DIY Electric Car Forums banner

1 - 11 of 11 Posts

·
Registered
Joined
·
365 Posts
Discussion Starter #1
Does anyone have the CAD drawing of the AEV6505A Contactor (Nissan Leaf).

I looked around on Panasonic's website, but I could not find one that was close:
https://www3.panasonic.biz/ac/e/control/relay/vehicle/ev_special/index.jsp

Interestingly they are filled with hydrogen and use a permanent magnet to extinguish the arc.

Which means they are polarized, current should only flow from one terminal to the other.

https://www3.panasonic.biz/ac/e_download/control/relay/vehicle/catalog/mech_eng_ev.pdf?f_cd=301872&via=ok

Thanks,
Wolf
 

·
Registered
Joined
·
1,364 Posts
Interestingly they are filled with hydrogen and use a permanent magnet to extinguish the arc.

Which means they are polarized, current should only flow from one terminal to the other.
Please excuse my ignorance but do you have any links/data to show the contactors are polarized? Any markings on the part itself (I can't see them)?
 

·
Registered
Joined
·
365 Posts
Discussion Starter #3
Please excuse my ignorance but do you have any links/data to show the contactors are polarized? Any markings on the part itself (I can't see them)?
On the side of the contactor are two torques (star) screws.
Remove these, and the metal bus bar will come out.
Then you will see a + and a - molded in the plastic below the copper terminals.

Around the 9:30 mark in this video I take out one of the bus bars:
https://youtu.be/sd85b4mwrPE

Hope that helps,
Wolf
 

·
Registered
Joined
·
4,051 Posts
Kevin,
Likely it has arc suppression inside like other contactors. These are magnets that essentially push the arc away from the contacts, quenching the arc. If it was in backwards, it would essentially pull the arc towards the magnet. Contactor contacts with arc suppression are polarity sensitive, not because of the contacts, but because of this magnet.

You're right energy goes in both directions, but it's likely you'd pull a larger arc under load than under regen.
 

·
Registered
Joined
·
35 Posts
Hey guys,

Can anyone confirm some main infos on the main contator on the Leaf?

Rated 250amps?
12 voil coil?

Do you guys think I would need to use precharge if use on 56v at about 150amps?
 

·
Registered
Joined
·
365 Posts
Discussion Starter #8
Yes, 250A contacts (probably actually 300A).

Yes, 12V coil (You will want to add a flyback diode across the coil, and PWM it at around 6V once the contactor has closed).

Yes, you will need a pre-charge resistor, its the current that welds the contacts.
 

·
Registered
Joined
·
35 Posts
Yes, 250A contacts (probably actually 300A).

Yes, 12V coil (You will want to add a flyback diode across the coil, and PWM it at around 6V once the contactor has closed).

Yes, you will need a pre-charge resistor, its the current that welds the contacts.
So the flyback diode is to reduce the voltage on the coil... Is the benefit is to reduce energy usage or making the coil last longer?

As for the precharge, do you really think I would need the precharge for my system though? It only be only to SHUT off and disconnect power when it's underload... maybe 5-150amps max under load. I recall you mention that you probably don't need precharge if you're opening the relay? Does 48v inverter pull massive power upon contact? I know it spark a bit when I connect power, but I don't recall it's a major spark...

The reason why i don't want to do precharge is it would complicated thing, since I would need to add the step start right?

I was planning to have just a digital voltage meter that control a 12v source to turn on or off the relay base on voltage.
 

·
Registered
Joined
·
365 Posts
Discussion Starter #10
The flyback diode is to protect your mosfet/transistor/relay that is switching the contactor.
With out the flyback diode you end up with a high voltage spike on the contactor coil.


The contactor opening under load is what it is designed to do, it has a magnetic arc suppression.
But this does not work when the contactor is closing.

I don't know what inverter you are using, but I assume that is has a large bank of input filter/bulk capacitors.

Charging these capacitor are what causes the inrush current that can wield the contacts in the contactor.

System voltage does not matter, since connecting a discharged capacitor to any battery is a momentary short circuit (current is only limited wiring/battery resistance).

I recommend that you have a pre-charge circuit.
 

·
Registered
Joined
·
365 Posts
Discussion Starter #11
I actually forgot about this thread...

I could not find a 3D model of the AEV6505A Contactor, so I made one:


Let me know if you need the 3D model. :)
 
1 - 11 of 11 Posts
Top