
The insulation resistance must be grater than 1 megohm.
Measure the rotor resistance between the sliprings using an
ohmmeter or apply 12 volts across the sliprings and measure
the rotor current flow, then divide 12 by the measured current,
the results is the rotor resistance in ohms. values are given at
the rear of this instruction.
If the sliprings are worn or out of round they must be re-
machined to a minimum diameter or 26.7 mm and should have
a runout not exceeding 0.060mm. If the slipring is below these
limits it must be replaced with a new one.
Warning; extreme care must be exercised when machining
the slipring as it is possible for the turning tool to foul the
STARTING AND CHARGING SYSTEM 6D3-17
fan.
4. Replacing the brushes (inbuilt regulator)
Check the brushes for length, this is measured from the brush
holder to the end of the brush along it's centre line. Also
inspect for any sideways wear. If worn replace both brushes.
The minimum length is 3.8mm. Inspect the brush springs for
signs of corrosion or loss of tension or uneven tension.
Replacing the brushes, using a soldering iron apply heat to the
soldered joints on the rear of the brush holder of the regulator,
using a small lever prise up the retaining tabs to release the
brush lead and spring. Thread the new brush lead up the
brush holder along with the spring, pull the lead through the
tabs until the brush is protruding 12mm from the holder.
Bend down the tabs and solder the brush lead taking care not
to allow the solder to run up the lead which will reduce
flexibility. Use 60/40 resin cored solder.
5. Ball bearing
Please note the bearings used in this KCA generator are a
high
tolerance type, only fully sealed bearings of the same
specification are to be used as replacements. It is
recommended that the bearings be replaced during the
reconditioning process to restore the unit to original
specification.
6. Regulator
The regulator can only be tested when fitted into an altenator.
Warning: do not reverse"S" and "L" connections or put 12
volt supply to "L" terminal, this connection must not be
used as a supply source other than to supply the
requirements of the warning lamp 2(watts).
Such action will destroy the regulator warning lamp
circuit.
For test voltages refer to Generator output testing section.
See also additional information on regulator function earlier in
this instruction.
STARTING AND CHARGING SYSTEM 6D3-19
Inspection
Generator
Before any in field testing can be undertaken it is important
that the battery's conditions is established and the terminals
are clean and tight.
Check the condition of the generator drive belt and ensure that
it is adjusted in accordance with the engine manufacturer's
recommnedations.
Battery conditions:
Note: This assessment may be difficult with maintenance free
assemblies.
Test the specific gravity of the individual cells the readings
should be within 10 points of each other, it is recommended
that the average SG should be 1.260 or higher.
A load test should be carried out to determine the ability of the
battery to supply and accept current. This is a good indicator
as to the general condition of the battery.
A load equal to the normal starting current should be placed
across the battery, the duration of this load test should not
exceed 10 seconds, during this time the terminal voltage
across the battery should not drop below 9.6 volts. Observe
each cell for signs of excessive gas liberation, usuall an
indication of cell failure.
If the battery test is clear proceed with the Generator tests as
follows.
Care should be taken when making the following connections.
It is recommended that the battery negative terminal be
disconnected before the test meters are connected, and
reconnecting the negative terminal when the meters are
inserted into the circuit under test. The warning lamp in the D+
circuit should not exceed 2 watts.
Regulating voltage test on the vehicle.
Connect a voltmeter to the generator, the positive lead to the
B+ terminal and the nagative lead to the generator casing.
Select the voltage range to suit the system, i.e. 20v for 12 volt
sysytems or 40v for 24 volt systems. Connect an ammeter in
series with the main output cable from the B+ terminal on the
generator, the range selected must be capable of reading the
maximum output from the generator.
Note the voltmeter reading before starting the engine. This
reading should increase when the engine is running indicating
generator output, start the engine and increase the engine
speed until the generator is running at 4000 rpm, switch on
vehicle loads of 5-10 A is indcated on the ammeter, the
voltmeter shoud read 14.0-14.2 v for a 12 volt system, for a 24
volt system the readings should be 5-10 A and 27.7-28.5 volts.
STARTING AND CHARGING SYSTEM 6D3-21
Technical Data
(mm)
Brush wear - Minimum Length 3.8
Sliprings - Minimum Diameter 26.7
Sliprings - Trueness <0.06
Pole claws - Trueness <0.05(93.25
0.05)
Torque
N.m(kgf
m)
Pulley retaining nut 54-68(5.5-6.9)
Capacitor retaining screw 2.7-3.8(0.3-0.4)
Capacitor whiz nut 1.5-2.2(0.1-0.2)
B+ terminal nut M8 7.5-8.5(0.8-0.9)
B+ terminal rectifier nut 6.0-7.5(0.6-0.8)
Regulator retaining screw 1.6-2.3(0.1-0.2)
Rectifier retaining screw 1.6-2.3(0.1-0.2)
Bearing retaining plate screw 2.1-3.0(0.2-0.3)
Through bolt 3.8-5.5(0.4-0.6)
Winding resistance(between phases)
(
)
Stator Rotor
70 Amp generator 0.086+10% 2.6
0.13
85 Amp generator 0.058+10% 2.6
0.13
90 Amp generator 0.056+10% 2.6
0.13
Warning lamp fault indication
Fault running Generator not
running Ignition ONGenerator
Iginiton ON
Generator out cable
O/CON ON
Battery "S" cable O/C ON ON
Battery overcharged ON ON
Positive diode short OFF ON
Negative diode short ON ON
Positive diode open ON OFF
Negative diode open ON OFF
Phase voltage sensing ON ON
cable open circuit
Power transistor
shortedON ON
Warnign lamp driver
O/COFF OFF