Model Boat Mayhem - Forum

Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: missyd on August 19, 2016, 04:34:42 PM

Title: Voltage reduction module
Post by: missyd on August 19, 2016, 04:34:42 PM
I am looking for a way to reduce 12V to any lower voltage ... is there a ready to use module available on the market?
I'd like to use it in my boat models. Sometimes 12V is too much and the motors are turning too fast at full speed. Would be nice to reduce the voltage to 10 or 8 volts ...
Title: Re: Voltage reduction module
Post by: boatmadman on August 19, 2016, 04:57:18 PM
Hi,
Voltage can be reduced by using a transformer, but, in all reality, the easiest way would be to just use a lower voltage battery.


Alternatively, just exercise a bit of thumb control and keep the speed down.  :-))


Ian
Title: Re: Voltage reduction module
Post by: destroyer42 on August 19, 2016, 05:01:21 PM
Hi Missyd,
Component shop have what you want www.componentshop.co.uk

Destroyer42
Title: Re: Voltage reduction module
Post by: john44 on August 19, 2016, 06:50:07 PM
If you are referring to the mini voltage reducer I don't think that would do I think it is designed
more for reducing speed to radar motors etc.


John
Title: Re: Voltage reduction module
Post by: barriew on August 19, 2016, 07:10:32 PM
If you are referring to the mini voltage reducer I don,t think that would do I think is is designed
More for reducing speed to radar motors etc.
John


..... and you can't use a transformer with DC  %% %%


Barrie
Title: Re: Voltage reduction module
Post by: Chris57 on August 19, 2016, 09:01:26 PM
Hi, I am not a black artist, but ........if you search e-bay for "variable voltage regulator board" there are examples of ( cheap) units which look like they will do what you want.


Chris
Title: Re: Voltage reduction module
Post by: malcolmfrary on August 19, 2016, 09:11:37 PM
There are lots of UBECs around that deliver fairly high currents at a set voltage (usually 5) without creating a lot of waste heat, but these are usually intended to power the radio and servos rather than the entire boat.  A lot depends on how much current you need from the regulator.
The cheapest way is to learn to not use permanent full throttle.  Next best is to use either a battery with a voltage that works the model the way you want, or to get the right motor for 12 volts if you are stuck with 12 volts.
Title: Re: Voltage reduction module
Post by: Peter Fitness on August 20, 2016, 02:38:23 AM
I tend to agree that the throttle stick is the best method of speed reduction.


Peter.
Title: Re: Voltage reduction module
Post by: nivapilot on August 20, 2016, 08:25:59 AM
BangGood do a few, always had good service and very quick delivery from them.
Title: Re: Voltage reduction module
Post by: Netleyned on August 20, 2016, 08:48:13 AM
I agree with Malcolm.
Most voltage reducers mentioned on here
would not take kindly to weed on the prop,
plasticbags or duckfeathers with the resultant
hike in current, these things happen almost
daily in a lot of lakes and are unseen until the
model comes to a stop.

Having said that I doubt the Swiss would allow such nasties in their
pristine lakes ;D

Ned
Title: Re: Voltage reduction module
Post by: missyd on August 21, 2016, 04:19:41 AM
Thanks lot lot for all the useful information.  :-))
I will do some tests with the boat first and then decide what solution will be the right one ...
Title: Re: Voltage reduction module
Post by: hama on August 21, 2016, 09:35:26 AM
...or you can use a programmable radio, easy to alter the range/end points of all your channels. Then you have the benefit of being able to increase speed/power from ashore if needed.
Hama
Title: Re: Voltage reduction module
Post by: missyd on August 27, 2016, 04:38:24 AM
As the model is for a customer and the budget limited I had to buy the cheapest RC equipment possible ....
Title: Re: Voltage reduction module
Post by: malcolmfrary on August 27, 2016, 07:32:02 AM
As the model is for a customer and the budget limited I had to buy the cheapest RC equipment possible ....
In that case, if the battery is already decided on, the proper combination of motor and prop is the cheapest and possibly easiest way to go.  What sort of boat and performance is wanted?
Title: Re: Voltage reduction module
Post by: grendel on August 27, 2016, 07:35:47 AM
MFA Como do a speed controller with a potentiometer on the top, this could be introduced to reduce the input voltage, - but would it then interfere with the operation of the actual speed controller, failing that there are voltage droppers, but remember they will have to be rated for the current you will be drawing.
Title: Re: Voltage reduction module
Post by: dpbarry on August 27, 2016, 11:42:46 AM
I am looking for a way to reduce 12V to any lower voltage ... is there a ready to use module available on the market?
I'd like to use it in my boat models. Sometimes 12V is too much and the motors are turning too fast at full speed. Would be nice to reduce the voltage to 10 or 8 volts ...


What sort of voltages are you looking to use? What's you input voltage?


Declan
Title: Re: Voltage reduction module
Post by: missyd on September 12, 2016, 07:47:12 PM
Input voltage would be 12V. From a lead battery.
Title: Re: Voltage reduction module
Post by: NFMike on September 12, 2016, 11:54:39 PM
One cheap way to drop the voltage from the battery is to fit some high current silicon diodes in the line. As a rule they drop about 0.7V each (more or less independent of the current flow unlike resistors), so 3 in series will drop a couple of volts. (But check the spec sheets.)
Buy a pack and some choc-block and just add or take away to get the right result.

They will get warm though, so you may need to make sure they have clear air around them or ventilation.
Title: Re: Voltage reduction module
Post by: missyd on September 15, 2016, 08:16:21 AM
Ok thank you very much for the information. :-))
Title: Re: Voltage reduction module
Post by: IKB on September 15, 2016, 09:02:02 AM
Hi,

We use these modules at work and I use them in my boats, we like them because of the low price and inbuilt display which will tell you input and output voltages.

Ebay:182071344571

Alex
Title: Re: Voltage reduction module
Post by: boatmadman on September 15, 2016, 10:33:42 PM
Alex, those modules look interesting.
Can you tell us please what boats you have them in, and, what input..output voltages you have set.
The motors you run would also be of interest.
Thanks
Ian
Title: Re: Voltage reduction module
Post by: IKB on September 15, 2016, 11:03:38 PM
Hi Ian,

I use them whever I need a supply for an auxiliary feature that is less than main battery, some of the pumps, fans and lights I use require different voltages to the 12 and 5v bec normally available in my models.

Alex
Title: Re: Voltage reduction module
Post by: missyd on October 15, 2016, 05:52:55 PM
Ebay Number isn't valid ...

Found these two modules ...

http://www.ebay.co.uk/itm/5A-75W-DC-DC-Adjust-Buck-Step-down-Converter-Power-Supply-Module-w-Voltmeter-/400935896503?hash=item5d59a445b7:g:OsoAAOSwBahVeTzf (http://www.ebay.co.uk/itm/5A-75W-DC-DC-Adjust-Buck-Step-down-Converter-Power-Supply-Module-w-Voltmeter-/400935896503?hash=item5d59a445b7:g:OsoAAOSwBahVeTzf)

http://www.ebay.co.uk/itm/DC-DC-Adjustable-Step-down-Power-Supply-Module-Voltage-Current-LCD-Display-Shell-/141751990352?hash=item210113b850:g:7AAAAOSwoBtW2YYw#shpCntId (http://www.ebay.co.uk/itm/DC-DC-Adjustable-Step-down-Power-Supply-Module-Voltage-Current-LCD-Display-Shell-/141751990352?hash=item210113b850:g:7AAAAOSwoBtW2YYw#shpCntId)

I would go for the first one as it has 5Amps ....
Title: Re: Voltage reduction module
Post by: IKB on October 15, 2016, 05:58:19 PM
Hi Danielle,


Yes, the first eBay link you have listed is the same unit that I use, very handy little devices.


Alex