Sterling Power Products AB1290 Remote DOM Sense 3 optional, Alternator Temp Sensor 2 optional

REMOTE DOM SENSE (3) (optional)

The connection leading to the positive terminal of the domestic battery. (See Extended Installation.) Installation is optional.

ALTERNATOR TEMP SENSOR (2) (optional)

Connection for the alternator temperature sensor. Installation is optional.

BATTERY TEMP SENSOR (1) (optional)

Connection for the battery temperature sensor. Installation is optional.

REMOTE CONTROL (5) (optional)

Connection for the optional remote control.

ALTERNATOR INPUT SHUNT (optional)

Connection for the alternator input shunt which is part of the remote control package.

STARTER BATTERY SHUNT (optional)

Connection for the starter battery shunt which is part of the remote control package.

UNIT EXPECTATIONS

What do I expect to see from this unit and why?

The below test was set up and monitored and is as close as possible as to what happens on the average split charge system. The engine battery is a 100 amp hr standard lead-acid, and the domestic battery is 3 x 100 amp hr standard lead-acid. The engine battery was discharged to 11 volts (about 10 engine starts) and the domestic bank to about 11 volts (will no longer run an inverter and is about 60% empty). The alternator used is a Bosch 90 amp with a standard 13.9 volt (variable) regulator. The unit battery type is programmed to open lead-acid. There are two graphs, one is showing the current going into the batteries, and the other is showing the various voltages on the system.

System Voltage Graph:

The key points to pick up on here are:

The yellow trace (alternator voltage into the unit) clearly shows that the system is doing its job. It is designed to pull this voltage down a little in order to enable the standard alternator regulator to produce its full current. You can clearly see that on position 4 on the voltage curve the voltage is pulled down to position 5 . The current has increased from position 8 - 9 which is about 70 amps improvement.

Position 1 : This is the magic point, the point where the domestic battery voltage exceeds the alternator input voltage.

This is what the process is all about.

The steps on the graphs show the unit boosting every 15 minutes, then resting for 2.5 minutes. An example of this is the time period between 2 and 3 . What you can see here is that by switching off the amplifier (to help the engine battery getting more charge), the engine battery voltage curve increases during that step shown at point 6 which results in extra current going into the engine battery at position 7 . The current change of this process is reflected in the other graph marked ‘the current graph’. The current graph shows the current flow into the engine start battery and the domestic system. The effect of the amplifier can be clearly seen when the unit switches off for its 2.5 minutes rest cycle. The current drops from position 9 = 95 amps to position12

=about 20 amps, a huge difference. At the same time you can see the extra current going into the starter battery which clearly charges through the whole exercise.

On completion the unit switches off, and the process continues as a conventional split charge system 10 . If however the domestic battery falls below 12 volts, the system will automatically restart and continue the process again.

11 shows that the engine battery has been fully charged and is taking no more current.

Engine battery bank, domestic battery bank, and alternator voltage curves

15.00																	2 3
	volts									Volts
14.50
																		6																																		10
14.00											4
				1										5																													alternator input voltage
13.50																																											starter battery voltage
																																											domestic battery voltage
13.00							TIME min.																		time in mins
12.50	9	18	28	37	46	55	64	73	83	92	101	110	119	128	138	147	156	165	174	183	193	202	211	220	229	238	248	257	266	275	284	293	303	312	321	330	339	348	358	367	376	385	394	403	413	422	431	440	449	458	468	477	486	495	504	513	523	532	541	550	559	568	578	587	596

Domestic battery bank current curve, with engine battery bank current curve

100								9
90														domestic battery current
80
														starter battery bank current
70
60	ampsAmps
50
40
30
20							8		12		7
10														11																		10
0	T im e		m i n .
							106	121	136	151	166	181	196	211	226	241	256	271	286	301	316	331	346	361	376	391	406	421	436	451	466	481	496	511	526	541	556	571	586
1	16	31	46	61	76	91

time in mins

5