C.E. Niehoff & Co. N1388-1 Troubleshooting Guides - Manual

Page 1
TG0047A
Table of Contents
Section A: Wiring Diagram .......................................2
Section B: Basic Troubleshooting .............................3
Section C: Advanced Troubleshooting ......................4
Battery Conditions
Until temperatures of electrical
system components stabilize, these
conditions may be observed during cold start voltage tests.
• Maintenance/Low Maintenance Battery:
— Immediately after engine starts, system volts are
lower than regulator setpoint, and amps are
medium.
— 3-5 minutes into charge cycle, system volts
increase and amps decrease.
— 5-10 minutes into charge cycle, system volts
increase to, or near, regulator setpoint, and amps
decrease to a minimum.
— Low maintenance battery has same characteris-
tics with slightly longer recharge times.
• Maintenance-free Battery:
— Immediately after engine starts, system volts are
lower than regulator setpoint with low charging
amps.
— Once the charge cycle begins, low volts and low
amps are still present.
— After the alternator energizes, volts will increase
several tenths. Amps will increase gradually,
then quickly to medium to high amps.
— Finally, volts increase to setpoint and amps
will
decrease.
The time it takes to reach optimum voltage and am-
perage will vary with engine speed, load, and ambient
temperature.
• High-cycle Maintenance-free Battery:
— These batteries respond better than standard
maintenance-free. Charge acceptance of these
batteries may display characteristics similar to
maintenance batteries.
NOTICE
Hazard Defi nitions
These terms are used to bring attention to presence of hazards of
various risk levels or to important information concerning product
life.
Indicates presence of hazards that
will or can cause minor personal
injury or property damage.
Indicates special instructions on
installation, operation or mainte-
nance that are important but not
related to personal injury hazards.
CAUTION
NOTICE
1300 Series Troubleshooting Guide
for N1388-1 Alternator
Charge Volt and Amp Values
Voltage and amperage levels are functions of the battery
state of charge. If batteries are in a state of discharge,
as after extended cranking time to start the engine,
system volts when measured after the engine is started
will be lower than the regulator setpoint, and system
amps will be high. This condition is normal for the charg-
ing system. Measured values of system volts and amps
will depend on the level of battery discharge; in other
words, the greater the battery discharge level, the lower
the system volts and higher the system amps will be.
Voltage and amperage readings will change: System volt-
age reading will increase to regulator setpoint, and sys-
tem amps will decrease to low level (depending on other
loads) as batteries recover and become fully charged.
• Low Amps: Minimum or lowest charging system amp
value required to maintain battery state of charge;
obtained when testing the charging system with a
fully charged battery and no other loads applied. This
value will vary with battery type.
• Medium Amps: System amp value that can cause
battery temperature to rise above adequate charg-
ing temperature within 4-8 hours of charge time.
To prevent battery damage, charge amps should be
decreased when battery temperature rises. Check bat-
tery manufacturer recommendations on proper rates
of charge amps.
• High Amps: System amp value that can cause battery
temperature to rise above adequate charging tempera-
ture within 2-3 hours. To prevent battery damage,
charge amps should be decreased when the battery
temperature rises. Check battery manufacturer rec-
ommendations on proper rates of charge amps.
• Battery Voltage: Steady-state volt value measured
with battery in open circuit with no battery load. This
value relates to battery state of charge.
• Charge Voltage: Volt value obtained when charging
system is operating. This value will be higher than
battery voltage and must never exceed the regulator
voltage setpoint.
• B+ Voltage: Volt value obtained when measuring
voltage at battery positive terminal or alternator B+
terminal.
• Surface Charge: Higher-than-normal battery voltage
occurring when battery is removed from battery char-
ger. Surface charge must be removed to determine
true battery voltage and state of charge.
• Significant Magnetism: Change in strength or inten-
sity of a magnetic field present in the alternator rotor
shaft when the field coil is energized. The magnetic
field strength when the field coil is energized should
feel stronger than when the field is not energized.
• Voltage Droop or Sag: Normal condition which
occurs when the load demand on an alternator is
greater than rated alternator output at given rotor
shaft RPM.