Dc Motor Problem

Anything to do with Propulsion.
eng.hossam
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Joined: Oct 1st, 2013, 3:09 am

Dc Motor Problem

Post by eng.hossam »

I bought some 24Vdc motors from an office printers parts Shop ,but every time i use them(at the pool) my Relays(10A-60A) it burns up :cry: .
Any one i asked him say that's impossible that a DC motor in load(water) consume more than 10A.


can any one help ?

thanks :)
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sthone
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Re: Dc Motor Problem

Post by sthone »

How are you powering the motors (voltage?) and what voltage are the relays rated at?

-Steve :sting:
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ROVER3D
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Location: Wuppertal, Germany

Re: Dc Motor Problem

Post by ROVER3D »

Chlorinated water conduct electricity much better than clear water.
Any one i asked him say that's impossible that a DC motor in load(water) consume more than 10A.
Thats bullshit: I have tested brushless-motors in water with (only) 35mm props take at full speed easy 9A. What propellers are you using?
10A is nothing if you want to have some power. My Brushless-units takes 12-15A ...

I think there will be a lot of current you are loosing because of chlorinated water...

What motors you using?
eng.hossam
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Joined: Oct 1st, 2013, 3:09 am

Re: Dc Motor Problem

Post by eng.hossam »

sthone wrote:How are you powering the motors (voltage?) and what voltage are the relays rated at?

-Steve :sting:
I power the motor with 48 v and the relay works on 12 v
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ROVER3D
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Location: Wuppertal, Germany

Re: Dc Motor Problem

Post by ROVER3D »

You have 24Vdc Motors you powering at 48Vdc? :shock:
eng.hossam
Posts: 30
Joined: Oct 1st, 2013, 3:09 am

Re: Dc Motor Problem

Post by eng.hossam »

ROVER3D wrote:Chlorinated water conduct electricity much better than clear water.
Any one i asked him say that's impossible that a DC motor in load(water) consume more than 10A.
Thats bullshit: I have tested brushless-motors in water with (only) 35mm props take at full speed easy 9A. What propellers are you using?
10A is nothing if you want to have some power. My Brushless-units takes 12-15A ...

I think there will be a lot of current you are loosing because of chlorinated water...

What motors you using?
the power of mine is totally insulated, Dc motor brush' 1000rpm 24 v
eng.hossam
Posts: 30
Joined: Oct 1st, 2013, 3:09 am

Re: Dc Motor Problem

Post by eng.hossam »

ROVER3D wrote:You have 24Vdc Motors you powering at 48Vdc? :shock:
I test it directly to 48 v and it can handle it :D
a_shorething
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Location: New Jersey Shore

Re: Dc Motor Problem

Post by a_shorething »

So you're running 12VDC motors at 4x the rated capacity, underwater and you're burning out relays.

I think a few of your assumptions are incorrect. I'd go back to the beginning and work through the process again, eliminating anything that pushes the equipment past it's rated capacity and try again.
eng.hossam
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Joined: Oct 1st, 2013, 3:09 am

Re: Dc Motor Problem

Post by eng.hossam »

no no the motors are 24v and by trying it can be 48v, the relay's coil are 12 v
CLYON
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Joined: Dec 2nd, 2012, 8:52 am

Re: Dc Motor Problem

Post by CLYON »

Everything needs to match. Only run 24VDC to the motors. Only run 12VDC to the relays. As said before, you are exceeding the capacity of your equipment. If your power is 48VDC, you will have to convert the voltage for the motors and relays.

Chuck
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