Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Other Technical Questions... => Topic started by: goBulawayo on November 20, 2012, 06:21:28 pm

Title: Problem with connecting ESC, Battery, Motors
Post by: goBulawayo on November 20, 2012, 06:21:28 pm
Hi Guys, rebuilding a Hooben Perkasa and I have just taken delivery of a 12v gel battery, now I connected it all up and I cannot get anything to work via Tx.

When i connected it all up with a 6v pack, I get a red and green light on the ESC (photo 1) and when I turn on the transmitter the motors turn when stick pushed forward. However when I connect the 12v battery I only get a red light (both flash on connecting the power but then the green goes off) see pic 2 - Pic 3 shows the ESC - When I accidentally connected the battery wires red to black and black to red the motors ran instantly, I assume this is because the  ESC is Fwd only?

Any suggestions please, Thanks

Wayne

(http://i297.photobucket.com/albums/mm223/gubulawayo/IMG_9546.jpg)
(http://i297.photobucket.com/albums/mm223/gubulawayo/IMG_9547.jpg)
(http://i297.photobucket.com/albums/mm223/gubulawayo/IMG_9549.jpg)

Title: Re: Problem with connecting ESC, Battery, Motors
Post by: DickyD on November 20, 2012, 06:49:05 pm
Your ESC is an aircraft one and you dont see many planes flying backwards.(http://i124.photobucket.com/albums/p8/DickyD_photos/Smileys/Mail2.gif)
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: goBulawayo on November 20, 2012, 07:28:51 pm
Yep quite right, problem is I cannot get it to go forwards even!!   >>:-(

Wayne
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: Stavros on November 20, 2012, 10:52:34 pm
Going by your own admission of connecting the wires incorrectly ,personslly I think you have cooked it and it is scrap
 
 
Dave
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: goBulawayo on November 21, 2012, 06:15:08 am
Thanks Dave, problem is it still works when connecting the 6v pack?

Wayne
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: Netleyned on November 21, 2012, 07:39:12 am
A new 12V fully charged SLA will be nearer to 15 Volts than 12.
Could the esc be shutting down on overvoltage?


Ned
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: essex2visuvesi on November 21, 2012, 07:59:57 am
A new 12V fully charged SLA will be nearer to 15 Volts than 12.
Could the esc be shutting down on overvoltage?


Ned

Seconded I was going to post the same thing, but you beat me to it
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: malcolmfrary on November 21, 2012, 12:56:32 pm
Quote
When I accidentally connected the battery wires red to black and black to red the motors ran instantly, I assume this is because the  ESC is Fwd only?
If its a Fwd only one the motor may have fired up via the protection diode or the intrinsic diode built into the output transistor, and if kept brief, may have saved the ESC, but usually a reverse power connection results in toast.
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: Netleyned on November 21, 2012, 02:04:46 pm
f its still working ok on 6v it aint toast  :-))

Ned
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: goBulawayo on November 21, 2012, 03:31:21 pm
Thanks Guys, If it is putting out 15V, how do I reduce the voltage? I think my multimeter can check a 12v battery, will have to see (I know nothing about these sort of things) but I am sure it has a selection with a 12 over some solid and dashed lines - My battery is a gel cell type I assume this type could still be putting out 15V as it is new?

Thanks, Wayne
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: goBulawayo on November 21, 2012, 06:41:27 pm
Mmm cannot find any setting with 12v on the multimeter, perhaps its not suitable - Photo below, can anyone tell me whether I can check the charge of a 12v battery with this multimeter please

Thanks, Wayne

(http://i297.photobucket.com/albums/mm223/gubulawayo/IMG_9509.jpg)
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: Stormbringer on November 21, 2012, 06:47:20 pm



use the 50 v scale
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: goBulawayo on November 21, 2012, 07:10:13 pm
use the 50 v scale

White or yellow side? Wayne
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: Netleyned on November 21, 2012, 07:17:39 pm
White

Ned
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: goBulawayo on November 21, 2012, 07:25:18 pm
Thanks, me thinks my multimeter is shot - It is just swinging all the way across the screen when measuring on 50v and the same on 250v - I opened it up to change the battery and the - wire fell out, looks like it has corroded away. Time for a new one

Wayne
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: CF-FZG on November 21, 2012, 10:16:48 pm
A new 12V fully charged SLA will be nearer to 15 Volts than 12.
Could the esc be shutting down on overvoltage?

So does a 10cell Nixx pack and the esc's rated for that.


Question for Wayne - have you set it up according to the destructions??


Mark.
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: goBulawayo on November 22, 2012, 06:17:51 am
Umm destructions, no I didn't have any - this was a freebie ESC - did not realise it would have had them - What might I have needed to do other than connect the wires?

Wayne
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: essex2visuvesi on November 22, 2012, 06:55:12 am
http://www.mtroniks.net/resources/Sonik4Instructionsheet.pdf

Those might help
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: goBulawayo on November 23, 2012, 10:05:30 pm
Tried the Mtroniks instructions - I have also emailed mtroniks as I am having no joy - I wonder if the receiver is not suitable for 12v as the L-R stick does not operate the rudder servo when connected to 12v, though it works OK on 6v

Wayne
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: catengineman on November 24, 2012, 12:17:11 am
Just a small question
Are you delivering 12 v to the receiver? if so that is why there is nothing going on but does at 6v the Rec will only work with 6v so you will need to have a separate 6v supply to the rec OR get an ESC with a bec (battery elimination circuit)


If I'm wrong don't soot me I am an engineer so "xxxxx" and smelly Apparently!
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: goBulawayo on November 24, 2012, 07:43:06 am
Thanks catengineman, how do I stop the ESC delivering power to the Rx? I have the battery connected to the ESC, teh ESC connected to the motors and the Rx and I have the rudder servo connected to the Rx

Wayne
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: catengineman on November 24, 2012, 08:53:05 am
If you remove the red wire from the plug on your ESC then get a 6v battery pack and plug it into the rec your 12v supply should only go to the motor and the 6v system will drive the ESC and any servos you have in the system


It's worth a try to see if the  ESC you have is shutting down because of some slight fault within


R
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: goBulawayo on November 24, 2012, 10:21:20 am
Thanks R - I will send the ESC off to MTroniks first before cutting any wires

Wayne
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: DickyD on November 24, 2012, 10:34:18 am
Dont cut the red wire, remove it from the plug using a pin and tape it to the cable so you can reconnect it if needed at a later date.
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: malcolmfrary on November 24, 2012, 11:14:43 am
Thanks, me thinks my multimeter is shot - It is just swinging all the way across the screen when measuring on 50v and the same on 250v - I opened it up to change the battery and the - wire fell out, looks like it has corroded away. Time for a new one

Wayne
Yes, its broken.  It looks like the internal circuit that looks after the ranges is no longer a working circuit.
On a working one, you can measure any voltage below what the scale says. 
The dash with dot underline is a universal symbol for DC, so that is what you would use around batteries. The "~" is the symbol for AC. 
Setting for too high a scale will just make the needle give a small travel on a low voltage, moving to a lower scale gives bigger travel and is easier to read.  Making the needle travel too far too fast will kill it.  A needle meter does not need batteries for reading voltage and current.  The batteries are for the resistance scales, which are also very useful for checking whether the meter and leads are fit for use.
If you get a digital one, you get the same ranges, but the results are presented as numbers, thus easier to read.  Usually, they don't care which way round the leads are connected, the display just shows a "-" if its reversed.  The downside is that they need a battery to work at all.
Without a working one, when trying to track electrical faults, you are just guessing and hoping for good luck and magic.
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: RAAArtyGunner on November 24, 2012, 09:29:10 pm
Yes, its broken.  It looks like the internal circuit that looks after the ranges is no longer a working circuit.
On a working one, you can measure any voltage below what the scale says. 
The dash with dot underline is a universal symbol for DC, so that is what you would use around batteries. The "~" is the symbol for AC. 
Setting for too high a scale will just make the needle give a small travel on a low voltage, moving to a lower scale gives bigger travel and is easier to read.  Making the needle travel too far too fast will kill it.  A needle meter does not need batteries for reading voltage and current.  The batteries are for the resistance scales, which are also very useful for checking whether the meter and leads are fit for use.
If you get a digital one, you get the same ranges, but the results are presented as numbers, thus easier to read.  Usually, they don't care which way round the leads are connected, the display just shows a "-" if its reversed.  The downside is that they need a battery to work at all.
Without a working one, when trying to track electrical faults, you are just guessing and hoping for good luck and magic.

Do you get any warning that the battery in a digital meter is on the way, out or does it just stop working.
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: malcolmfrary on November 25, 2012, 09:45:57 am

Quote
Do you get any warning that the battery in a digital meter is on the way, out or does it just stop working.

On one of mine, the "-" turns into a small "batt", then the display goes wonky.  A few months later.  This usually only happens when I have forgotten to switch it off for a few days.  Used properly, battery life in service is pretty much the same as its shelf life.
The best thing to do with any meter is to switch it to a resistance scale and tap the probes together before use.  If it reads anything other than zero, something needs checking.  From experience, immediately after doing that check is the time to switch to the intended range.  Saves the hassle associated with offering the resistance measuring circuit to a voltage.
Each design has its own little differences, I wouldn't be surprised if there was at least one that could self check its own battery, but I suspect it would be at the upper end of the market.
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: RAAArtyGunner on November 25, 2012, 10:09:39 am
 
Thank you  :-)) :-))
Title: Re: Problem with connecting ESC, Battery, Motors
Post by: essex2visuvesi on November 26, 2012, 12:13:30 pm
I wouldn't be surprised if there was at least one that could self check its own battery, but I suspect it would be at the upper end of the market.

My cheapy market stall one (£4.99 about 5 years ago) does that.... remove battery cover, switch on and poke negative and positive battery terminals.  Gives a combined result of the 2 AA batteries in the holder :)
Also according to the instructions the display on mine flashes when the battery is low