How can I boost leisure alternator output whilst using Travelpower to charge ?

[Bernie the Bolt]

Hi , I think Nicknorman can answer this -

I have a beta 43 ( 2006 long spline cranknose ) fitted with a Travelpower 3.5kva , powering a Victron 12/2500/120 whilst charging. I see about 100amps from the Victron , plus whatever the leisure alternator output , this starts at about 90amps , drops to 50 when the T.P. is switched on, but rapidly falls to 10-20amps.

As I have a hybrid LA/ Lifepo4 battery bank ,it can receive up to 200amps no problem,  so how can I make better use of the leisure alternator ? 

I am thinking a Sterling advanced alternator regulator could do it.

The L.alternator is a 175amp and rarely gets above 60 deg c.

[PeterF]

The info needed here is the voltage measured at the battery bank when you get the 90A, 50A and 10-20A points listed above.

[Bernie the Bolt]

OK , I will report back.

[Tracy D'arth]

1 hour ago, Bernie the Bolt said:

Hi , I think Nicknorman can answer this -

I have a beta 43 ( 2006 long spline cranknose ) fitted with a Travelpower 3.5kva , powering a Victron 12/2500/120 whilst charging. I see about 100amps from the Victron , plus whatever the leisure alternator output , this starts at about 90amps , drops to 50 when the T.P. is switched on, but rapidly falls to 10-20amps.

As I have a hybrid LA/ Lifepo4 battery bank ,it can receive up to 200amps no problem,  so how can I make better use of the leisure alternator ? 

I am thinking a Sterling advanced alternator regulator could do it.

The L.alternator is a 175amp and rarely gets above 60 deg c.

A vote for the Sterling. Many don't like them, I have fitted dozens and they do the job. Make sure that your cables are adequately sized, you get a lot of volts drop at 175 Amps if they are undersize. The Sterling will counter this due to it sensing battery voltage but if they are thin they will cook. Positives and negatives!

 

[nicknorman]

You must be dropping some voltage in the wiring between alternator and batteries. I would expect the standard Iskra 175A alternator to be putting the full 175A into the Li battery without any fancy controller. Ours did, anyway.

 

Check the voltage between the Iskra terminals (fat red B+ wire, and casing) and again at the battery terminals with engine running at 1200 rpm and the travelpower off. I suspect there will be a considerable difference. Then it is a matter of checking voltages along the route to see at what point the voltage drop is happening. For example the alternator may route through the battery isolator whereas the Victron probably doesn’t.

 

The other possibility is that there is a blown diode in the alternator, this would result in reduced output voltage. So tell us the alternator terminals voltage and current when charging without the travelpower.

 

The only need for something like a Sterling A2B is to REDUCE the current to avoid the alternator overheating!

Edited December 6, 2023 by nicknorman

[nicknorman]

As an aside to this I would just mention that you have to be quite careful with sustained high currents. It is very easy for something with a slight resistance to get very hot! Melted battery isolators etc! I use a BDS-A latching relay as the battery emergency disconnect, it is rated at 190A at 85C ambient and 260A at 25C ambient, but it still gets very hot at 200A sustained charging current.  Not sure what the margin to melted plastic is! Makes me a bit nervous so I tend to avoid charging at more than about 150A.

[Alan de Enfield]

50 minutes ago, nicknorman said:

Not sure what the margin to melted plastic is!

 

Nylon 6:6  (probably the most common general purpose grade) starts to soften at 85c, unless it has high temp fillers in the mix, when it can go to 105c

Nylon is 'totally liquid' at 220c to 265c depending on grade but speciality grades are available - ie PA46 has a melt temperature of 300c-330c

 

Once it has started to soften it is pretty useless for most things.

[IanD]

5 minutes ago, Alan de Enfield said:

 

Nylon 6:6  (probably the most common general purpose grade) starts to soften at 85c, unless it has high temp fillers in the mix, when it can go to 105c

Nylon is 'totally liquid' at 220c to 265c depending on grade but speciality grades are available - ie PA46 has a melt temperature of 300c-330c

 

Once it has started to soften it is pretty useless for most things.

Which is why components like high-current switches are unlikely to use general-purpose nylon 🙂

 

Unless they're cheap Chinese knock-offs, which could melt or burst into flame at any moment...

 

https://marinehowto.com/counterfeit-electrical-components-just-say-no/

Edited December 6, 2023 by IanD

[Alan de Enfield]

1 minute ago, IanD said:

Which is why components like high-current switches are unlikely to use general-purpose nylon 🙂

 

Unless they're cheap Chinese knock-offs, which could melt or burst into flame at any moment...

 

https://marinehowto.com/counterfeit-electrical-components-just-say-no/

 

We used the grade of any 'plastic' if it met the specifications - you cannot fault the product is it fails due to incorrect usage.

 

Many years ago we tended for the cable fixings for the new Sydney Monorail System and were competing on an international basis. We quoted based on materials that knew would be required as we had supplied the Australian market for many years and had our own offices and warehouse there.

 

We lost the tender on price. The successful company was a Taiwanese manufacturer.

 

Anyway, a couple of years later I had a call from our Sydney office saying there were huge problems with the monorail. 

 

Long-story-short

Opening day, fanfares, parties, speeches and the Mayor of Sydney and other local dignitories depart on the train for its inaugral circuit of Sydney. A couple of miles later and the train stops.

Fire engines called, ladders extended and the dignitaries make an undignified return to terra firma.

The cable fastenings had failed cables fallen off, connections broken etc etc.

 

Our local office was called in to assess the reason for the failures - the Taiwanese company had not supplied a product manufactured for the temperatures and sunlight found in Australia. We had quoted for Nylon with a 2% Carbon Black content to give the necessary UV protection.

 

We were awarded the contract to supply all of the fixings, and a rolling replacement programme was introduced.

 

Right material - right product for the application.

[Brian422]

One Forum contributor reduced alternator pulley size so that it would produce output at lower engine speed. 

[IanD]

1 hour ago, Brian422 said:

One Forum contributor reduced alternator pulley size so that it would produce output at lower engine speed. 

A good idea so long as the alternator doesn't then overspeed at maximum engine rpm...

[nicknorman]

2 hours ago, Brian422 said:

One Forum contributor reduced alternator pulley size so that it would produce output at lower engine speed. 

 

If the Beta setup is the same as ours, there is no need to and in fact it would be a bad idea. The alternator can already produce about 135A at idle and this is a big load on the crankshaft bearings/pulleys/belt etc. The engine, belt etc struggles a bit with this due to the high torque load. By about 1000 engine rpm the alternator can make nearly full output. If the engine pulley was made smaller, all of this would get worse and the engine would struggle more, the belt more prone to slippage and all for naught. If the system is working properly, it is excellent and no need to tinker. If it is not working properly the correct course of action is to fix the fault rather than do stuff to disguise the fault.

[wakey_wake]

On 06/12/2023 at 09:20, nicknorman said:

The other possibility is that there is a blown diode in the alternator, this would result in reduced output voltage. So tell us the alternator terminals voltage and current when charging without the travelpower.

An interesting possible failure mode!

 

I've not looked at alternator current on an oscilloscope, but since it's full wave rectified three phase then presumably one should see six overlapping half-sine peaks per alternator turn? About 1800 per second, if 1200 engine rpm * 2.5 pulley ratio * 6 peaks?

 

(I don't expect most folk diagnosing charging problems will want to bring an oscilloscope into the mix, but mine is just up the gangway. An exercise for later.)

~~ post join? ~~

 

On 06/12/2023 at 11:35, IanD said:

Which is why components like high-current switches are unlikely to use general-purpose nylon 🙂

I do look rather quizzically at some of these shunts I got.

The smaller ones are on a plastic base plate, and if that melts the next stop is ground. For a high-side shunt that's Bad News aka. let's see if the fuse works.

 

However I don't see any shunts on ceramic isolation, so I got some bare ones and will sort something.

 

OK the shunt should be protected by the fuse, as it is essentially part of the cable, but it's just a "deliberate" resistor as opposed to an "accidental / inevitable" resistor like the rest of the cable.

[Tony Brooks]

26 minutes ago, wakey_wake said:

OK the shunt should be protected by the fuse, as it is essentially part of the cable, but it's just a "deliberate" resistor as opposed to an "accidental / inevitable" resistor like the rest of the cable.

 

The shunts are also very low resistance and because of their use designed to pass full current without overheating. They also have no moving parts once properly installed, unlike many switching components. Really it is as Alan said, selecting the correct material for the job and for shunt mounts I am sure nylon is fine.

 

You will definitely see a missing phase on the scope, you can usually see them when just connected to the battery, but not so sure with Li in the mix, but I would expect so.

 

I wonder if the Travelpower is delivering a higher charging voltage than the alternator so the alternator regulator is working, but then the Li should still be pulling maximum current and dragging the alternator charging voltage down.

 

Edited to add, no point in trying to count peaks because they keep coming, just look for missing ones.

Edited December 7, 2023 by Tony Brooks

[Tracy D'arth]

2 minutes ago, Tony Brooks said:

 

The shunts are also very low resistance and because of their use designed to pass full current without overheating. They also have no moving parts once properly installed, unlike many switching components. Really it is as Alan said, selecting the correct material for the job and for shunt mounts I am sure nylon is fine.

 

You will definitely see a missing phase on the scope, you can usually see them when just connected to the battery, but not so sure with Li in the mix, but I would expect so.

 

I wonder if the Travelpower is delivering a higher charging voltage than the alternator so the alternator regulator is working, but then the Li should still be pulling maximum current and dragging the alternator charging voltage down.

I am curious, does not the Travelpower have to feed a battery charger to be used to charge the batteries? If so, is the battery charger output higher than the alternator regulator setting and is therefore causing the said regulator to reduce the charging from the alternator?

Why use both together when one would suffice?

[Tony Brooks]

3 minutes ago, Tracy D'arth said:

I am curious, does not the Travelpower have to feed a battery charger to be used to charge the batteries? If so, is the battery charger output higher than the alternator regulator setting and is therefore causing the said regulator to reduce the charging from the alternator?

Why use both together when one would suffice?

 

I think because he wants more charge into the Lis so he can shorten the engine run time.

[Tracy D'arth]

Just now, Tony Brooks said:

 

I think because he wants more charge into the Lis so he can shorten the engine run time.

I would expect one regulator to fight the other like a solar regulator fights an alternator regulator.

[nicknorman]

5 minutes ago, Tracy D'arth said:

I am curious, does not the Travelpower have to feed a battery charger to be used to charge the batteries? If so, is the battery charger output higher than the alternator regulator setting and is therefore causing the said regulator to reduce the charging from the alternator?

Why use both together when one would suffice?

To charge faster as Tony says. The regulation curves on both the Victron and the alternator are quite soft and so they will share the load unless the set voltages are way out. I do this sometimes when I want to charge fast - the Iskra, once it has settled down at 90C is limited by my controller to around 125A. The Mastervolt Combi I have set to limit at 60A so I can put in 185A without overheating either device.

But if I start from cold and whack up the Mastervolt current limit to 100A, I could put in 285A. The Li will take that without breaking into a sweat, the voltage will still be down at around 13.5v

2 minutes ago, Tracy D'arth said:

I would expect one regulator to fight the other like a solar regulator fights an alternator regulator.

That is a myth. It doesn't happen.

[Tony Brooks]

Just now, Tracy D'arth said:

I would expect one regulator to fight the other like a solar regulator fights an alternator regulator.

But remember the Lis will draw maximum charge, so pulling the charging voltage down. In that situation, the alternator regulator should be doing nothing. However, I suspect that is a recipe for a cooked alternator in short time.

[Bernie the Bolt]

On 05/12/2023 at 19:50, PeterF said:

The info needed here is the voltage measured at the battery bank when you get the 90A, 50A and 10-20A points listed above.

90 + amps - voltage = 13.1 ( just after starting b4 TP engaged )

44 amps - voltage = 13.7 ( after TP engaged )

10- 20 amps - voltage 13.85 tp 13.95 

[Tony Brooks]

My opinion is that there is a good chance you have a main diode failed. It is the lase reading that makes me suspect that, unless there is a connection or cable size problem on the charging circuit.

Edited December 9, 2023 by Tony Brooks

[Bernie the Bolt]

On 07/12/2023 at 19:31, Tracy D'arth said:

I am curious, does not the Travelpower have to feed a battery charger to be used to charge the batteries? If so, is the battery charger output higher than the alternator regulator setting and is therefore causing the said regulator to reduce the charging from the alternator?

Why use both together when one would suffice?

You are correct , I am using a victron multiplus to charge when the TP is on , but with 300 ah of Lifep04 ( 2 x150 ) they are capable of accepting 2x100amp charge , just trying to reduce engine hours / diesel. ( In the winter, summer is not an issue with our solar array 830w.) 

[PeterF]

Definitely something not right. My Beta 43 with 175A alternator is getting towards 14.5V when the amps around 20. I agree it is likely to be an alternator issue but to make sure it is not voltage drop in the cables. Next time you are running measure the voltage at the battery and at the alternator, between the main positive cable terminal and the case. If the two voltages are similar your alternator is not generating enough voltage and needs looking at. If the alternator voltage is 14.5V or thereabouts try and find where the voltage drop is occurring by measuring the voltage at each connection between the battery and alternator.

[Tony Brooks]

1 minute ago, PeterF said:

Definitely something not right. My Beta 43 with 175A alternator is getting towards 14.5V when the amps around 20. I agree it is likely to be an alternator issue but to make sure it is not voltage drop in the cables. Next time you are running measure the voltage at the battery and at the alternator, between the main positive cable terminal and the case. If the two voltages are similar your alternator is not generating enough voltage and needs looking at. If the alternator voltage is 14.5V or thereabouts try and find where the voltage drop is occurring by measuring the voltage at each connection between the battery and alternator.

 

Alternatively, connect the voltmeter alt .B+ to Bat pos. and rev the engine. The meter will read the volt drop on the main circuit which is in parallel to the meter. Then do the same for the negative side.

 

Do whichever is easiest.

 

Ideally, the maximum volt drop should be around 0.3 volts. If you have more, just step one of the voltmeter leads along the circuit connections until you suddenly lose a lot of the volt drop.

[Bernie the Bolt]

The voltages I have quoted are taken from a smartguage which is connected across the battery terminals. 

I will report back with other suggested readings.