Technical Smart alternator?
- Thread starter Cycle Guy
- Start date
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Technical Smart alternator?
For anyone else who wants to test their smart alternator I recommend one of these
Conventional ways of testing the alternator won't work.
You could be revving the engine when the van is stationary and the battery is draining because its over 80% charged.
Which leads you to think the alternator is faulty when there is nothing wrong with it.
You need to be able to see the voltage when you are driving
Look at the voltage when you take your foot off the throttle and the vehicle momentum is turning the engine - the voltage should rise noticeably.
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You could be revving the engine when the van is stationary and the battery is draining because its over 80% charged.
Which leads you to think the alternator is faulty when there is nothing wrong with it.
You need to be able to see the voltage when you are driving
Look at the voltage when you take your foot off the throttle and the vehicle momentum is turning the engine - the voltage should rise noticeably.
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theoneandonly
Established member
depending on motorhome convertor could be as late as 2020. Mercs had them from 2015. You dont need one for a b2b to be usefull. Remember if you have a split charge relay system you need to disable it when fitting a b2b2.
I've never had a b2b or solar panel so can't say how good they are.
My X2/50 (150a stahdard alternator) had a parallel connection between the main battery and the 2x100ah standard Lead Acid secondary batteries through a voltage sensing relay. But that would be no good with a smart alternator.
So my X2/90 (180a smart alternator) has a parallel connection between the main battery and the 4x100ah standard Lead Acid secondary batteries through a simple 200a relay control;ed by the ignition switch (can just get 2x019 100ah batteries under each X2/50 or X2/90 seat)
Both using hefty 25mm2 cable. I have a dashboard switch to disconnect the relay connecting the secondary batteries if ever they became so flat as to impede the main battery from starting the engine. But it has never happened yet.
It works fine and has been doing so for nearly 3 years. Takes my 510ah battery bank up to 15 volts with regenerative braking. Would need a huge b2b to handle that current? and it wouldn't provide all that free electricity from regenerative braking. Which is better for my pocket and the environment than a b2b.
But I can see neither system is perfect.
My X2/50 (150a stahdard alternator) had a parallel connection between the main battery and the 2x100ah standard Lead Acid secondary batteries through a voltage sensing relay. But that would be no good with a smart alternator.
So my X2/90 (180a smart alternator) has a parallel connection between the main battery and the 4x100ah standard Lead Acid secondary batteries through a simple 200a relay control;ed by the ignition switch (can just get 2x019 100ah batteries under each X2/50 or X2/90 seat)
Both using hefty 25mm2 cable. I have a dashboard switch to disconnect the relay connecting the secondary batteries if ever they became so flat as to impede the main battery from starting the engine. But it has never happened yet.
It works fine and has been doing so for nearly 3 years. Takes my 510ah battery bank up to 15 volts with regenerative braking. Would need a huge b2b to handle that current? and it wouldn't provide all that free electricity from regenerative braking. Which is better for my pocket and the environment than a b2b.
But I can see neither system is perfect.
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It looks like you have a well-established system) If your system can handle the flow of energy and has been working perfectly for almost three years, then perhaps you don’t need a big b2b.
