Mower based MV electrical design question

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Mower based MV electrical design question

Postby Shoeshine » Thu Feb 13, 2014 12:14 am

OK so the donor vehicle for the 2014 small MV has been acquired... a grasshopper commercial zero turn mower.

23hp Briggs and Stratton ELS series engine driving two hydrostatic wheel motors. Drive train all settled. (well at least in progress)

Now comes the lighting question i.e. night licensing. The machine in question has a charging circuit, consisting of a multi-pole ring with coils of wire that is mounted inside the flywheel. Not something I have ever dealt with. As I understand it, this is just sufficient to keep the onboard 12v sealed battery charged for starting. No manual or specs that I have been able to find. I do however, want to create some lighting effects sufficient to illuminate this beast. I have on hand a couple of power chair batteries (12v 40amp hour each) that I am envisioning running the nighttime lights. I have removed the mower deck, as it is not in use for this MV. There is now a V-belt pulley available for use out of the underside of the engine(used to run the mower blades)

What is the feasibility of adding an alternator to keep a charge on these batteries?

I can do EL wire off these two batteries and last the week with a charge or two in camp. Downside being kind of dim. Would rather run a series of cold cathode bars like the stuff used in computer case mods, or similar lighting elements to get a brighter effect. Something with a significantly larger draw.

So my question is multi tier, can the type of charger on board adequately charge a couple more batteries wired in series? If not, is there an easily adaptable alternator that I could attach to the mower blade belt that would work? Sources? cost? How difficult is this build? (I am mechanically proficient, electrically not so much)

Regardless, this is in design stage. Maybe I am not thinking on this in the right way. Alternate ideas (no pun intended) welcomed.
Any thoughts or even links to more research would be greatly appreciated.

Thanks in advance
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Re: Mower based MV electrical design question

Postby GreyCoyote » Thu Feb 13, 2014 5:57 am

The charger you describe is rated about 10 amps total. It is only designed to power the blade clutch and recharge the starting battery. It isnt suitable for lighting, so you will need a real alternator.

If you want quiet, reliable power, consider building a small Honda/Yamaha/Etc generator into your design. These are very quiet and can put out far more juice than an alternator. Plus you can use them for power when you are back at camp. But if you want an alternator, GM makes one that has a built-in regulator and exposes just a single terminal (power output). Thses are available from 65 to over 200 amps and are bidirectional units (turn either way and it makes power).

Suggestion: the engine is designed to run at high throttle to cut grass, but you are not cutting grass. Drop the speed a bit for playa use and get better mileage. The limiting factor will be cooling. Spin it too slow under load and you will burn it up. There should be a sweet spot at about 2/3rds throttle where it will be happy and cut both noise and fuel use considerably.

Make provisions to blow the cooling fins out with compressed air. The playa dust will gleefully find any oily surface and coat it completely. Briggs mills are notorious leakers. You have been warned. :mrgreen:

Good luck! Sounds like an awesome bit of mischief is in the making!
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Re: Mower based MV electrical design question

Postby Shoeshine » Sun Feb 16, 2014 10:57 pm

Thanks Grey, appreciate the input.

We already have a Honda eu2k in camp so I'm not sure getting another for the MV would be the best bang for the buck. I have seen some knock-offs (talon, Honeywell, etc..) around 800-1000w in the $300 range. Anyone with experience with these? I understand that they will be noisier... but we are talking about something on an MV already making a fair bit of engine noise, not something running at 5AM in camp.'

have done some more research and have found several automotive models to be had for chump change ($20 at the U-pull it)

SO my question morphs into, alternator salvaged for next to no money but a more extensive build. or a turn key generator with more noise. also direct wire the genny to the lighting? or build in a battery to keep the light on when parked. what's needed in terms of a charge controller if I put the batteries inline?

thanks again,
Shoe

P.S. Good call on the throttle. I am already noticing that with the mower deck (and consummate power use) gone, I need to throttle the thing back, not only for fuel usage, but also for pure noise and "jerking" off a start.
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Re: Mower based MV electrical design question

Postby BBadger » Sun Feb 16, 2014 11:18 pm

You could also buy some deep-cycle batteries for the MV, and use the genny back at camp to charge them during the day. You'll have to budget your power at night though. Those cold cathodes use like 0.3Amp each; LED strands use quite a bit too.
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Re: Mower based MV electrical design question

Postby name redacted » Sun Feb 16, 2014 11:19 pm

You said jerking off....

Anyway, an alternator needs to spin at a fairly high rpm to be efficient. The question would be where you could run it from. You may need to overdrive it to get the rpm necessary.

I like the generator idea...
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Re: Mower based MV electrical design question

Postby Colonel Monk » Sat Mar 22, 2014 2:52 pm

Howdy Shoeshine!!!

OK, look!!!

You are on the right track. First of all, here's a few pros/cons to help you make your decision:

Genny
-PROs: can run lights, charge battery, run stereo, AT ALL TIMES without running the main motor. This could be helpful for you if you are going to be parked alot (which you likely will be) or want to set up a dance party in the deep playa or whatever. Also a secondary source of power, should you have trouble with your charging circuit on the mower.
-CONs: $$$expense. There's really no other cons, assuming you are talking about a honda-style generator invertor. Don't even bother with the other style gennys that have to run full steam 3600 RPM at all times to create 120V @ 60 Hz. They suck, you do not want one on your MV.

Alternator
-PROs: with a few hundred bucks and some know-how, you can solve your power issues with what you already have. MUTANT COOL!!!!! Who says you should always take the easy way out?
-CONs: depending on the size of your power needs, battery bank, etc, you might need to leave your MV engine running to produce power. Waste of Fuel, Overheating, etc? Wild Card.... You never know how an engine like that will react to the playa...

Now - with 23hp, I'd say, you have PLENTY of power available to drive an alternator. And, with a PTO lever you can use to engage/disengage the alternator, you can disengage to get the motor running (cars do this automatically) and you can also use gauges for voltage and amperage draw to determine when you need it connected and when you don't. PERFECT.

A little googling, says that alternators are a little better than 50% efficient. So, lets say we buy a GM 100 amp alternator. Output from Voltage regulator to charge a battery is around 14.5 volts. 14.5v x 100A = 1450 Watts of power.

At efficiency of 50% (these are mechanical losses, friction, etc) 1450W / 50% = 2900W - this is the amount of power required to drive the alternator.

Now, 1 horsepower is equal to 750 Watts. So here we go: 2900W x 1HP/750W = 3.86 HP or roughly 4 HP.

I guarantee, that spinning the mower blades in thick wet grass took at least half of the motor's horsepower, so no doubt you have plenty of power to do this. Just think, a 22 inch mower has 5-6HP these days, so double that or more and you get the idea.

Some other basics: A single 12V Battery of the Marine/RV - Starting/Deep-Cycle variety has a capacity of about 85 amp-hours (Ah). This means, it can put out 85 amps of power in one hour before it's dead (it will always be less) or it can produce much more power than that over time at a lower load - say like, 10A-20A.....

So what kind of power will you draw? Depends. I don't know what kind of MV you are planning to build, but I have built one electric and have worked on many others. Last year, I did a bunch of work on my friends Death Hearse. Totally rewired the MV part.

Main power draws are: Headlights, Stereo, Taillights/Running Lights, AC Inverter (to run flame effects), and interior LED lamps. Yes, of course you need a stereo!!!!

If I was you, I'd get two of these batteries wired in parallel to ensure you have plenty of juice. This will let you run your lights and stereo when you are parked and NOT running the engine. I have had two of these batteries from Costco that have lasted since 2006 and they are still running strong. About 60/70 bucks each.

Now, name redacted has a point. In spite of adding a second battery to the death hearse to run the peripherals, we still had problems with the motor battery running dead. Since the GIANT cadillac motor is running at idle speed all over BRC, that particular alternator isn't spinning fast enough in BRC to make a charge!! We are sick of this problem. You might have it too.

So what to do?

Well, you will need to figure out what is the sweet spot for RPM on your MV motor, and then find out what is an appropriate RPM for your alternator for good output.

First, the motor RPM - drive it around and figure out what feels right, preferably with the sort of load you'll have on playa. Now, you need to measure the RPM of the PTO drive pulley on the mower. HOW?? With one of these cheap optical tachometers: http://www.amazon.com/AGPtek%C2%AE-Professional-Digital-Tachometer-Contact/dp/B004Q8L894/ref=sr_1_4?ie=UTF8&qid=1395522976&sr=8-4&keywords=optical+tachometer Simply put a piece of relective tape (included) on the pulley, and Voila!!

Second, once you have chosen the alternator you will use, look up the performance curve for the alternator - this is a simple graph, showing you what shaft RPM of alternator will get you X amps of charging power. Example:
Image

OK, how to use this info? Let's say we have the alternator with the purple curve, it's closest to our 100A (but keep in mind, you need the curve for YOUR alternator!!) so the curve starts to flatten out at around 4000 RPM, is flatter at 5000, and ends at 6000. Let's use 5000 RPM for our alternator.

Let's say, with the tachometer we measured the cruising RPM of the mower engine at 2500 RPM - at the PTO pulley we will use to drive the alternator.

We need to covert this 2500 RPM to about 5000 RPM on the alternator - how will we do this? Gear Ratios. Say we measure the diameter of the PTO pulley at 6 inches. If we were to use the same size pulley on the alternator, we'd have the same speed as the engine - but we need twice the RPM. We can get that, by reducing the size of the pulley on the alternator. The ratio that we need, is 2 to 1 (2:1) gear ratio. So if the PTO pulley is 6 inches, we need a 3 inch pulley on our alternator.

What alternator to use? Well, I know that I've read posts in the MV forum form Cap'n Goddammit where he swears by a certain alternator that is powerful and widely available at pick/pull junkyards. He says that the dust regularly takes them out, so he always has a few spares for the week. Only trouble there, is you need to make sure you know what model it is to get the right performance curve, or someone's say so as to what RPM you should run.

The type that you want, without a doubt, is what is called a "one-wire" alternator - these have the voltage regulator on board so that you are always putting out a charge voltage around 14.5 volts. All you do is connect the wire to the positive on the battery bank, and ground it to the battery and you're set.

Hope this helps.

CM
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Re: Mower based MV electrical design question

Postby GreyCoyote » Sat Mar 22, 2014 3:02 pm

Colonel Monk wrote:Battery of the Marine/RV - Starting/Deep-Cycle variety has a capacity of about 85 amp-hours (Ah). This means, it can put out 85 amps of power in one hour before it's dead (it will always be less) or it can produce much more power than that over time at a lower load - say like, 10A-20A.....



Just a quick correction to a great post: depending on the battery type, the AH rating is expressed at either 1/10th of the nameplate rating, or 1/20th. Go either side of that rating curve and things get very different.

Example: if you have a 100 AH battery, it will provide 10 amps for 10 hours (if its rated at the C/10 rate, which is typical). It will NOT produce 100 amps for 1 hour. In a like manner it will produce MORE than 1 amp for 100 hrs. The manufacturers produces curves to let you know how to rate expected performance on either side of the "standard" rating curve. Its important to get those curves and understand how they may impact your runtimes. :mrgreen:
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Re: Mower based MV electrical design question

Postby Elliot » Sat Mar 22, 2014 4:34 pm

The alternator that Captain Goddammit recommends is the General Motors CS-130. According to what I wrote down, these were used in late 1980s to early 1990s GM small cars and the Chevrolet S-10 pickup.

I can add that... the way they are used in cars, they connect with several wires. They must be converted to one-wire. This is done by replacing the (internal) regulator with a marine (boat) regulator, also called a self exiting -- SE -- regulator. This needs to be done by someone with the correct skills, but the regulator is not expensive.

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Re: Mower based MV electrical design question

Postby Shoeshine » Sun Mar 23, 2014 1:11 am

Now Holy Crap!!

That is a damn sight of a post chock full of useful (and even better, actionable, information)

Thank You Cpt. Monk. ( & Grey and Elliot for clarifications)

The reason I am considering the alternator is there is that spot just itching for use i.e. the mower blade pulley. Easily mounted, easily changed to whatever size pulley needed to get needed rpm. There is the issue that until I get this thing built I am not sure at what portion of throttle it will run best. Long story, but I am running a set of sprockets w/ large roller chain to generate very low rpm/high torque. Regardless you are right, I have no lack of oomph to turn an alternator.

But like I said, actionable. I am not an automotive guy but this gives me some insight to look into the problem ...off to look up a bunch of specs and tap furiously at my calculator.

I do appreciate the input about real usage though. It's true that a good chunk of time on playa will probably be spent at rest. After all, cruising is a blast but the best part of TTITD for me is stopping to interact with all you glorious folk. I admit this is pushing me toward the turn-key solution of the small inverter/gen. When noise is not so much of an issue, It seems there are some honda eu1k clones that seem to have decent reviews barring db rating in the $3-500 range (not insignificant but also not huge when considering the cost of the project as a whole). I also like the idea that a dead starter battery can be solved with a can of gas and a brief wait.

Honestly, I might be overthinking this. My electrical draw shouldn't be enormous, I just want to have better capabilities than some EL wire and a pack of D-cells. As you said, headlights, significant glow, and perhaps a stereo.

But anyway... Damn... again... thank you
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Re: Mower based MV electrical design question

Postby Colonel Monk » Sun Mar 23, 2014 5:20 am

GreyCoyote wrote:
Colonel Monk wrote:Battery of the Marine/RV - Starting/Deep-Cycle variety has a capacity of about 85 amp-hours (Ah). This means, it can put out 85 amps of power in one hour before it's dead (it will always be less) or it can produce much more power than that over time at a lower load - say like, 10A-20A.....



Just a quick correction to a great post: depending on the battery type, the AH rating is expressed at either 1/10th of the nameplate rating, or 1/20th. Go either side of that rating curve and things get very different.

Example: if you have a 100 AH battery, it will provide 10 amps for 10 hours (if its rated at the C/10 rate, which is typical). It will NOT produce 100 amps for 1 hour. In a like manner it will produce MORE than 1 amp for 100 hrs. The manufacturers produces curves to let you know how to rate expected performance on either side of the "standard" rating curve. Its important to get those curves and understand how they may impact your runtimes. :mrgreen:


You're right!! For future's sake, I shall go back and edit. It's been a while since I did my research.....

But I stick to my 2 battery rating - it'll make sure that he's got room to grow - my experience is that as we get into it, we will be adding power amps for the stereo, and additional lighting, horns, etc....

Thanks for the fact checking - I need somebody watching my back. :twisted: :coffee:
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Re: Mower based MV electrical design question

Postby Colonel Monk » Sun Mar 23, 2014 5:33 am

Elliot wrote:The alternator that Captain Goddammit recommends is the General Motors CS-130. According to what I wrote down, these were used in late 1980s to early 1990s GM small cars and the Chevrolet S-10 pickup.

I can add that... the way they are used in cars, they connect with several wires. They must be converted to one-wire. This is done by replacing the (internal) regulator with a marine (boat) regulator, also called a self exiting -- SE -- regulator. This needs to be done by someone with the correct skills, but the regulator is not expensive.

:D


Thanks Elliot. I should have mentioned the kits are no big deal. We had the alternator on my old man's 1949 Chris Craft converted to a one wire as well. We used an automotive electric place.

A quick check of google-ville showed 100 amp one-wire alternators available for around $120.

The CS-130, is also a 100 amp alternator, and I found several sources (including ebay) selling remans for $70-100. Those converted to 1 wire are more expensive. I'm sure the pick N pull is your best solution for cheap, but depending on the cost of the conversion might be more economical to buy one already done, or a different alternator? Choices....
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Re: Mower based MV electrical design question

Postby Colonel Monk » Sun Mar 23, 2014 5:49 am

Shoeshine,

Now, again...... having a little honda genny is always nice (because they are awesome) but...

When you are sitting still, you pretty much have tons of battery power to run nightlights FOR HOURS if you're doing LED/EL WIRE. On my rickshaw (which is electric) I ran the entire sound system off and lighting off one battery. It would run all those lights all night long - but not with the stereo running.... And that was a really fun part of it. We used it at our bar sometimes as a sound system, we filled dark streets with music, we filled deep playa with music..... I have been planning to add another battery, or just run consolidate and run the lights and stereo off the main motor batteries (4 x 115Ah 12V)....

If you were to step it up a notch and do 4 batteries, you'd have so much in reserve, that you would not need the generator at all, and you'd still have the option of jumping the motor battery from the battery bank if needed.... But I doubt you'd need more than two - Even if you were parked for 3 hours with stereo ripping, all you have to do is get on the move and engage your alternator and you're in the power biz again.

Yeah, I'm leaning towards your alternator idea. It's not as much of a no-brainer as generator, but like you said, the PTO pulley is screaming for something to do - and if you go battery, you won't need to listen to the genny while you're stopped. Also won't need to do fuel fills into those rinky-dink tanks spilling on playa.

Think about it.

CM

I'd like to hear more of your plans for the MV. Small vehicle, so are you planning to pull/push something?
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Re: Mower based MV electrical design question

Postby Colonel Monk » Sun Mar 23, 2014 5:53 am

Sorry guys, I can't edit the original post anymore. I forgot how fast that dries up around here, but it keeps people thinking honestly when they can't change history!!

Anyway thanks to you all the little mistake was quickly corrected. Rock Onward.
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Re: Mower based MV electrical design question

Postby GreyCoyote » Sun Mar 23, 2014 6:29 am

I want to go back to DaMonk's chart for a second. There is another key takeaway point in that chart that might have been missed.

Battery charging really shouldn't happen faster than the C/10 rate (ie, 1/10th of the nameplate AH rating. If you have a 100 AH rated battery, then your max charge current should be about 10 amps. In a perfect world you would actually charge at about C/20 to prevent outgassing, but nevermind that for now). So lets assume you have two of these 100 AH batteries as Monk suggests. That gives you a suggested charging current of 20 amps.

Now lets look at the alternator chart. Follow the 2000 rpm line upwards and you'll see even the smallest listed alternator at 2000 rpm gets you almost twice what you need. (Output is an even 40 amps). The higher-output alternators do even better at the same speed (about 70 amps). That is a LOT of current available, even at idle speed.

So the takeaway here is you don't need to spin that alternator fast at all to make enough current to both charge your batteries and power your lights/stereo at the same time. At a 2:1 pully ratio you could actually be at engine idle speed (about 1200 rpm on the crank, or 2400 rpm on the alternator) and get enough juice to do it all and then some.

I would consider pulling the fan off the alternator shaft and swap it for one with a very aggressive blade design. An alternator driven hard at low RPMs may tend to overheat, so you want to pull as much air though that thing as possible. Some summer-day testing with a stiff load and an IR thermometer might be a good idea before you take this to the playa. :mrgreen:

Alternatively, you could get a little Honda EU1000 or EU2000 coupled to a 30 amp charger and be done with it. :mrgreen:
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Re: Mower based MV electrical design question

Postby EspressoDude » Sun Mar 23, 2014 7:18 am

thoughts about the alternator fan: they can and do run HOT, but they are designed to sit behind a car radiator idling in traffic with the air conditioner, blower, stereo, and lights on; and have enough capacity to charge the battery. I would leave the alternator fan installed. The fan pulls air through the coils, not just over the alternator like an external fan would
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Re: Mower based MV electrical design question

Postby GreyCoyote » Sun Mar 23, 2014 10:38 am

EspressoDude: I agree completely. What I was suggesting was replace the stock fan with a more aggressive one. In other words, same location and still shaft driven.

The alternators found on older ambulances have exactly this mod. If the OP could find one of these, and just swap it onto the shaft, it would move more air.

The other mod is remote the diodes. This allows for much better cooling, but its a lot of work and futzing for what I suspect to be diminishing returns in this case. :mrgreen:
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Re: Mower based MV electrical design question

Postby Colonel Monk » Sun Mar 23, 2014 3:13 pm

OK, now I could be completely wrong, and I am ALWAYS willing to be wrong and/or proven wrong.

Unlike some people out there, that are always right, even when wrong - I need to learn! So if anything I say is bullshit, let me know.

Most of what I know about charging, I figured out when I was building my electric MV, and like GreyCoyote said, you want to pay attention to the charge rate, and/or use a multi-stage smart charger that will do it for you. For my MV, I've got a 4-stage charger that takes care of all of that.

Regarding alternators, I have for the most part always accepted that they charge when I need them to, and they stop once the battery is charged. We are kind of stepping outside that natural boundary a little though using the alternator outside a car, so maybe a little more research is warranted.

So back to this project - I do hear what GC saying about charge current, but I think perhaps we are mistaking charge rates with alternator output capacity.

If you are charging a battery with a single stage / fixed current, than I agree, you would not want to charge at current beyond C/10 or so, for any length of time. So, 10 amp charger for 100 Ah battery? And even then, you can't just walk away from your average battery charger overnight - once the voltage in the battery reaches full charge, there will be a build up of heat in the battery that is potentially unhealthy for the battery, as well as it will cause some of the electrolyte (battery solution) to outgas or boil over. Not good.

Regular old garage battery chargers do not have the ability to reduce charging voltage, so overcharging WILL HAPPEN if you don't remember to turn it off.

Now, multi-stage chargers, have different charge rates depending on the state of charge of the battery, to prevent this overcharging problem. It's important to remember, that the charging VOLTAGE in a simple charger is what determines current flow - the higher the voltage, the more current flows. So by regulating charge voltage, you regulate the charge current.

The battery will only take the necessary current needed to charge, given a proper voltage regulator. There is a threshold voltage that is required to get current to flow into the battery, thus charging it. The higher the voltage difference between battery and charge source (alternator) the more current that will flow.

So just because you have a 100A alternator doesn't mean that it outputs only 0 or 100 amps. Voltage regulator adjusts the alternators output to suit needs - I double checked this though to be sure:

http://www.powermastermotorsports.com/faq-alternators.html#15 Simple Answer
Will a higher amp alternator hurt my battery or charging system?

No. A good rule of thumb is that more amps are not harmful, but more voltage is. If you look at electrical power like water, amperage is equivalent to the volume of water, and voltage is equivalent to water pressure. More amperage is like having a larger pool of water to draw from.

http://www.autoshop101.com/trainmodules/alternator/alt131.html Better Answer
The regulator will attempt to maintain a pre-determined charging system voltage level.
When charging system voltage falls below this point, the regulator will increase the field current, thus strengthening the magnetic field, which results in an increase of alternator output.
When charging system voltage raises above this point, the regulator will decrease field current , thus weakening the magnetic field, and results in a decrease of alternator output

http://www.4x4earth.com.au/forum/electrical/26768-can-alternator-overcharge-battery.html Best in depth answer
The battery presents a variable load to the alternator; when it is at (say) 12V0 then it's around half capacity and the alternator will put maximum charge into the battery by increasing the system voltage to 14V5 (or whatever).

As the battery gains charge its terminal voltage rises and according to Ohms law, because the differential between alternator voltage and battery voltage is now less, so the current forced into the battery reduces. In addition to this the electronics in the alternator (voltage regulator) will reduce the system voltage according to a predetermined curve so as the battery terminal voltage rises thus the system voltage will reduce. The idea is to charge the battery back to (say) 85% as soon as possible but not to overcharge it.

Once the alternator is satisfied that the battery is near to full charge it will reduce the system voltage to around 13V8 which is the "float charge" voltage for 12V lead acid batteries and the nicest thing you can do to a lead acid battery is to keep it on float charge. Essentially, this process compensates for internal losses in the battery and maintains it at maximum charge thus minimising sulphation. Temperature plays a part in this process too and modern alternators measure underbonnet temperature and adjust their charging curves accordingly.


None of these answers really explains exactly what is happening, but I think any more detail is where the layman's head starts to hurt. But based on what I'm reading, modern voltage regulators are sensing the needs of the battery and are able to regulate both voltage AND current dependent on the voltage differential between the battery and alternator.


For discussion sake only, multi-stages of charging.... This kind of helps to understand why it's necessary to control the voltage and current at different stages, and how this is done in modern multi-stage chargers for RVs, Solar, etc. This is the kind of charger I'm using on my MV to recharge it ASAP without damaging the batts.

http://batterytender.com/resources/battery-basics.htm/#answer7

Bulk Stage: From below 50% capacity to 80% capacity - constant current (high), rising voltage. There is a limit to appropriate current, but you can charge safely at currents greater than mentioned earlier in the discussion. The trick is, that you reduce the current at 80% charged, so that you do not overheat the battery.
Absorb Stage: From 80% capacity to 95% capacity - constant voltage, falling current. The charger applies a constant voltage at a lower charging current, and as the voltage differential between charger and battery decreases (they get closer together) the current is reduced. Again, this is done to avoid excess charging heat.
Equalization Stage: From 95% to 100% (if possible) - constant current (low), rising voltage. - this is like the Bulk stage, but is done at low current to try and get the last 5% charge restored without excess heat.
Float/Maintenance: Generally timered cycles of charge at low current to keep battery fully charged.
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Re: Mower based MV electrical design question

Postby Captain Goddammit » Fri Mar 28, 2014 8:41 pm

I'm gonna come back from the dead for long enough to answer this.
I have done both ideas here, a Honda EU generator aboard a mutant vehicle and added extra alternators with deep-cycle batteries and an inverter.
The alternator/battery/inverter system is hands down superior in every way! You're running an engine anyway, so why not use that power?
A mower with a ready made, ridiculously easy way to drive an alternator (the unused mower drive pulley) makes this an absolute no-brainer.

In my experience, on my mutant vehicle the Honda had issues getting choked up with playa dust. Since converting to alternators off the engine with deep-cycle batteries and a big inverter, I just magically have electricity, all the time.

I can go full-on electrical techno-speak but I'll keep this real-world simple as much as possible.

I use TWO CS-130 alternators. I like them because they make a lot of current at low speeds. They all come with serpentine-belt stye pulleys on them. You'll have to unbolt that and bolt on an old v-belt style pulley from some old alternator because your mower's drive pulley is probably a v-belt type. In actual practice on the playa, I can hold a 1000 watt 120-volt AC load through my inverter with the engine idling. I get them from junkyards for dirt cheap. I highly recommend a pair of alternators; you have the space and the power, why not. Even if you don't use all the power you could, it's a good idea because each one will be carrying a lighter load and will last longer. The playa also teaches you that redundant systems are a good idea. If one fries, you're still in business. I've had it happen.

You don't need to waste your money on any goddamm one-wire conversion. Wiring these things is extremely easy. There are four terminals on the alternators connector plug, you only use two of them - the "S" and the "L" terminals. The "S" terminal just needs to be wired directly to the alternator's Battery terminal.
The "L" needs to be hooked up to 12V power that is hot when the ignition key is ON. The only trick is you need to put a small 12-volt lamp inline with the "L" wire. You can use a small side-marker lamp or whatever from an auto parts store.
Yes, that lamp needs to be there… it originally would have been the "Alternator" warning lamp on the car's dashboard but it also acts as a resistor and prevents frying the regulator. The alternator won't function if that bulb isn't connected. They actually sell little wiring harnesses with the connector plug for a CS-130 and a resistor built in to make it completely "plug-and-play" but really, it's simple.
When I get the alternators out of the cars at the wrecking yard, I cut out the connector plug with it, or you can buy them new. They call it a "pigtail", it'll have the plug and a few inches of wire coming out of it.

So… "S" straight to the alternator's "BATTERY" terminal (the main power output) and "L" to switched 12V power, with a small 12V lamp inline with it. Easy.

Another on-playa in-practice lesson I learned is about inverters. Those shitty ultra-cheap ones are OK for incandescent lamps but they don't function well, if at all, with fluorescent lights and they don't work well with LEDs. You need a "Pure Sine Wave" inverter. NOT a "Modified Sine Wave" like those cheap pieces of shit the auto parts stores sell. The best deal I found was a Xantrex ProWatt SW. They make a ProWatt that isn't an "SW"… the "SW" means "Sine Wave". Don't get the non-"SW". I went with the 2000-watt model, it was about $300-ish from West Marine. They make smaller ones but they aren't that much cheaper.
There are a lot of cheap Chinese pure sine wave inverters on the market and according to al the reviews, they are crap. I have found it's cheaper to buy good stuff the first time.

The cheap inverters will make LEDs flicker annoyingly and only get about half-bright. Fluorescent lamps often won't "start up".

The most overlooked thing about inverters is that they can only put out what you put into them. It takes ten times the AMPS at 12 volts going in to make the same power going out at 120 volts. To put out 1000 watts from your inverter, you have to feed it almost 100 amps, and that requires BIG FAT battery cables, as short as possible. I use 2-gauge, and two of them. And it's not enough.

About lights: I like LEDS and fluorescents on MVs. You can get LED rope light around Christmas at Costco for cheap, or all year at Wally Mart, and fluorescents are cheap and very bright and have pretty low power draw for their output.

If you do the twin-CS130 alternator setup with a deep-cycle battery or two, you'll have plenty of power for all sorts of lighting, even cheap power-hungry incandescents. I just like the lower power draw of LEDs so I can run them longer when the engine is off.
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