Beefy AUX alternator installed. No power pulling away, then surge of power. Normal?
- Thread starter WT1J
- Start date
Makes sense. I've sent Nations an email to try to find out if they think a clutch is needed and whether it's an option. This alternator apparently also has an option to detune it so that it produces less current (and load) at engine idle and then ramps it up as the RPMs increase. I've asked them if this is an option and for more info. It may provide us with more power during initial pull away while the alternator is producing current.
The van has an unusually high battery capacity and unusually high power delivery capability. It's a 800AH bank of 24 volt batteries. Equivalent to 1600 amp hours at 12 volts or 19,200 watt hours.
We have the ability to pull 8,000 watts continuously from the batteries with 10,000 watts peak We're using dual Victron Quattro inverters:
amsolar.com
It's a film truck with quite a few 20 amp AC circuits inside and out that let us fully utilize the available power. So it's quite possible for us to run them down to zero in just over 2 hours.
At 3KW alternator output it'll take over 6 hours to charge them up assuming 100% efficiency, so maybe more like 9 hours.
Typical use will be driving to shoot location, parking and turning off van. Using the heck out of the batteries and hopefully not running out of juice. Then packing up and driving to home base. Supplementing any remaining charge time needed with shore power on arrival back at home base.
She'll be doing quite a lot of highway miles for remote shoots - over 1000 mile trips regularly. So we may see for example a 6 to 9 hour charge time for an entire day trip leg. And then have that scenario repeat fairly often.
~Mark.
Edited for clarity.
We have the ability to pull 8,000 watts continuously from the batteries with 10,000 watts peak We're using dual Victron Quattro inverters:
Quattro 5000 Inverter/Charger
Similar to the MultiPlus, the Quattro is also a combined inverter and charger. Additionally, it can accept two AC inputs and automatically connect to the active source. Its many features include a true sine wave inverter, adaptive charging, hybrid PowerAssist technology plus multiple system integra
amsolar.com
It's a film truck with quite a few 20 amp AC circuits inside and out that let us fully utilize the available power. So it's quite possible for us to run them down to zero in just over 2 hours.
At 3KW alternator output it'll take over 6 hours to charge them up assuming 100% efficiency, so maybe more like 9 hours.
Typical use will be driving to shoot location, parking and turning off van. Using the heck out of the batteries and hopefully not running out of juice. Then packing up and driving to home base. Supplementing any remaining charge time needed with shore power on arrival back at home base.
She'll be doing quite a lot of highway miles for remote shoots - over 1000 mile trips regularly. So we may see for example a 6 to 9 hour charge time for an entire day trip leg. And then have that scenario repeat fairly often.
~Mark.
Edited for clarity.
VanGoSki
Well-known member
Wow, that's pretty cool. Is all that power for video lighting? Or maybe satellite transmission? I figured you had about half that amount of storage.
I believe you can expect your efficiency to be 100% with this setup. Unless I'm missing something, your batteries will have a direct connection to your alternator so there are no losses to factor in. 100 amps generated will be 100 amps stored.
I believe you can expect your efficiency to be 100% with this setup. Unless I'm missing something, your batteries will have a direct connection to your alternator so there are no losses to factor in. 100 amps generated will be 100 amps stored.
Thanks. Yes it's mostly for lighting, which has become much more efficient since LEDs have gotten to a point where they are good enough (have a high enough CRI/TLCI for film). Used to be that you'd need a generator truck to power 12 kilowatt units. Also it will have on the road production capability with a little workstation inside the van and that needs power. But the majority is lights and other on-set power like powering video village.
The van isn't for live broadcast - it's for film making. And so no live satellite links.
Yeah agreed that the efficiency will be better than I indicated - we are running lithium and that's pretty much linear when charging up compared to lead acid. So it's mostly down to resistance in terms of losses I'd think.
The van isn't for live broadcast - it's for film making. And so no live satellite links.
Yeah agreed that the efficiency will be better than I indicated - we are running lithium and that's pretty much linear when charging up compared to lead acid. So it's mostly down to resistance in terms of losses I'd think.
autostaretx
Erratic Member
If i'm reading the photos correctly, your green belt is (properly) coming from a second pulley sheave on the crankshaft.
The "sprag clutch" is to allow the alternator(s) to *continue to coast* when the engine slows down abruptly.
It does not affect "push back" (which i translate as "resistance to forward motion").
By allowing the alternator to coast, it's not reversing the direction of "power flow" that the belt is carrying.
(switching from "engine pulling alternator" to "alternator pushing belt to try to get the engine to go faster")
Many of the "wrap angles" and tensioner designs are not really prepared for that reversal.
For a dedicated belt like the Nations', it's probably OK. (versus the "powers everything" serpentine)
--dick
p.s. although i'm an electrical engineer, i'm well aware of the mechanical engineers' credo of "F=M*A" and "you can't push a string"
The "sprag clutch" is to allow the alternator(s) to *continue to coast* when the engine slows down abruptly.
It does not affect "push back" (which i translate as "resistance to forward motion").
By allowing the alternator to coast, it's not reversing the direction of "power flow" that the belt is carrying.
(switching from "engine pulling alternator" to "alternator pushing belt to try to get the engine to go faster")
Many of the "wrap angles" and tensioner designs are not really prepared for that reversal.
For a dedicated belt like the Nations', it's probably OK. (versus the "powers everything" serpentine)
--dick
p.s. although i'm an electrical engineer, i'm well aware of the mechanical engineers' credo of "F=M*A" and "you can't push a string"
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Yes thanks. I understood this to be the case. Sorry if I gave you the impression I thought my alternator was going to assist my engine or something along those lines. Understood that the goal is to reduce wear on the belt by allowing coasting.
Eric Experience
Well-known member
Wti.
You should get a sprag fitted, the sprag is not there for sudden slowing of the alternator, that is a common misunderstanding, the crank is like a torsional spring it flexes back on compression and then flexes forward on firing, the angles are only a few degrees but it happens twice in each revolution, typically 8 thousand times a minute, that generates a lot of heat and loss of efficiency. you have paid good money to get this installation you should get it done correctly. It is a sad fact that companies will try to take short cuts and rely on there customers to do the quality control. Eric.
You should get a sprag fitted, the sprag is not there for sudden slowing of the alternator, that is a common misunderstanding, the crank is like a torsional spring it flexes back on compression and then flexes forward on firing, the angles are only a few degrees but it happens twice in each revolution, typically 8 thousand times a minute, that generates a lot of heat and loss of efficiency. you have paid good money to get this installation you should get it done correctly. It is a sad fact that companies will try to take short cuts and rely on there customers to do the quality control. Eric.
Boxster1971
2012 Sprinter 3500 Ext
Mark - is your van really a 2021 model or a 2020. Several threads on this forum indicate the V-6 diesel and 4X4 are not yet available on the 2021 models. Searching various dealer inventories in my area - I could find no 2021 models, only 2020.
Edit: Just saw your answer in another thread - you have a 2020 model as I thought.
2021 Sprinter | Sprinter-Source.com (sprinter-source.com)
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Beach2Snow
New member
Hi Mark, I don't mean to de-rail the conversation.
I am building a similar set up (not nearly as big) using the nation's 24v dual alternator.
I am assuming you are using the Balmar MC-624. Can you share what other components you are using to communicate with and monitor the alternator charge rate?
I am building a similar set up (not nearly as big) using the nation's 24v dual alternator.
I am assuming you are using the Balmar MC-624. Can you share what other components you are using to communicate with and monitor the alternator charge rate?