LT-12PREG-1
7
Charles Industries, Ltd. All rights reserved. Printed in the United States of America.
Table 2. Suggested Wire Gauges
Wire Length (feet)
< 140 Amps
< 200 Amps
10
#6
#6
20
#4
#2
30
#2
#1
40
#1
#0
50
#0
#00
Table 3 shows all the signals available, whether or not they are required, and their function.
Table 3. Alternator Regulator Signals
Pin #
Signal Name Required
Function
1
PARALLEL
NO
An output that has a positive voltage when the regulator detects that the
house battery is being charged. The maximum load is 1.5 amps.
2
ON/OFF
YES
A positive voltage that turns the alternator field circuits of the regulator on.
Typically connected the the ignition switch or oil pressure switch. Typical
draw is 0.003 amps
Note:
On gasoline engines, do NOT connect to the ignition coil circuit.
Connect at the ignition switch.
3
GROUND
YES
The reference ground for the regulator. All battery voltages are referenced
to this wire. Connect this wire first.
4
B+
YES
The source of power for the alternator field current, PARALLEL, ERROR
lamp, and STATUS lamp. Amperage draw on this wire is the same as the
alternator field current: 15 amps maximum.
5
FIELD
YES
The wire driven positive by the regulator to make the alternator charge. Volt-
age at this point depends on how much current is being produced by the
alternator, and varies from zero to battery voltage.
6
ALT. GND
YES
The return line for field current.
Note:
Absence or loss of this connection will prevent charging. Do NOT
jumper this wire to the ground tab.
7
LOCK
NO
If connected to battery voltage, the regulator is locked at battery gassing
voltage, typically 13.8 volts. Used to prevent higher voltages when halogen
lights are being used. Removal of the lock signal causes the regulator to go
to the float setpoint.
8
BAT. VOLTS
YES
The sense wire for battery voltage. Any voltage drop in this wire from the
battery can cause overcharge.
9
T– (BLK)
NO
Ground side of the temperature sensor which is supplied with the regulator.
10
T+ (RED)
NO
Positive side of the temperature sensor. Voltage at T+ is 2.98 volts at 25
C, and varies plus and minus with temperature at the rate of 0.01 volts per
degree C. Some battery manufacturers require temperature sensing of the
battery for warranty purposes. In all cases (except for temporary trouble-
shooting) we recommend using the the temperature sensor at all times.
11
ABS
NO
A positive voltage at ABS will lock the regulator at the absorption setpoint.
Typically used with the Charles Industries Energy Management System.
12
ERR
NO
A positive going signal that provides troubleshooting information identical to
the red Error LED (see Table 6). Maximum current permitted from the ERR
output is 0.05 Amps.