# Voltage Regulator



## Kenneth Milner (Jan 30, 2008)

I feel certain this request for information has been posted before, but thus far I've not uncovered a particular post. 

I would like to know what is a reliable voltage regulator for battery operation. For example, I have two battery packs that each put out 9.8 volts. I would like to connect them together, yet have the voltage output to my locomotives maintained at 12 volts for motors, lighting, decoders, etc. 

Any and all help will be appreciated. Thanks . . . . 

Ken


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## Bill Swindell (Jan 2, 2008)

For 12V output, you can use a 7812 regulator.


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## Kenneth Milner (Jan 30, 2008)

Bill, 

Can you add a few more specifics, like who makes this regulator and where one can be found? 

Ken


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## TonyWalsham (Jan 2, 2008)

There will be a fair amount of energy wasted in the form of heat lowering the voltage down to 12 volts from 19.2. Especially if there is a also a reasonable load on the regulated voltage. 

It would be much wiser to use 12 volt batteries.


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## Kenneth Milner (Jan 30, 2008)

Hi Tony, 

You point is certainly well taken. However I have these two somewhat pricey 9.6 Volt Packs, that are very good, and I would certainly like to put them to good use. 

Do you suppose I could get a couple of 2.4 Volt packs, or there abouts, and make 12 volt combinations? That should accomplish my goals if it will work. 

Ken


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## Del Tapparo (Jan 4, 2008)

10 cells of NiMH or NiCad battteries will get your 12 volts. 10 cell packs can be purchased easily. Before you purchase a battery pack you need to know your load requirements. I assume this is a battery powered loco? (the term decoder is normally used with DCC). How much current does your loco draw? What kind of loco is it?


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## TonyWalsham (Jan 2, 2008)

Hi Ken. 
As long as the batteries have the same chemistry, are the same capacity and size then simply add 2 more cells in series to get to 12 volts (nominal). 
Del is correct. We need a bit more information before we can give you proper advice.


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## Kenneth Milner (Jan 30, 2008)

Ron and Del - Guys, if this double up forgive me. I think I pushed the wrong key a bit ago. 

The battery pack consists of 8 x AA2100mAh batteries that are 1.2 Volt NiMH. So two more cell should bring up to the 12 volts that I desire. 

What I will be installing the packs in are a Precision Scale 1:24 K-27 model and two Sunset 1:24 C-16 models - if I can find one more of the last one. 

The model will have 12 Volt Faulhaber motors - AirWire900 Decoders - Phoenix Sound - a Lenz Gold decoder to control light features with will have 12 Volt bulbs. Not sure what the total amperage draw will be, so perhaps I should calculate that figure. 

Del - I have received a lot of questioning comments when I say decoder. The AirWire remote control unit is called an AirWire900 10AMP Decoder - Model AWD10SS. It can be used for battery power or DCC. 

Thank you both for your input. It is appreciated. 

Ken


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## TonyWalsham (Jan 2, 2008)

Hi Ken. 

I think you should check the compatibility of the AirWire decoder with Faulhaber Motors. 

Faulhaber have stated that it is safe to use a pwm output with their (so called) coreless motors when the frequency is above 5 Hz. 

Below that coreless Faulhaber motors will overheat and may suffer winding damage.


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## Del Tapparo (Jan 4, 2008)

If you are comfortable with adding cells via wiring and or soldering, then that will work. I am guessing 2100mah isn't going to produce very long run times for you (2-3 hours). I would go for 4000 mah if space is available. I'm not familiar with either of those locos or the motos, so just a guess on my part.


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## Kenneth Milner (Jan 30, 2008)

Ron - I will definately check this out. 

I was thinking Faulhaber had a seperate listing in their book for what is termed the "coreless" motor, but when I just checked the book, I was mistaken. There is a seperate listing for "brushless" motors. Mine came from the micromotor list. 

I know the AirWire causes the stock Pittman motor to hum quite annoyingly. Which, according to CVP Al is normal, and a problem they are trying to eliminate with the next generation. 

Thanks for the headsup and I will check things out. 

Ken


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## Kenneth Milner (Jan 30, 2008)

Del - It should be no problem with the wiring and soldering. I've done that before. 

As for the run time, my layout is a really small indoor one. My main interest is in scratch building models and the electronics, though I do want to run them some from time to time. So a 2 to 3 hour run times are not an issue for me. 

I do thank you for the carification on the mAh factor though. That does help with future references. 

Ken


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## Road Foreman (Jan 2, 2008)

Ken, 

The AirWire receivers run on 12 to 18 volts unless they are the leatest 1's that can run on 24 volts.. If you try to run the receivers @ 12 volts, when the batteries drop below 12 volts the receivers may quit.. I would look for some 7.4 battery packs that have the same current rating & put them in series with the 9.6 volt packs.. This will give you 17 volts which is well in the range of the receivers.. Hope this helps.. 

BulletBob


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## TonyWalsham (Jan 2, 2008)

OK. Coreless motors are also known as brushless motors. Check out what Faulhaber say about pwm frequency.


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## Kenneth Milner (Jan 30, 2008)

Tony - I've often wondered if the "brushless" motors and "coreless" motors were one in the same. Thanks for that bit of informaiton. 

The Faulhaber motor I have is listed in the micromotor section and not the coreless section. Not sure if that makes a difference or not where the pwm frequency is concerned. 

I think I mentioned that the stock Pittman motor hummed terrible when connected to the battery power. Al at CVP said it was the pwm frequency. The Faulhaber does not hum at all. 

I added some great knowledge to my storehouse of information from all the replies. I thank everyone. 

Ken


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## TonyWalsham (Jan 2, 2008)

Posted By Kenneth Milner on 08/25/2008 9:00 PM
Tony - I've often wondered if the "brushless" motors and "coreless" motors were one in the same. Thanks for that bit of informaiton. 
The Faulhaber motor I have is listed in the micromotor section and not the coreless section. Not sure if that makes a difference or not where the pwm frequency is concerned. 
Ken



I can't guarantee coreless and brushless are the same. But I understand they are until I am told differently. 
Posted By Kenneth Milner on 08/25/2008 9:00 PM
I think I mentioned that the stock Pittman motor hummed terrible when connected to the battery power. Al at CVP said it was the pwm frequency. The Faulhaber does not hum at all. 
Ken




That is because the Faulhaber doesn't have an armature that can vibrate with the pwm frequency. 

So if you're happy, I am happey.


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## Kenneth Milner (Jan 30, 2008)

To Tony - Bob - Et Al, 

Afte reading the information on this and some other forums, I made some major decisions and changes in my repowering. I think it in my best interest to move to a 24 volt Faulhaber motor. 

The AirWire900 Decoders I have will operate on 24 volts if the J1 Jumper is removed. 

That being said, and done, I still need some sort of voltage regulater for voltage coming from the decoder to a couple of lighting features (I think) and I for certain, need a regulator to drop the voltage to 12 in order to supply power to the Phoenix Sound board and a Lenz Decoder for additional lighting features which will use 12 volt bulbs. 

I have read some tutorials that indicate a voltage drop and be arranged simply by using resistors. Has anyone tried this and if so, how does it work in practice. 

You guys have been great to offer your advice and information. It is appreciated. 

Ken


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## Dan Pierce (Jan 2, 2008)

If running 19.2 volts, just wire the 12 volt bulbs in series. no regulator or power losses/heat generation. 

Or if not bright enough, use 4 bulbs rated at 5 volts in series.


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## Kenneth Milner (Jan 30, 2008)

Tony or anyone who cares to add to my knowledge. . . . 

CVP's suggestion was that I not use the AirWire with any micromotor or coreless motor. 

Does that mean the AirWire900 decoder does not have a PMW frequency greater the 5Khz? Where would one find out what the PMW of the decoder is? 

I am going to get a Faulhaber micromotor to "experiment" with, to see if any problems develop. I guess time will tell. I am hoping, in time, CVP will find the solution to this problem and offer an upgraded chip for these decoders. 

Ken


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## Del Tapparo (Jan 4, 2008)

Posted By Kenneth Milner on 08/27/2008 7:41 PM
... Where would one find out what the PMW of the decoder is? ... 
Ken


Well Ken, that is what I have always found interesting about this hobby ... the lack of specifications. (Although I have to say, the Airwire manuals are top notch).


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## Greg Elmassian (Jan 3, 2008)

The Airwire PWM freq is pretty low, many people report buzzing noise from motor. Not well liked by coreles motors. 

By the way, unless I missed it in someone's post, using a 7812 1 amp regulator to run motors ... ahh... well... will melt down... unless your motors and lights are under one amp, which they aren't ... you have to forget the series regulator idea, unless it's just for a few lights... you need a heat sink and a fan to get an amp from the 7812 inside a closed loco... 

Regards, Greg


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## Kenneth Milner (Jan 30, 2008)

Hi Greg - So far, no buzzing noise from the motor when batter powered through the AirWire. This if with some basic "test stand" stuff though. I am hoping it will continue that way. 

Thanks for the heads up on regulator. With a change in plans as to motor selection, I don't think I will need the regulator. But regardless, it's always good to learn something new. Thanks so much . . . . Ken


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## ConrailRay (Jan 2, 2008)

Brushless and coreless motors are different. 

A coreless motor has brushes and its armature only consists of a specific pattern of windings with no iron core (hence coreless). This makes the motor extremely efficient and allows them to make them extremely small (most pager motors and smaller) Cooling becomes an issue as there's less iron in the motor. They also have absolutely no cogging, which is neat (cogging is basically the magnetic resistance when no powere is applied). 

Brushless motors are kinda the reverse of a standard motor where the elctromagnets are on the outside and the permanant magnet is on the inside on the armature, thus you dont need brushes to contact the inner windings of the electromagnet. Since there are several electromagnets on the outside, they need to be fired in an exact sequence to get the armature to spin, so theres usually more then 2 simple wires and are connected to a specifc microcontroller to coordinate it (most even have feed back for the timing). 

The coreless motors are really neat since they have no cogging. I have a 1/32nd scale GP9 Wada Works live diesel-electric loco and each axle is powered directly by a 12 volt faulhabor coreless motor geared 1 to 8 directly to the axle, so the loco rolls totally freely if its not powered or you go into neutral like a real loco. 

-Ray


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## steam5 (Jun 22, 2008)

A coreless motor is not a brushless motor.

A coreless motor has no armature core and a brushless motor does not have a brush and commutator arrangement.

An incompatible PWM motor control will over heat a coreless motor causing damage, this is due to not having a core to dissipate heat to.

Hope this helps to clear a few things up.


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## steam5 (Jun 22, 2008)

Ray, you and I must have been typing at the same time!


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