G
Guest
Guest
I now risk the wrath of those that know a lot better than me when it
comes to running spotlamps etc. on vehicles. But I have put extra
lamps on plant and equipment and as long as they were used with the
engine running the standard alternator coped with - it seemed - just
about anything.
But when it comes to running auxiliaries then you don't always have
the engine running and you need reserve power. And of course the
route to travel is via an extra battery/s. Some of the best systems I
have seen on a TLC have been on the 75 troopies used as de-mining
team ambulances where they have a lot of technical gear as well as
huge Warn winches. The systems used for these extras are a whole new
world from the usual auto system.
For over 25 years I have owned boats where the electrical circuit is
a critical part of the internal systems. Countless times I have heard
people complain that they need a higher power alternator, yet what
they need is to apply thought on what they want to get out of it and
how they will use it, and re-think their whole system.
In my boat I have 15 cabin lamps (fluorescent - some with 3 X 8w
tubes, tungsten and halogen), 1 halogen spotlamp and a combination
navigation light, two water pumps for domestic supply and shower pump
out, and a full size Lec domestic fridge with a 12v Bosch compressor
motor. Plus a 700w quasi sinewave inverter to run the TV, video,
radio and pc when cruising. All I need is 2 hours 15 minutes running
each day to be completely self-contained with power for another day
or so, yet that is with all systems working and no power saving
regimes - and I have a 55w alternator to power it all. This runs on a
slow revving dagga dagga dagga type of engine which at most when
cruising reaches 1000rpm.
I have two battery circuits, one 95ah starter battery, and 3 X 120ah
batteries in parallel to power the domestic system, all kept charged
by that one small alternator.
The key to getting the most out of your alternator is to make sure it
is getting the right message from the system to ensure it puts out
the power, and then give it a chance to achieve its potential output.
There is the rub, automotive systems nearly always have a machine
sensed system which closes the alternator's output down as soon as
the voltage at the alternator rises to about 14.4v. In most cases
that voltage is the 'surface' voltage of that sent back to the
regulator from the battery plates. Unfortunately the voltage is not
'soaked' through those plates to full charge.
So by all means fit an auxiliary battery, but make sure its a deep
cycle or at least a 'leisure' type. This will cope with constant
power draw for prolonged periods, they do not have a high cranking
capacity as do starter batteries. My 3 domestic batteries are of the
deep cycle type. But fitting an extra battery with a split charge
relay is not the end of the answer to the problem.
Next, make sure the alternator runs at near maximum speed as much as
possible. My little alternator runs at a ratio of about 6 to 1 to the
crank pulley. I had a mate make me a super small alternator drive
pulley as its a Magneti Marelli alternator and they are a bit
rare/obsolete. But smaller pulleys are available off the shelf from
auto electricians for the more common makes of alternator. Just
remember that you may need shorter drive belts - and fit a matched
pair (maybe an 8 digit manufacturing batch number stamped on the
outside surface, that should be the same on each) .
Finally, change the sensing of the system by buying a split charge
relay or diode splitter, and an alternator controller. I see - I
think - Roman suggested viewing the Adverc webpage. Its a good make
of controller but somewhat over the top, even for a boat, as they are
made more for emergency vehicles and are very technical. So look for
something a little more simple, and some overland equipment
preparation companies have alternatives, though a bit expensive.
The output of the alternator goes to the splitter and one of its
output leads goes straight to the starter via an ammeter, and
voltmeter if you want. That circuit will look after itself just as
the alternator manufacturer intended in a normal vehicle system.
The other output from the splitter takes a route described by the
controller manufacturer, which can vary but is usually quite
straightforward, it is the signal sent to the output of the
alternator that is the important part of the circuit. To achieve this
there are usually another 4 wires coming from the controller that
have to be connected to their instructions.
I have had a high tech 'Kestrel' made by Acorn engineering in Denton
Manchester (cost today about 130 quid), its efficient and can be
adjusted manually so you can tweak the volts up to 15 before it cuts
out. When fitting it you have to solder a wire to one of the
alternator brushes to connect to the controller. The final adjustment
of its output is related to the maximum output of the alternator in
relation to the battery capacity of the system in total. This in
order not to overheat the alternator or boil the batteries unncessarily.
I have now gone digital with a controller made by Sterling Power
Products of Worcester, again costing 130 quid. This is as good as the
Kestrel but more so. It has a facility to set it to the type of
battery cell it is controlling - though they recommend ordinary wet
acid cell types if possible - hence power output. It self senses the
a.h. capacity of the batteries it has to charge. It also has a
battery temperature sensor that you put directly onto a terminal of
the battery bank you are sensing and controlling. It also has a 4
stage charging cycle which builds-up its output. It also has
safeguards for over voltage etc. etc. But there are no user friendly
adjustments. Again, a cable has to be soldered onto one of the
alternator brushes.
When fitted-up correctly it all looks after itself, but it is
advisable to check battery acid level regularly. When I start the
engine, yes, the alternator whistles, and if the belt is not tight
enough it can slip. But an old cambelt tensioner rigged to tension
the belt and give more 'wrap' to the alternator pulley solves that
possibility. (I am not in a position to put twin pulleys or a polyvee
pulley on the crankshaft unfortunately). The combined reading from
the ammeters gets up to about 48 amps, but not very often. The engine
start circuit soon charges and the usual 10 amps on that circuit soon
drop to just on the plus side of the dial. The alternator whistle
will die away in proportion to the gaining charge. But I usually
cannot hear it after 10 minutes. The controller also has a self
regulating 'float' facility to meet any load applied when the engine
is running but after the battery systems have charged.
All this gear is out there, but you don't solve the problem by
putting on a higher rated alternator, or even adding another battery
to your truck, its a lot more complicated than that but simple to
apply - if that's not a contradiction.
The instructions for the Sterling controller are a scream to read.
One day when Julian and I arranged to meet I showed him the crazy -
but entertaining - instructions. Maybe he will let me write out a few
quotes from them one day.
I think I have written enough, but just wanted to provoke some thought.
Cheers
Jon
Grand Union Canal
'92 HZJ80 ex UN surplus from Bosnia
comes to running spotlamps etc. on vehicles. But I have put extra
lamps on plant and equipment and as long as they were used with the
engine running the standard alternator coped with - it seemed - just
about anything.
But when it comes to running auxiliaries then you don't always have
the engine running and you need reserve power. And of course the
route to travel is via an extra battery/s. Some of the best systems I
have seen on a TLC have been on the 75 troopies used as de-mining
team ambulances where they have a lot of technical gear as well as
huge Warn winches. The systems used for these extras are a whole new
world from the usual auto system.
For over 25 years I have owned boats where the electrical circuit is
a critical part of the internal systems. Countless times I have heard
people complain that they need a higher power alternator, yet what
they need is to apply thought on what they want to get out of it and
how they will use it, and re-think their whole system.
In my boat I have 15 cabin lamps (fluorescent - some with 3 X 8w
tubes, tungsten and halogen), 1 halogen spotlamp and a combination
navigation light, two water pumps for domestic supply and shower pump
out, and a full size Lec domestic fridge with a 12v Bosch compressor
motor. Plus a 700w quasi sinewave inverter to run the TV, video,
radio and pc when cruising. All I need is 2 hours 15 minutes running
each day to be completely self-contained with power for another day
or so, yet that is with all systems working and no power saving
regimes - and I have a 55w alternator to power it all. This runs on a
slow revving dagga dagga dagga type of engine which at most when
cruising reaches 1000rpm.
I have two battery circuits, one 95ah starter battery, and 3 X 120ah
batteries in parallel to power the domestic system, all kept charged
by that one small alternator.
The key to getting the most out of your alternator is to make sure it
is getting the right message from the system to ensure it puts out
the power, and then give it a chance to achieve its potential output.
There is the rub, automotive systems nearly always have a machine
sensed system which closes the alternator's output down as soon as
the voltage at the alternator rises to about 14.4v. In most cases
that voltage is the 'surface' voltage of that sent back to the
regulator from the battery plates. Unfortunately the voltage is not
'soaked' through those plates to full charge.
So by all means fit an auxiliary battery, but make sure its a deep
cycle or at least a 'leisure' type. This will cope with constant
power draw for prolonged periods, they do not have a high cranking
capacity as do starter batteries. My 3 domestic batteries are of the
deep cycle type. But fitting an extra battery with a split charge
relay is not the end of the answer to the problem.
Next, make sure the alternator runs at near maximum speed as much as
possible. My little alternator runs at a ratio of about 6 to 1 to the
crank pulley. I had a mate make me a super small alternator drive
pulley as its a Magneti Marelli alternator and they are a bit
rare/obsolete. But smaller pulleys are available off the shelf from
auto electricians for the more common makes of alternator. Just
remember that you may need shorter drive belts - and fit a matched
pair (maybe an 8 digit manufacturing batch number stamped on the
outside surface, that should be the same on each) .
Finally, change the sensing of the system by buying a split charge
relay or diode splitter, and an alternator controller. I see - I
think - Roman suggested viewing the Adverc webpage. Its a good make
of controller but somewhat over the top, even for a boat, as they are
made more for emergency vehicles and are very technical. So look for
something a little more simple, and some overland equipment
preparation companies have alternatives, though a bit expensive.
The output of the alternator goes to the splitter and one of its
output leads goes straight to the starter via an ammeter, and
voltmeter if you want. That circuit will look after itself just as
the alternator manufacturer intended in a normal vehicle system.
The other output from the splitter takes a route described by the
controller manufacturer, which can vary but is usually quite
straightforward, it is the signal sent to the output of the
alternator that is the important part of the circuit. To achieve this
there are usually another 4 wires coming from the controller that
have to be connected to their instructions.
I have had a high tech 'Kestrel' made by Acorn engineering in Denton
Manchester (cost today about 130 quid), its efficient and can be
adjusted manually so you can tweak the volts up to 15 before it cuts
out. When fitting it you have to solder a wire to one of the
alternator brushes to connect to the controller. The final adjustment
of its output is related to the maximum output of the alternator in
relation to the battery capacity of the system in total. This in
order not to overheat the alternator or boil the batteries unncessarily.
I have now gone digital with a controller made by Sterling Power
Products of Worcester, again costing 130 quid. This is as good as the
Kestrel but more so. It has a facility to set it to the type of
battery cell it is controlling - though they recommend ordinary wet
acid cell types if possible - hence power output. It self senses the
a.h. capacity of the batteries it has to charge. It also has a
battery temperature sensor that you put directly onto a terminal of
the battery bank you are sensing and controlling. It also has a 4
stage charging cycle which builds-up its output. It also has
safeguards for over voltage etc. etc. But there are no user friendly
adjustments. Again, a cable has to be soldered onto one of the
alternator brushes.
When fitted-up correctly it all looks after itself, but it is
advisable to check battery acid level regularly. When I start the
engine, yes, the alternator whistles, and if the belt is not tight
enough it can slip. But an old cambelt tensioner rigged to tension
the belt and give more 'wrap' to the alternator pulley solves that
possibility. (I am not in a position to put twin pulleys or a polyvee
pulley on the crankshaft unfortunately). The combined reading from
the ammeters gets up to about 48 amps, but not very often. The engine
start circuit soon charges and the usual 10 amps on that circuit soon
drop to just on the plus side of the dial. The alternator whistle
will die away in proportion to the gaining charge. But I usually
cannot hear it after 10 minutes. The controller also has a self
regulating 'float' facility to meet any load applied when the engine
is running but after the battery systems have charged.
All this gear is out there, but you don't solve the problem by
putting on a higher rated alternator, or even adding another battery
to your truck, its a lot more complicated than that but simple to
apply - if that's not a contradiction.
The instructions for the Sterling controller are a scream to read.
One day when Julian and I arranged to meet I showed him the crazy -
but entertaining - instructions. Maybe he will let me write out a few
quotes from them one day.
I think I have written enough, but just wanted to provoke some thought.
Cheers
Jon
Grand Union Canal
'92 HZJ80 ex UN surplus from Bosnia