C.E. Niehoff & Co. N1313 Troubleshooting Guides - Manual (Page 2)

Page 2
TG16F
Section A: Description and Operation
CEN N1313 Dual Voltage Alternator
Description and Operation
N1313 300 A (28 /14 V) dual voltage alternator is inter-
nally rectified. All windings and current-conducting
components are non-moving, so there are no brushes or
slip rings to wear out. Energize switch (commonly an oil
pressure switch or ignition switch) activates regulator.
Field coil is then energized when rotation is detected.
Upper voltage (28 V) is rectified with standard diodes.
Lower voltage (14 V) circuit output current is controlled
by SCRs. Alternator output current is self-limiting and
will not exceed rated capacity of alternator.
N3039 and N3222 regulators used with these units also
• are flat temperature compensated. Setpoints are
28.0 ± 0.2 V and 14.0 ± 0.2 V.
• provide overvoltage cutout (OVCO). Regulator will
trip above 32 V for 28 V system (16 V for 14 V
system) longer than 2 seconds. OVCO feature detects
high voltage and reacts by signaling relay in F–
alternator circuit to open, turning off alternator.
Restarting engine resets OVCO circuit. If vehicle is
run in OVCO mode, OVCO will automatically reset
when system voltage drops to 22 V. Regulator
regains control of alternator below output voltage.
• maintain alternator output voltage at regulated
settings as vehicle electrical loads are switched
on and off.
B– terminal
Figure 2 — N1313 Alternator with Regulator
Figure 1 — N1313 Alternator and
N3039 or N3222 Regulator Terminals
14 V B+
terminal
28 V B+
terminal



E terminal
 
AC terminal
(N3222 only)