# pb-6 micro switch wiring



## otp57 (Feb 7, 2012)

I am looking for help on the pb-6 micro switch hookup.
take a look at this circuit http://evhelp.com/Wiring_Diagrams.htm it look to me that the power to the controller is being turn on and off with the pb6, turning the controller on and off many times like that, is that good for the controller or am i misssing something?
I was thinking the the controllor stay on and the (KSI) circuit controlls the start of the controller. why cycle the controller????????


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## onegreenev (May 18, 2012)

The micro switch actually cuts out the contactor coil when you lift off the throttle. To me that is just to much on/off for the contactor. I do not use a micro switch to turn on and off the contactor every time I remove my foot from the throttle. Have a look at the wires and you will see that the micro switch connects to the contactor coil. 

Pete


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## otp57 (Feb 7, 2012)

onegreenev said:


> The micro switch actually cuts out the contactor coil when you lift off the throttle. To me that is just to much on/off for the contactor. I do not use a micro switch to turn on and off the contactor every time I remove my foot from the throttle. Have a look at the wires and you will see that the micro switch connects to the contactor coil.
> 
> Pete


 Ok how would one hook up hook up the micro switch?


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## otp57 (Feb 7, 2012)

otp57 said:


> Ok how would one hook up hook up the micro switch?


 curtus manual states.

*Throttle microswitch​*Curtis PMC potboxes and footpedals are typically equipped with microswitches.
It is recommended that these switches be used to open the main contactor and the
controller​​​​’s KSI input when the throttle is fully released. This adds a level of safety
protection by disconnecting battery power from the motor and controller whenever
the operator releases the throttle. If you are not using a throttle with a builtin​
microswitch, it is recommended that you add one to your system.


So it looks as if the contactor is controlled with the micro switch.
It looks like the contactor is working hard on /off,on /off,on /off and the controller is power off/on the same way??????????????? for some reason this looks bad to me????????????


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## onegreenev (May 18, 2012)

Not totally sure because I don't use one. But at the end of the article it has a setup that shuts off the main power through a secondary main contactor for added safety. It actually shuts of the secondary contactor under no load so there is no real chance to ruin the contactor. I don't like the idea of actually shutting off and turning on the controller so much.


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## Ziggythewiz (May 16, 2010)

I think this all stems from ye olde days when everyone assumed (rightly or not) the motor controller would fail. The thought being it was more a matter of WHEN than IF, so you'd cut power whenever you didn't need it to be safe. From everything I've heard modern controllers fail so rarely it's not worth the extra wear on the contactor.

A good precharge will prevent damage in the event of one of the more common failures anyway (failed controller full on startup).


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## otp57 (Feb 7, 2012)

Ziggythewiz said:


> I think this all stems from ye olde days when everyone assumed (rightly or not) the motor controller would fail. The thought being it was more a matter of WHEN than IF, so you'd cut power whenever you didn't need it to be safe. From everything I've heard modern controllers fail so rarely it's not worth the extra wear on the contactor.
> 
> A good precharge will prevent damage in the event of one of the more common failures anyway (failed controller full on startup).


*Ok so I can tie the micro switch on the PB-6 in the the KSI circuit and tie the emerency switch in the the main contactor?*


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## Ziggythewiz (May 16, 2010)

You'll have to check the manual for your controller, but IIRC my curtis KSI input takes pack voltage, which I wouldn't want to be clicking on and off in the pot microswitch, so you'd want a small relay to do the job, one that's good for at least hundreds of thousands of switch actions.

Yes, an emergency switch should cut power to the main contactor(s).

I have a PB-5, so no micro switch. Controller turns on when I turn the car on, off when I turn it off.


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## mizlplix (May 1, 2011)

The old Jet Industries cars used a PB6 to turn on and off the controller and the contactor with every foot cycle. But they all had an extremely huge Albright aircraft open contactor.

Most people use the KSW to turn on the contactor. The PB6 then turns on and off the 12VDC or 24VDC the controller has a circuit for.(pin ins and pin outs)

My Curtis 1238R has a pack voltage input that must be KSW by use of a relay.
The contactor is operated by the controller itself.

As long as you have a KSW signal to light it up. A contactor to power it up and a manual disconnect just-in-case. You're good to go.

Miz


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## frodus (Apr 12, 2008)

What controller are you using?

You could, if it's an 1238 controller, use the NC contacts to connect the 12V to the common of the Forward Reverse switch. When you don't connect either, the controller doesn't get a Forward or reverse signal, and it's left floating and the motor won't move. 


If it's a DC controller, you can use it to enable/disable the controller.



I've never used the microswitch, don't see the need to really.


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