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 Anyone know of a HAM HT and/or GMRS HT with a "hand crank" charging option in addition to the normal stuff? With the way things are going these days, might not have any way to charge batteries after all the "Extra" ones are depleted. 

Thanks in advance! :-)>

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9 minutes ago, WRXP381 said:

The midland is about it that I know of. However they do make 12v and 5v usb hand crank chargers.  Also a small solar/battery back up unit is also a good idea. 

I was going to mention the solar as well. The portable solar chargers and generators are way better than they used to be and are plentiful in the marketplace.

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I set up my work truck with solar and an inverter setup.  Not exactly a big power source but it works well.  I have a 105Ah AGM battery that I've been running for about 8 years now and I've swapped over from four 30 watt panels and a 10A SolarEpic controller to two 100 watt BiFacial panels and a 15 amp Victron controller which does so much better.  My original controller had a bug in it that the manufacturer refused to acknowledge even though I sent them a video of it with the active problem.  My battery never really charged fully for years.  It still worked and I had power on my tailgate.  I swapped over to the Victron controller and within a week or so my battery was revived and working much better.  Plus it has a bluetooth management system with a 30 day recording of what is going on with the controller.  So if I have my truck I have a somewhat unlimited source of power withing the confines of my battery and panel output.

This is the original setup with the SolarEpic charge controller and panel.  That was swapped out for the Victron controller.  Black box to the right is a shore power charger in case I go through the battery during the day and have to charge it up overnight for the next days activities.  That doesn't happen very often in the new setup.  If I run the inverter and the sun is beaming well it can keep the battery fully charged with the 2 amp draw from the inverter.  Then the occasional use of a chopsaw or belt sander when needed and usually it works all day.  I've run my house on it several times in the winter keeping the fridge, freezer and oil burner chugging along without incidence.

image.thumb.png.786abfcbafbb7db5f5fd373717e3fb67.png

 

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  • 1 month later...

You are far better off to build something like a stationary bike with a generator / alternator on it than anything that's 'hand crank'.

The amount of power generated vs the amount of physical energy expended on hand crank anything is not worth it, especially in a bad situation.

It comes down to charge rate.  If you can charge a battery with 10 amps for 30 minutes with a stationary bike, a hand crank anything is only going to be half that current or less.  Requiring a longer period of time cranking.  And you are using muscles that aren't as powerful.  My opinion is you need to consider energy conservation. Personal energy conservation.  And a stationary bike needs to really be a tool of last resort.  Solar and wind are going to work without your physical effort. Yes, they are only semi portable, same as the bike.  But it's a solution for a home base of operations for sure. 

My advice is a bike on a stand with a belt on the back rim connected to a generator.  Get a bike with multiple gears to at least figure out to optimal ratio for generating power and not killing yourself doing it. 

Remember that alternators (from a car) will require some amount of voltage to get the field coil going.  So a generator would be better but are harder to find.  But any small amount of voltage is enough to start the field and get you rolling.  Or you can modify the alternator with some magnets to jump start that process. 

People are doing that sort of thing all the time with DIY wind generators.  Might be a good place to start looking at what's needed.  

And if you really want it to be hand crank.  Mount the bike in a way that you can hand crank it and just modify the pedal for hand use.  Or you might try a kids bike with a smaller rear wheel.  Automotive alternators spin at 4 times the crank speed.  So if the engine is turning 2000 RPM the alternator is going 8000 RPM.  Bear that in mind with the design as well.

 

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Something else to stick in here.  Anything  that is going to vary in input RPM will not work well for direct AC generation.  Meaning AC (house current) generators have a pole count.  Two pole generators need to spin at 3600 RPM to generate 60 Hertz power.  Four pole generators need to spin at 1800 RPM to generate 60Hz power.  Varying the RPM on an AC generator will vary the frequency output. 

You are far better off to create DC power and charge a battery bank and if AC power is needed, create that AC power with various sizes of inverters.   The reason for the various sizes of inverters is the idle load of the inverter.  A 5KW inverter will at idle draw as much power as a 100watt inverter at half load.  So just having one big inverter is going to waste power as heat. 

I am kinda going away from portability here.  I know the initial question was about 'hand crank' stuff.  But if you look at what's available that is hand crank powered, it's LED lights and small broadcast radios.  If you start reading the specifications for those items, you will find that 10 minutes of cranking will get you no much more in listening or operating time on the little AM radios.  The LED lights are a bit better, but LED lights are very low loads.  If there was a direct USB crank charger, consider the time it takes to charge a phone or a portable radio with USB charge.  Even at fast charge, that is going to take an hour if the battery is depleted.  So that's an hour of cranking.  Having several solar charged USB power banks to set in the light would be a better option.  They will free you up to do other things in a bad situation. 

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12 hours ago, WRKC935 said:

Automotive alternators spin at 4 times the crank speed.  So if the engine is turning 2000 RPM the alternator is going 8000 RPM.  Bear that in mind with the design as well.

That’s some funny stuff.    This is a bold statement that is not really true in any meaningful way.  An automotive alternator spin speed has to do with the 2 pulleys  that are spinning the alternator.  The spin speed has to do with the relationship of the crank pulley and the alternator pulley.  Companies like monster put on smaller pulleys to spin it faster and make more volts at idle.  Each alternator is different and you would need to know the speed at which each and every alternator puts out 14.1 volts at max amps and make that the target spin speed.   Alternators out of police interceptors, ambulance prep packaged trucks and vans, and tow trucks are several that have higher amp alternators at lower motor rpm’s.  Sometimes it helps to actually know stuff. 

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10 hours ago, WRKC935 said:

Two pole generators need to spin at 3600 RPM to generate 60 Hertz power.  Four pole generators need to spin at 1800 RPM to generate 60Hz power.  Varying the RPM on an AC generator will vary the frequency output. 

The bold sentence is incorrect.
I understand why it might seem like that but each set of poles (North-South) simply adds an additional phase. Added phases cannot be combined to increase the frequency because they are out of phase with each other. A four pole generator will simply generate two separate phases of 60 Hz AC, presumably 90° out of phase. Three phase generators have six “poles”, three north and three south, but each North-South set is 120° from the other two.
Automotive alternators have either 12 or 16 sets of poles. As you correctly pointed out earlier the only practical way to get 60 Hz AC from the output of a car alternator is to rectify it and filter it to establish DC, and then run the DC through an inverter to make AC. 

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1 hour ago, SteveShannon said:

The bold sentence is incorrect.
I understand why it might seem like that but each set of poles (North-South) simply adds an additional phase. Added phases cannot be combined the first one to increase the frequency because they are out of phase with each other. A four pole generator will simply generate two separate phases of 60 Hz AC, presumably 90° out of phase. Three phase generators have six “poles”, three north and three south, but each North-South set is 120° from the other two.
Automotive alternators have either 12 or 16 sets of poles. As you correctly pointed out earlier the only practical way to get 60 Hz AC from the output of a car alternator is to rectify it and filter it to establish DC, and then run the DC through an inverter to make AC. 

In addition to this, the inverter can be built into the generator. Inverter generators produce constant 60Hz despite fluctuating RPMs.  At lower RPMs they produce less amps. (And less noise, and lower fuel consumption.)

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12 hours ago, Socalgmrs said:

That’s some funny stuff.    This is a bold statement that is not really true in any meaningful way.  An automotive alternator spin speed has to do with the 2 pulleys  that are spinning the alternator.  The spin speed has to do with the relationship of the crank pulley and the alternator pulley.  Companies like monster put on smaller pulleys to spin it faster and make more volts at idle.  Each alternator is different and you would need to know the speed at which each and every alternator puts out 14.1 volts at max amps and make that the target spin speed.   Alternators out of police interceptors, ambulance prep packaged trucks and vans, and tow trucks are several that have higher amp alternators at lower motor rpm’s.  Sometimes it helps to actually know stuff. 

FROM DELCO REMY web site.

Alternator Output
All alternators are listed at maximum output. Since alternators are rotational devices, the output listed is at approximately 5,000 RPMs, shaft speed. The alternator pulley is much smaller than the crankshaft pulley, so it is turning much faster than the engine RPM (generally 3.5:1, up to 4:1 ratio). This means that the alternator is well into its maximum output when the vehicle is going 65 mph.

https://www.delcoremy.com/the-latest/2018/january/how-to-select-the-right-alternator

2K RPM time 4= 8K RPM.

You're right.  It does help to know things.  Which it seems I do, at least about this. 

 

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10 hours ago, SteveShannon said:

The bold sentence is incorrect.
I understand why it might seem like that but each set of poles (North-South) simply adds an additional phase. Added phases cannot be combined to increase the frequency because they are out of phase with each other. A four pole generator will simply generate two separate phases of 60 Hz AC, presumably 90° out of phase. Three phase generators have six “poles”, three north and three south, but each North-South set is 120° from the other two.
Automotive alternators have either 12 or 16 sets of poles. As you correctly pointed out earlier the only practical way to get 60 Hz AC from the output of a car alternator is to rectify it and filter it to establish DC, and then run the DC through an inverter to make AC. 

From the Generator source web site.

Changing Engine Speed to Vary Output Frequency

Present-day generators consist of an engine directly connected to an alternator to produce electricity. One of the most common ways of changing the output frequency of a generator is to change the rotation speed of the engine.

The two factors are related as per the following formula – Generator Frequency (f) = Number of revolutions per minute of the engine (N) * Number of magnetic poles (P) / 120 Conversely, P = 120*f/N

As per the above formula, a 2-pole generator producing an output frequency of 60 Hz has an engine speed of 3,600 rpm. To change the output frequency to 50 Hz for the same generator configuration, the engine speed needs to be reduced to 3,000 rpm. Similarly, for a 4-pole generator, an engine speed of 1,800 rpm produces output of 60 Hz. Reducing the engine speed to 1,500 rpm yields an output of 50 Hz.

https://www.generatorsource.com/Generator_Frequency_Conversion.aspx

It was a bold statement.  But it was a 100% CORRECT bold statement. 

It comes up as soon as you Google it for God sake. 

https://www.google.com/search?client=firefox-b-1-e&q=Generator+poles+and+speed

Click down on 2 pole speed, then 4 pole speed and it clearly states what I said. 

Yes, 3 phase generators have more poles.  But most of them are 1800 RPM or lower in operation.  Depends on the size of the generator head and the engine size.  Big engines don't make 1800 RPM.  The mammoth stuff is under 800 RPM.  Mind you a train engine diesel motor maxes out at 1000 RPM.  Talking about stuff bigger than that.

Little pull start gas generators that are 110 only have two poles that are not tapped at the center.  Half the winding is on one pole the other half is on the other.  For a slightly larger 110/220 generator.   Each pole creates 110 volts.  There are 3 slip rings on those stators and the center is tapped and those poles are 180 degree's out of phase.  So when one side is producing a positive going wave, the other one is producing the negative going wave.  Since there is a center tap, each leg can be individually referenced to the center tap and produce 110 volts, and across both legs 220 volts is created since they are 180 degree's out of phase.

 

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Im not sure what people consider "portable" in any given case, but solar and LiFePo4 batteries are light and cheap. 300w hrs of batteries and 100w of solar is about 17 lbs.  650w hrs of battery and 200w of solar panels is about 30lbs. 2,600w hrs of batteries and 600w of solar are under 100 lbs for vehicle portable. 

 

Unless you're planning on building a very heavy, portable hydro or wind station, I would never consider any kind of crank generator. Even at that, the wind and flowing water are no where near as reliable, constant and abundant as the sun.

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3 hours ago, WRKC935 said:

From the Generator source web site.

Changing Engine Speed to Vary Output Frequency

Present-day generators consist of an engine directly connected to an alternator to produce electricity. One of the most common ways of changing the output frequency of a generator is to change the rotation speed of the engine.

The two factors are related as per the following formula – Generator Frequency (f) = Number of revolutions per minute of the engine (N) * Number of magnetic poles (P) / 120 Conversely, P = 120*f/N

As per the above formula, a 2-pole generator producing an output frequency of 60 Hz has an engine speed of 3,600 rpm. To change the output frequency to 50 Hz for the same generator configuration, the engine speed needs to be reduced to 3,000 rpm. Similarly, for a 4-pole generator, an engine speed of 1,800 rpm produces output of 60 Hz. Reducing the engine speed to 1,500 rpm yields an output of 50 Hz.

https://www.generatorsource.com/Generator_Frequency_Conversion.aspx

It was a bold statement.  But it was a 100% CORRECT bold statement. 

It comes up as soon as you Google it for God sake. 

https://www.google.com/search?client=firefox-b-1-e&q=Generator+poles+and+speed

Click down on 2 pole speed, then 4 pole speed and it clearly states what I said. 

Yes, 3 phase generators have more poles.  But most of them are 1800 RPM or lower in operation.  Depends on the size of the generator head and the engine size.  Big engines don't make 1800 RPM.  The mammoth stuff is under 800 RPM.  Mind you a train engine diesel motor maxes out at 1000 RPM.  Talking about stuff bigger than that.

Little pull start gas generators that are 110 only have two poles that are not tapped at the center.  Half the winding is on one pole the other half is on the other.  For a slightly larger 110/220 generator.   Each pole creates 110 volts.  There are 3 slip rings on those stators and the center is tapped and those poles are 180 degree's out of phase.  So when one side is producing a positive going wave, the other one is producing the negative going wave.  Since there is a center tap, each leg can be individually referenced to the center tap and produce 110 volts, and across both legs 220 volts is created since they are 180 degree's out of phase.

 

Look, I didn’t tell you that to start an argument.  I did actual work on the generator syncing and transmission protection systems for generators in four different utility power plants and visited several others.  Every one turned the generators at 3600 rpm when generating.  The prime movers varied from hydroelectric turbines (the Nisqually project in the nineties), to coal fired steam turbines (Colstrip power plant from 2005-2008, largest thermal plant west of the Mississippi at the time), to dual fuel gas/diesel turbines at the David G. Gates plant until I retired in 2015.  
All of these plants spun their generators at exactly 3600 rpm.  They would trip offline if they sped up or slowed down. All were three phase system with the Colstrip 3 and 4 units generating 740 megawatts each.

That’s how utility generation works. Each winding adds a North and South Pole and gets you another phase. 

If you insert a second winding in a generator you get another lobe of generated power that is offset by some number of degrees.  If you add a winding that’s perpendicular to the first winding, you end up with a full AC wave in each winding and each wave is separated from the other by 90°, but you don’t double the frequency of a single AC system, regardless of what your article says. Each winding is its own AC system.

I don’t understand what kind of generator they’re talking about when they say they can add a set of poles to generate AC at 120 Hertz. Four poles would result in two sets of North pulses followed by two South pulses.  Because the poles must be diametrically opposing you can’t arrange the windings to get a north pulse followed by a south pulse followed by another north pulse followed by a final south pulse, and if combined they won’t look like the clean 120 Hertz sinusoidal AC power that electric machines require.  I think they would only be useful for generating DC and then fed to an inverter. 

So, as I said, I just don’t understand how the generators cited in the article you pasted work as described. That’s not to say it’s not possible because there are clever engineers out there, it’s just not the way it could work in any AC generator whose controls I ever worked on. Now in a car alternator they do keep adding poles, but the goal isn’t to generate higher frequency AC.  They’re rectifying the power produced by each pole before combining it for DC. 

 

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4 hours ago, SteveShannon said:

Now in a car alternator they do keep adding poles, but the goal isn’t to generate higher frequency AC.  They’re rectifying the power produced by each pole before combining it for DC. 

Yup. The typical automotive alternator is a 3-phase device. They usually embed a 3-phase full wave rectifier on the frame on the back, 6 diodes. The output is DC with a small AC ripple at 6 times the AC frequency of one phase. The reason 3-phase is used is due to the low AC ripple after rectification. In many applications it can be used directly without filtering.

The attached file goes into the electrical theory behind the above.

Rectifiers.pdf

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11 hours ago, SteveShannon said:

Look, I didn’t tell you that to start an argument.  I did actual work on the generator syncing and transmission protection systems for generators in four different utility power plants and visited several others.  Every one turned the generators at 3600 rpm when generating.  The prime movers varied from hydroelectric turbines (the Nisqually project in the nineties), to coal fired steam turbines (Colstrip power plant from 2005-2008, largest thermal plant west of the Mississippi at the time), to dual fuel gas/diesel turbines at the David G. Gates plant until I retired in 2015.  
All of these plants spun their generators at exactly 3600 rpm.  They would trip offline if they sped up or slowed down. All were three phase system with the Colstrip 3 and 4 units generating 740 megawatts each.

That’s how utility generation works. Each winding adds a North and South Pole and gets you another phase. 

If you insert a second winding in a generator you get another lobe of generated power that is offset by some number of degrees.  If you add a winding that’s perpendicular to the first winding, you end up with a full AC wave in each winding and each wave is separated from the other by 90°, but you don’t double the frequency of a single AC system, regardless of what your article says. Each winding is its own AC system.

I don’t understand what kind of generator they’re talking about when they say they can add a set of poles to generate AC at 120 Hertz. Four poles would result in two sets of North pulses followed by two South pulses.  Because the poles must be diametrically opposing you can’t arrange the windings to get a north pulse followed by a south pulse followed by another north pulse followed by a final south pulse, and if combined they won’t look like the clean 120 Hertz sinusoidal AC power that electric machines require.  I think they would only be useful for generating DC and then fed to an inverter. 

So, as I said, I just don’t understand how the generators cited in the article you pasted work as described. That’s not to say it’s not possible because there are clever engineers out there, it’s just not the way it could work in any AC generator whose controls I ever worked on. Now in a car alternator they do keep adding poles, but the goal isn’t to generate higher frequency AC.  They’re rectifying the power produced by each pole before combining it for DC. 

 

2 pole vs 4 pole on the little ones only have two 'magnets' or fields for the stator.  That's how you get 3600 and 1800 RPM with the poles. 

My guess is, since I don't know on the stuff you were dealing with is if they were multiple parallel sets of 3 phase poles and magnetic fields clocked around the stator.  The little ones of course don't really have much room and the field is the armature.  It has two poles and is spun. With a much larger head, I could see it having them in parallel, but I have never messed with stuff the size you are talking about or ever really looked into it. The biggest stuff I have first hand experience with is the sub 350Kw stuff down to the pull start 5 HP things.  Of course with what you are talking about those heads were smaller than the exciters on the generators you were dealing with. 

But yes, North pole, south pole and it creates opposing phases.  I would assume that since you were generating 3 phase, that it's all paralleled internally to increase current.  But in truth, it's all about rise and decay time of the voltage wave.  Has to be 60 Hz when it's all done.  Phasing is just the timing of the events.  For single phase, the events' are 180 degree's out of phase.  For 3 phase, it's 120 degree's from each of the other two phases.  Still all adds up to 360 degrees.  The timing, depending on a fixed RPM is all going to be decided by the clocking of the poles and the number of fields crossing the poles.  To make "big power" you parallel the fields and poles to increase current.  The voltage of course is controlled by the flux density of the field and the winding count in the stator windings.   But I will agree that trying to make sense of whats' going on with a 5 HP portable generator when your experience is with monsters you worked with would be difficult to make sense of. 

Even looking at the 1 / 3 phase units that are between 10 and 100KW can be daunting.  They are wired like a 12 wire electric motor, and the windings can be connected in different series / parallel configurations to produce anything from 120/240 single phase to 480 3 phase.  I still don't fully understand how that works, only that if you have the connection diagram for the different ways to wire it, that it will indeed do it. 

Again, purely guessing, but I would figure you were generating at 13.2KV or something like that to keep the voltage to a minimum because the issues with the insulation on the windings not being able to take much more than that. 

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