Sensored has stopped working.

[BeachBuggyPhil]

Speed Passion Gran Turismo 2.1 black edition.
Non of my sensored motors work with the sensor cable plugged in, they all work, but not very smoothly, with it unplugged.
Anything I can do about it?

[sosidge]

Have you tried a different sensor cable? Cleaned the contacts on the ESC sensor socket? Doesn't sound like the motors are the problem since they all act the same.

If swapping cables and cleaning doesn't work, it might be a problem with the ESC itself. You could try re-flashing the software, if not it might be a hardware fault, which means either repair or replacement.

[BeachBuggyPhil]

I've tried as many sensor leads as I have motors.
I have no way of connecting it to the www to update it.
The programming card still works.
I'll run it unsensored, if it's rubbish I'll have to investigate further.

[Cardnim]

Exactly the same thing has just happened to mine.
Works fine in without sensor lead; doesnt work at all with sensor lead.

What Ive tried:

- completely cleaned & rebuilt motor
- checked motor bearings, connections, etc
- tried backup second motor
- replaced sensor board in motor
- replaced sensor lead with brand new COre-Rc one
- placed ESC into blinky mode and reset throttle end points

Downloading the software to re-flash the firmware on the ESC and see what that does but not holdin gout much hope.

Anyone any experience with this sort of thing - good or bad?

Thanks.

[Cardnim]

Just updated the firmware again, and the motor worked in sensored mode for about 10 seconds, then went again.

...so close. damn.

Ideas anyone?
Im thinking the sensor circuitry inside the ESC may have gone, but failing to understand why this would have happened.

[Cardnim]

...now heres a good one:

Found a way to get it to work - I spin the pinion shaft in my hands and it kicks into life, as long as the motor is turning, it works fine.

Once the rotor completely stops, it will not start again until the rotor rotates.

Stranger and stranger....:confuse d:

[Naushad]

That sounds like a sensor board problem I had with a duff SP v2, although you say you've replaced this component.

The Novak Kinetic I had it linked to at the time was clever to pick up whether the fault was at the motor end or ESC...

Maybe you just need to send it to SP/Schuey?

Originally Posted by Cardnim

...now heres a good one:

Found a way to get it to work - I spin the pinion shaft in my hands and it kicks into life, as long as the motor is turning, it works fine.

Once the rotor completely stops, it will not start again until the rotor rotates.

Stranger and stranger....:confuse d:

[benl]

Originally Posted by Cardnim

...now heres a good one:

Found a way to get it to work - I spin the pinion shaft in my hands and it kicks into life, as long as the motor is turning, it works fine.

Once the rotor completely stops, it will not start again until the rotor rotates.

Stranger and stranger....:confuse d:

That sounds like one of the banks of fetts has blown
I recently had the samething happen to an LRP speedo, exactaly the same symptoms.

[Cardnim]

Originally Posted by benl

That sounds like one of the banks of fetts has blown
I recently had the samething happen to an LRP speedo, exactaly the same symptoms.

Arse.
Really appreciate the info guys - thanks.

Im off to cry alot as the wife is sure to cut them off once I tell her I need to buy a new ESC!

[benl]

If its still under warranty they may replace it.
If not maybe worth popping it open to be sure, you should be able to tell if the fetts are gone by looking at them ,they have a kind of burnt bubble (proper technical term that) on them.
Or you maybe better off getting advive from Imull or one of the other proper technical chaps on here, they may even be able to repair it.

[imull]

Before you go opening it, try testing it from the outside! You can't always see a blown FET...

http://www.oople.com/forums/showthread.php?t=102949

There are instructions on how to test the FETs in there, any problems drop me a PM

[Cardnim]

Originally Posted by imull

Before you go opening it, try testing it from the outside! You can't always see a blown FET...

http://www.oople.com/forums/showthread.php?t=102949

There are instructions on how to test the FETs in there, any problems drop me a PM

Cheers for the great advice iMull.

So Ive done what you suggested (I think!) and here are the results:

from +ve battery to motor terminals:
- A,B,C terminals all same
- all showing constant +1
- the second the probe is removed from one motor terminal, the readout shot up to between 6.5 and 10.5 and then quickly dropped to 1 again.

from -ve battery to motor terminals:
- A,B,C terminals all the same
- readout is 2.84 across all terminals

The above was all done with the multimeter set to 20K ohms.

I wasnt sure if I was supposed to "drive" the motor from the ESC, so did a round of results with same setup as above except Im pushing the throttle on the transmitter.

Results with transmitter throttle:
+ve battery to motor:
1 showing constant, then drops to about -5 then quickly increase to 0 until throttle back (when the meter readout returned to +1)

-ve battery to motor:
1 then 0.54 when touched with probes. When throttling, this increases quckly to +1.

I dont even pretend to understand whats happening, but I do know that we are looking for differences across the terminals - and the results showed that all terminals (A,B & C) reacted virtually identically that I could tell.

Does that help at all?!

[RudolfXC]

You also need to test from -ve to all motor terminals.

Sorry, just read that you have done that.

[pugs]

Originally Posted by imull

Before you go opening it, try testing it from the outside! You can't always see a blown FET...

http://www.oople.com/forums/showthread.php?t=102949

There are instructions on how to test the FETs in there, any problems drop me a PM

But what happens if you have a fet that is open and not short???? an open fet might not appear blown as in burn't either because it blows inside across the switching gate and has no outside or visual damage........if it can't turn but do's if you spin the rotor the chances are the one or two of the fets is open..... not shorted out and this might not show on a meter reading because you are reading the working ones in the bank

[RudolfXC]

Originally Posted by pugs

But what happens if you have a fet that is open and not short???? an open fet might not appear blown as in burn't either because it blows inside across the switching gate and has no outside or visual damage........if it can't turn but do's if you spin the rotor the chances are the one or two of the fets is open..... not shorted out and this might not show on a meter reading because you are reading the working ones in the bank

If there is more than one FET for each pole of the motor then if one had gone open circuit, it would tesk OK, and the others would still work and drive the motor, just less efficiently,

If one was shorted, it would test as if all are shorted and probably cause it to get hot with or without a motor connected.

[imull]

Originally Posted by Cardnim

Cheers for the great advice iMull.

So Ive done what you suggested (I think!) and here are the results:

from +ve battery to motor terminals:
- A,B,C terminals all same
- all showing constant +1
- the second the probe is removed from one motor terminal, the readout shot up to between 6.5 and 10.5 and then quickly dropped to 1 again.

from -ve battery to motor terminals:
- A,B,C terminals all the same
- readout is 2.84 across all terminals

The above was all done with the multimeter set to 20K ohms.

I wasnt sure if I was supposed to "drive" the motor from the ESC, so did a round of results with same setup as above except Im pushing the throttle on the transmitter.

Results with transmitter throttle:
+ve battery to motor:
1 showing constant, then drops to about -5 then quickly increase to 0 until throttle back (when the meter readout returned to +1)

-ve battery to motor:
1 then 0.54 when touched with probes. When throttling, this increases quckly to +1.

I dont even pretend to understand whats happening, but I do know that we are looking for differences across the terminals - and the results showed that all terminals (A,B & C) reacted virtually identically that I could tell.

Does that help at all?!

Ok, I might not be as clear as I'd like, I must get round to writing instructions with pictures

You need to have your multimeter set to the highest resistance it can read, 20K won't cut it if the FETs are ok (not that this is a problem but just for completeness) If you're seeing +1 then it's showing that the resistance is higher than meter can show (in your case more than 20K, this is a good thing )

Do the tests WITHOUT a battery and motor connected, as you did originally.

The bottom line is that it appears from your results that the FETs aren't blown, but as PUGS suggests one or 2 might be open. You can tell this by seeing if the resistance is the same on all phases (hence the need to check the top FETs again on a higher resistance setting). If the resistances are the same then there's not a problem, if one is different then this is where the open FETs are.

I hope that makes sense, it's a bit of a brain dump

[imull]

Originally Posted by pugs

But what happens if you have a fet that is open and not short???? an open fet might not appear blown as in burn't either because it blows inside across the switching gate and has no outside or visual damage........if it can't turn but do's if you spin the rotor the chances are the one or two of the fets is open..... not shorted out and this might not show on a meter reading because you are reading the working ones in the bank

You're spot on, my instructions are a little less than thorough

You would see a difference in resistance in each phase though as the parallel resistances would be different.

[Cardnim]

Many thanks Rudolf, iMull and Pugs
Legends every one!!

Will do the legwork tonight and report back.

Im racing tonight, so just going to run it sensorless and hope that I dont make things worse. No choice really, I have no backup ESC, and this is the first chance I'll have to race since the oOple race - Im busting to get out!!

Thanks guys,.

[pugs]

You would see a difference in resistance in each phase though as the parallel resistances would be different.[/QUOTE]

Not quite buddy, because with the meter you are reading the ground and output leg of the fet when testing through the motor and battery wires you would need to test from ground, output and the gate leg with a meter to find the open fet properly as it might not show just from ground and output

Even then it might read the board on the gate leg or switching leg and give a false reading

[pugs]

[QUOTE=RudolfXC;684532]If there is more than one FET for each pole of the motor then if one had gone open circuit, it would tesk OK, and the others would still work and drive the motor, just less efficiently,

Not quite no, it cant switch the open fet at low speed so the motor wont turn unless you spin it to help it on its way, had a few like this, once its up and running the other fets do the work so yeah this is right once its up and running