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Can anybody help me with my motor controller? Answered

I need to control a 12V motor using relays and found this circuit using two dpdt relays the most suitable for me,


The motor sucks in 25-30 amps and the current can peak to a max of 50 amps .
Will this arrangement suffice for my motor and if not what to do?
Can relays rated 50 A at 12V used for my motor?

PS: I am a beginner in electronics

http://www.homebuiltrovs.com/howtos/controloptions/relay_hookup.gif

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0
iceng
iceng

Best Answer 8 years ago

Steve is correct !

I don't see the need for your question ?
You have it  Right, and this becomes just a confirmation !

Unless you try to reverse that motor at full speed,
then you can expect almost 100 amps...

A relay can carry more current then it can switch.
Switching capacity is determined by the contacts of the relay.
The more massive and conductive ( Silver not Copper ) the "buttons " are
the more current a relay can switch.

When a contact Closes it bounces and draws miniature plasmic arcs
that pitt the metal button causing future hot and poor connections
which arc more and progressively worsen the overall switching action.

BTW when a switch opens a heavy DC current,
there is an Arc that also causes button pitting.
One day an abused contact will arc enough to weld closed and
then your switch is shot.....

Switch manufacturers use red Vaseline ac a lubricant and
arc extinguishing agent to prolong enclosed switch life span...

A


0
ballom
ballom

8 years ago

Thanks a lot steve and iceng !!!!!!!

0
steveastrouk
steveastrouk

8 years ago

Yes. They must be able to handle the peak current, so 50A is correct.