9 Volt vs AAs

[Mayhem75[TK]]

Hello all,

 

During my waiting period between ordering the armor kit and receiving the armor kit, I have been reading, collecting and planning.

 

My questions to all is electrical. I planning on installing fans in the bucket but not sure how I should power them.

 

Should I go 9 Volt, of 2 or 3 AA batteries.

 

I am sure this is a basic question but I am chemical not really electrical.

 

Thanks for the help

 

Mike

[snoopy trooper[TK]]

9V one pr fan if you can

[Darth Aloha[Admin]]

One AA battery holds 1.5 volts.

 

One 9v battery holds 9 volts.

 

The difference between 6 AA's = 9 volts and 1 9v battery is how long it takes for the battery to drain.

 

I won't bore you with a discussion of milliamp hours... but 1 9v won't last as long as 6 AA's... but it sure fits better in your helmet I also won't go into the fact that most of those squirrel blower (settle down) fans are actually 12v devices... but that's a topic for another discussion.

 

Aloha,

 

-Eric

[Sparrow]

I have two fans, both with 4 AAA powering each. But I can also remove the battery pack and attach a 9v. The AAA dont generate as much power as the 9v, but it still a nice breeze. But it is also WAY quieter!

[Laspector[TK]]

Which will make your fans run quieter?

[Locitus[Admin]]

Which will make your fans run quieter?

Higher voltage makes the fan spin faster, thus make more noise. You could wire up a variable resistor to control voltage, and thus speed and noise if you want.

[Laspector[TK]]

I don't know much about that kind of stuff--so is it AA or 9volt that will make them quieter?

[Sparrow]

I use 4 AAA batteries for each of my fan, and it runs very quite in comparison to a noisier 9volt. AAA is the way to go

[Locitus[Admin]]

I don't know much about that kind of stuff--so is it AA or 9volt that will make them quieter?

4 AA (or AAA for that matter) is 4x1.5 volt = 12 v

[bobojuice]

4 AA (or AAA for that matter) is 4x1.5 volt = 12 v

 

I think your maths is borked.

 

4x1.5= 6v (in a series)

 

I used to use 8AA hooked up in a series (4x4) to power my 12v fans, but I found that the increase in weight was just ridiculous. I have since switched to 2x9v batteries which still gives me over 12v, but reduces the amount of weight. AFAIK, undervolting a fan will cause the battery to drain faster.

[Locitus[Admin]]

I think your maths is borked.

 

4x1.5= 6v (in a series)

 

I used to use 8AA hooked up in a series (4x4) to power my 12v fans, but I found that the increase in weight was just ridiculous. I have since switched to 2x9v batteries which still gives me over 12v, but reduces the amount of weight. AFAIK, undervolting a fan will cause the battery to drain faster.

D'oh!

Of course it is. I wasn't thinking.

[TKRalf[TK]]

I've been actually experimenting a bit with a two fan system with both AA and 9v. I usually have the AA running when I begin. The fan isn't as strong but it will last longer, but once it either begins to slow down or say the heat becomes a bit too much (or I'm in a situation where there is little to no AC), then I turn on the other fan with the 9v for a quick blast of air. Then if the situation improves I can turn off the 9v fan and keep the other one going.

[Darth Aloha[Admin]]

I've been actually experimenting a bit with a two fan system with both AA and 9v. I usually have the AA running when I begin. The fan isn't as strong but it will last longer, but once it either begins to slow down or say the heat becomes a bit too much (or I'm in a situation where there is little to no AC), then I turn on the other fan with the 9v for a quick blast of air. Then if the situation improves I can turn off the 9v fan and keep the other one going.

 

How many AAs are you using?

 

-Eric

[TKRalf[TK]]

How many AAs are you using?

 

-Eric

 

Whoa snap I forgot to respond. My bad. I'm using 4 lithium ion duracell batteries for one fan.

[bigironvault]

I like my 9V the speed makes it feel like air conditioning in there. Haha. It doesn't seem to interfere with my VOX but I can't really hear out that well.

[skyone]

for my arduino project i discarded the AA batteries, they are too big and affected of memory effect, while the 9v is too low amperage

 

the L123A lithium batteries from china could be an alternative but again their amperage is not true and most of them are no brand with bad stories (explosions).

 

i ended to use a Phottix LP-E8 7,4 volts 1400mAh lithium battery. That battery is for Canon 550d/600/650D cameras and i used with my reflex without problems. They last even more ther original canon.

[craig225[TK]]

Anybody else using a 5v fan and 3 AA batteries?

[Dizzydevil105]

does it matter if the batteries are rechargeable or not just curious I read something awhile back about rechargeable being dangerous things might be different these days???

[Darth Hilarious]

There are different types of rechargeable batteries, which act differently.

 

The older NiCad were somewhat temperamental, you had to run them completely flat before charging and charge completely each time to avoid them developing a 'memory'.

More modern NiMH do not develop 'memory', and can be recharged any time and amount.

Lithium vary massively, and I've not found a hard/fast rule for them.

 

Even non-rechargeables exhibit different behaviours.

Differing battery types deliver power differently, some will 'fade out' in voltage as they die, others (notably Ti batteries) will deliver constant voltage until no current remains.

 

I don't use helmet fans myself, so I don't know how pronounced these effects are for them, but they ar sure noticeable in guitar pedals...

 

The only time I've known of rechargeables being dangerous is if you leave them in the charger once full- they tend to get a little 'splodey.

[Nicky]

9V is quicker to install on the field than several 1.5V, I'm the kind of guy who always gets the polarity wrong

 

Personally I'm a fan of non-rechargeable generic 9V, I don't buy the cheapest there is, but if you test some of the cheapest you'll find one that work just as well as the Varta, Duracell, Philips, etc. I didn't meter the output, but all I know is how they all show lower effect after 6 hours when I usually replace. I save my pricey rechargeable batteries and their limited life span to more hungry devices like guitar pedals, walkies or VHF. I'd rather pay for "unpack, use, throw away" than add "put 9V on charger for x hours" in my trooping preparation routines, get lower performances and then choke to death

 

For those wanting a quieter cooling: We could keep the 9V and use wider diameter fans with lower RPM to get more air flow for a quieter spin. I don't know how's the difference in battery drain but *coughdetonatorstoragecough*. Also the best way to lower the noise level is not to put the fan in direct or semidirect contact with the bucket, leave it hanging in the "tube cravace" on a strap if you can, there are pics somewhere (Using a non sticky velcro strap from a pad to under the edge cover http://s19.postimage...s3/IMAG0764.jpg ). So I'd keep it high power.

Edited September 4, 2012 by Nicky

[Dizzydevil105]

There are different types of rechargeable batteries, which act differently.

 

The older NiCad were somewhat temperamental, you had to run them completely flat before charging and charge completely each time to avoid them developing a 'memory'.

More modern NiMH do not develop 'memory', and can be recharged any time and amount.

Lithium vary massively, and I've not found a hard/fast rule for them.

 

Even non-rechargeables exhibit different behaviours.

Differing battery types deliver power differently, some will 'fade out' in voltage as they die, others (notably Ti batteries) will deliver constant voltage until no current remains.

 

I don't use helmet fans myself, so I don't know how pronounced these effects are for them, but they ar sure noticeable in guitar pedals...

 

The only time I've known of rechargeables being dangerous is if you leave them in the charger once full- they tend to get a little 'splodey.

thanks for breaking that down for me

[Nicky]

I don't like creating new threads. So I have a question, I use lots of 9V batteries, they last hours but one event tops, and sometimes I turn the fan off when people don't talk loud enough to me for example to gain some silence.

 

So I thought I could lower the voltage to 5V or so and I forgot my electronics class and want to know if that will help increase battery drain time

 

THIS.

------------

 

A Zalman fanmate 5-11V. I ditch the tachometer wire and just put the 9V battery one end and the fan on the other end. The lack of parts stores in my lazy neighborhood prevents me from DIY-ing.

Edited March 28, 2022 by gmrhodes13
link removed no longer working

[Evilboy[501st]]

I power two squirrel fans with 4AA batteries, and have had very good results. I have had multiple troops from a single set of batteries, and i am now using rechargeable batteries. They are powerful enough to cool me down, and quiet enough for me to hear ok.

[Nicky]

So 6V and two fans via that 4AA series configuration lasts longer, and that makes sense...are these the "imperial fans", squirrel fans?

Edited November 9, 2012 by Nicky

[Nicky]

OK I modded the imperial fans and I must agree with a lot of people. 4xAA (6V) is better than one 9V block battery. Higher capacity, quieter, and about the same chilling effect.