DC > DC converter problems please help!!

[BobK]

Here is how I would proceed:

First, get a new DC-DC converter board, the one you have is most likely damaged.

Use a 12V bench supply that can supply plenty of current and measure the current drawn by the motor at 12V. Is this withing the range of output currents your DC-DC converter can handle? If not, then you need a different one.

Assuming the current draw was good, connect a 12V light bulb that draws about 1A to the output of the board, set the output voltage all the way down. Connect your 4.8V battery. Measure the voltage across the bulb and adjust the converter until it measures 12V.

Now connect up your motor, it should run correctly.

Bob

 

[Moha99]

Here is how I would proceed:

First, get a new DC-DC converter board, the one you have is most likely damaged.

Use a 12V bench supply that can supply plenty of current and measure the current drawn by the motor at 12V. Is this withing the range of output currents your DC-DC converter can handle? If not, then you need a different one.

Assuming the current draw was good, connect a 12V light bulb that draws about 1A to the output of the board, set the output voltage all the way down. Connect your 4.8V battery. Measure the voltage across the bulb and adjust the converter until it measures 12V.

Now connect up your motor, it should run correctly.

Bob

Thankfully I do have a few more converters as backup.

Do I have to use a bench supply? Are there any alternatives?

 

[BobK]

A battery made from 8 D cells would be sufficient.

Bob

 

[Moha99]

A battery made from 8 D cells would be sufficient.

Bob

I found some RC batteries would that be good enough? There are a verity for them here:

http://www.hobbypartz.com/batteries.html


So my DCELL batteries that I already have are not good enough? the 2500 Re-chargeable DCELL batteries here is the data sheet for them:

http://data.energizer.com/PDFs/NH50-2500.pdf

 

[Moha99]

or maybe these: http://www.hobbypartz.com/98p-25c-2600-3s1p.html

would that be good enough?

 

[BobK]

Normal Alkaline batteries that you buy at the drug store will have at least 12000mAH and be much cheaper. This is only to test what the motor draws at 12V. You don't need anything special.

Bob

 

[Moha99]

Normal Alkaline batteries that you buy at the drug store will have at least 12000mAH and be much cheaper. This is only to test what the motor draws at 12V. You don't need anything special.

Bob

The thing is I kinda spent most of this months budget for my work so I will only buy something that is completely necessary.
Is it possibile to use a durcell 9V battery? I have two of those is brand new and the other used for while.

the new one is rated at: 8.67V/DC and 0.89 Amps.
the used on is rated at: 6.00V/DC and 0.20 Amps.

Is it possible to use those?
*NOTE: I noticed that when I was testing the new battery and added the + to my + of the ammeter and - to the - of the ammeter the battery kinda heated up I do not know why.

 

[(*steve*)]

Moha, you insist on placing you ammeter across batteries.

STOP IT

NO those little 9V batteries WILL NOT WORK.

Given that you're stretched for resources, I suggest you start with the 4 D cells and the motor.

You know that the motor should operate at 5.1V

connect one lead from the -ve end of the battery to the motor. Then connect your ammeter between the other end of the motor and the +ve terminal of your battery.

Tell us:

1) does the motor turn?

2) what current does it draw?

If at any point you see a current over 2A for more than an instant, disconnect the battery. Either you've done something wrong, your motor demands a huge current, or your motor is shorted (or possibly stalled)

From here we can take one step at a time to getting this working.

 

[(*steve*)]

*NOTE: I noticed that when I was testing the new battery and added the + to my + of the ammeter and - to the - of the ammeter the battery kinda heated up I do not know why.

It's because you are placing a dead short across the battery.

The battery is grossly overloaded and heats up. Some battery types (particularly some rechargeable ones) can catch fire, explode, or leak poisonous and/or corrosive chemicals.

This is why I've told you time and time again, NOT to do it.

Really Moha, the last thing I want to hear from you is:

Hi there, I'm typing this slowly because I just got chemical burns in my eyes and I'm currently blind. The doctor says I may get some sight back in one of my eyes

 

[jackorocko]

Hi there, I'm typing this slowly because I just got chemical burns in my eyes and I'm currently blind. The doctor says I may get some sight back in one of my eyes

but it certainly wouldn't be funny if happened so listen to steve

 

[Moha99]

Well after I wrote my final post I also wrote something else but it did not apear.

I solved my problem the converter worked fine and the motor worked too!

Thank you all for all that support and sorry for the countless foolishness that I've appointed.

But good news is! After an hour of the"LAST CHANCE" moment it finally worked.

Thanks all!

I'll keep experimenting on my converter and hopefully I'll be done with my work

 

[(*steve*)]

Congratulations Moha. Care to tell us what the solution was?

The more mistakes you make, the faster you learn. The important thing is to recognise the mistakes and to know not to repeat them

Don't worry about how silly your mistake may sound, we've all made them (I think there's a thread listing some of them). If your experience helps someone else then that's even better.

 

[Moha99]

Congratulations Moha. Care to tell us what the solution was?

The more mistakes you make, the faster you learn. The important thing is to recognise the mistakes and to know not to repeat them

Don't worry about how silly your mistake may sound, we've all made them (I think there's a thread listing some of them). If your experience helps someone else then that's even better.

Well I just used a brand new 9V durcell battery that I've found setting there just waiting for me to tamper it out!

I connected it to the converter and set the converter's output to about 10V without connecting the motor. Then connected the motor and it worked! and I started to play around with the output voltage while the motor was connected aaaaah that beautiful sound of success! It worked perfectly without any problems at all!

All my mistakes gives me hope nowadays... That I'm going on the right track but I just need to understand it all. After all that effort makes you feel so GOOD!

Now I'll definitely will buy 10x 2500 AA batteries and connected them and play some more!

I finally started to get a hang of electricity and its quite stunning!

I will definatlly help out other people if I can it kinda makes me feel like im an expert but I GOT A LOOOOONG way ahead to reach that hahahaha!

I thank you all again for all the help and I'll keep you updated of my 1.2 AA battery experiment!

 

[Moha99]

I was thinking since the current is high in the input And I will increase the voltage from 4.8 to 13V/DC the current will drop significantly how about that?

Yea it will drop thats what Steve and the other recently taught me