Model Boat Mayhem

Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: timg on September 17, 2013, 11:54:27 pm

Title: Testing an action P80
Post by: timg on September 17, 2013, 11:54:27 pm
Hi All
I have a action p80 speed controller which has an intermittent fault(only turns the motor when switched on ) , i have tried a different radio set ,different battery , all the components and joints on the pcb look ok and the the right colour .
Any ideas how to test the components / ic chip ?
Title: Re: Testing an action P80
Post by: malcolmfrary on September 18, 2013, 09:35:17 am
Assuming that a servo plugged into the slot works OK, that eliminates everything except the ESC. 
If the motor turns on switch-on means that it gives a twitch but has no response to the stick, that is no more than a power-on twitch.  Not at all sure that that should happen.  Does it give the same behaviour if the ESC is left unplugged before power is applied?
It could be that the control part is not responding.  Several possible causes, apart from a dead chip. 

    a   signal wire not connected through, chip doesnt see signal
    b   +ve wire not connected through, chip not powered, can't do anything with the signal
    c    -ve wire not connected through, signal heavily interfered with.

On ESCs with an external BEC, the main battery ground line can have more than one path to the ESC, and this has been known to cause problems if one becomes disconnected. Does it use a BEC or an RX battery?
A servo tester also does a good job of providing a control input to an ESC.
Title: Re: Testing an action P80
Post by: hollowhornbear on September 18, 2013, 09:58:08 am
not sure I understand "only turns the motor when switched on" surely that's what should happen.
look here for instructions ( , have you waited for the speed control to autoset? do you turn on the tx then the rx?
Title: Re: Testing an action P80
Post by: timg on September 30, 2013, 10:36:50 pm
Thanks for the replys,
hollowhornbear,  i have the instructions already because i built it from a kit ,unfortunately no details on testing.
malcolmfray, no bec on mine, not sure which legs on the chip to test ?
if i could buy the same chip would it need to be programmed?
it looks like it will be going in the bin!!!
thanks for your help anyway
Title: Re: Testing an action P80
Post by: hollowhornbear on September 30, 2013, 11:01:44 pm
well the instructions i linked to say the chip is programmed so I would say it will need programming.
could you post a pic of your set up? daft question i know but did you connect the power correctly not reversed ( we've all done it at least once).
do component shop not do the repair/check service that DM did when he owned Action?
I wouldn't bin it just yet.
Title: Re: Testing an action P80
Post by: irishcarguy on October 01, 2013, 05:20:10 am
I think Dave still does the repair work for Component Shop, if not I am sure Dave will set me straight. Don't bin it it is not Chinese & can be repaired that is assuming that it is the problem in the first place, but I doubt it, just wait & see first. Mick B.
Title: Re: Testing an action P80
Post by: malcolmfrary on October 01, 2013, 09:19:50 am
Silly question - the radio that it's plugged into is switched on and powered up?
Title: Re: Testing an action P80
Post by: John W E on October 01, 2013, 03:59:04 pm
hi ya spud
When you say the motor starts up when its switched on; does this mean you connect everything up and as soon as you switch the transmitter on, the motor actually kicks in and starts up without any delay or any presetting?   If so, there are one or two possibilities.   One possibility is that there are 2 versions of this particular speed controller the P80 Condor that is meant for 7 / 12 pole motors and the other version is the P80 Condor which is meant for motors such as the Graupner 540 style 600 speed motors - are you trying to run the wrong motor on the wrong speed controller - this is one possibility.   But, in theory it shouldnt make much difference.
The next one is - on the main output transistors there are 2 heat sinks which clip over the top of the transistors.  There are not touching and shorting out are they?
Third possibility - the chip has a little notch in the top which you will no doubt know all about - as its well documented in the instructions.   Is this the correct way round in the circuit board?
Next - is the signal diode.  I think its the D1 - is it the right way round way on the circuit board? Cos this too can play havoc as well.   I suspect you either have a short on your output transistors where you have soldered them in - so I suggest you double check this or you have fried them.   You will be able to get replacements for the transistors from Component shop - I dont think they cost much. (about 3-4 each plus postage).
So dont bin your speed controller.
Even when you get your output terminals mixed up and you connect your battery terminals into your motor terminals, 9 times out of 10 you fry the output transistors.   The chip, although sensitive to static electricity, normally withstands a moderate amount of abuse and can sometimes withstanding being put in the wrong way, but only when a very small voltage such as under 4 volts has been applied to the battery inputs on the unit.   Most components in the unit will have survived.   
Trick I learned once was when building any kit or electric unit up, when coming to test (after you have done 3 eyeball tests to ensure that you havent bridged any solder joints) or soldered anything in the wrong place or the wrong way around; first test it on a very small voltage.   I keep a naff battery 6 volt gel cel which only holds about 4 volts charge and I use this to test all the kits/bits I have built etc. first along with the old customary fingers crossed.
Title: Re: Testing an action P80
Post by: timg on October 08, 2013, 11:19:44 pm
sorry for the slow reply
Maybe is should have said , that it has been used for the last 4 years with out any problems , the only thing i can think of is its been overloaded ...
thanks bluebird for the break down for testing ,from what you have said the transistors could be fried... i will order a couple of new ones and give that a go
Thanks everyone for their input
i will update after fitting new parts