Weird glitches underway - troubleshooting suggestions

[Slats]

Guys,

I'll run this buy the wider forum group - as I am wondering if anyone has had the same glitches underway and what I could be doing wrong.

The boat / WTC (SD) has been working fine - both on the bench and in the water. On Saturday after about 20 minutes or so - I discovered I had full control over all functions except for the foward propulsion. I had full proportional stern thrust - but none ahead. I pulled the boat out and decided to reset the ESC - thinking its lost its neutral spot. This seemed to fix the boat but on sunday the problem returned in an intermission sort of way. I have never had this problem before, the rest of the boat, rudders / planes / ballast control / LPB (snort) works fine. Battery condition was perfect - showing good charge still left in battery.

Any suggestions what i should be trouble shooting / checking next?

Thanks
John

[VanguardUK]

Guys,

I'll run this buy the wider forum group - as I am wondering if anyone has had the same glitches underway and what I could be doing wrong.

The boat / WTC (SD) has been working fine - both on the bench and in the water. On Saturday after about 20 minutes or so - I discovered I had full control over all functions except for the foward propulsion. I had full proportional stern thrust - but none ahead. I pulled the boat out and decided to reset the ESC - thinking its lost its neutral spot. This seemed to fix the boat but on sunday the problem returned in an intermission sort of way. I have never had this problem before, the rest of the boat, rudders / planes / ballast control / LPB (snort) works fine. Battery condition was perfect - showing good charge still left in battery.


Any suggestions what i should be trouble shooting / checking next?

Thanks
John

Interesting - i've had a similar problem & found I could regain control by swicthing my TX off / on -traced the issue to the BEC & once I installed a separate rx battery pack it solved the problem - I was running on 12v, not sure if this helps at all.

[Slats]

Interesting - i've had a similar problem & found I could regain control by swicthing my TX off / on -traced the issue to the BEC & once I installed a separate rx battery pack it solved the problem - I was running on 12v, not sure if this helps at all.

Yes tried the Tx off / on - no change.
The BEC is on board the M-Tronics ESC is a 1.5 amp one.
I use 7.2V battery. The BEC may not be an issue as the leveller and fail safe still worked and these need 5 volts from the RX, and the RX gets the 5V from the BEC. All other servos etc were working too.

By the way- what ESC where you running that had the BEC issue?
J

[Subculture]

Hmm, this seems to be a recurring problem with these controllers.

A chap I know had exactly the same problem with an mtroniks ESC in his Sheerline Trafalgar. It would start misbehaving after some use.

I considered that it's probably something that is overheating, but these controllers are potted, which makes fault finding interesting!

I suggested replacing it with a controller from another manufacturer, which are in my experience, bomb proof.

[Kazzer]

Stand by! Tech support about to arrive from manufacturer! I guess no one thought to ask them first?

[Albion]

like whose?

[Subculture]

As Number two said- that would be telling (or in other other words if you're really interested email for details).

Mtroniks seem to be decent enough controllers, but they do seem to have a few quality control issues. I believe their newer ranges have dealt with most of the issues people were having.

[Slats]

Stand by! Tech support about to arrive from manufacturer! I guess no one thought to ask them first?

Mike,
Yes I did read the post about tech support, but before I fire off an e-mail to Mtronics I think it my responsibility to ensure that it is indeed a ESC issue.
Sure the symptoms point that way, but IM experience of never having a problem with these ESC, its valuable to ask fellow modelers what they think the problem might be.

E-mail now locked and loaded to Mtronics as next cause of action.
Thanks to all who helped with ESC being probable diagnosis.
John

[Slats]

Mtronics e-mailed.

J

[Slats]

Hmm, this seems to be a recurring problem with these controllers.

A chap I know had exactly the same problem with an mtroniks ESC in his Sheerline Trafalgar. It would start misbehaving after some use.

I considered that it's probably something that is overheating, but these controllers are potted, which makes fault finding interesting!

I suggested replacing it with a controller from another manufacturer, which are in my experience, bomb proof.

Weird coincidence Andy - that its two T boats.

And for the reasons - you outlined above I though perhaps it might not be the ESC - i.e. I only have a current draw of around 1 amp at the slow speed I like to potter along at. Max speed is 3 amps - so did not think o/heating would be an issue- indeed ESC was not even warm

Bomb proof to me is big - i.e. Electronize - I have not seen these in use in subs- how do they go?

Thanks mate
J

[Subculture]

Bomb proof= good design and generously specced MOSFETS.

The controllers are very small- surface mount technology. Different shape to the Mtroniks stuff.

[mtroniks]

Mtroniks ESC queries

Hi. Steve from Mtroniks here.

I've heard that some of you are having some difficulties with our controllers! This surprises me as we designed them to get around most of people's common problems with such products, I'm a bit upset that I hear other manufacturer's units being described as 'bomb proof', but not ours! We need to get to the bottom of what's happening here and fix the root causes.

Very interesting that the BEC is singled out by one of the guys here who's done some testing, this was what came to my mind immediately as I read the comments on the forum. I'm convinced that in most cases here, the BEC is being overloaded. This is a very common problem in sub usage, all the devices that you guys tend to hang off ESC's BECs are often capable, if actuated at the same time, to overload the BEC therefore starving not only these devices of power, but also the speed controller's internal electronics and indeed the receiver! End result, glitching erratic behaviour, etc, etc. The ESC is doing what it's told to do by a receiver that it is incapable of powering, obviously a recipe for disaster! Please be very aware of the ESC's 1.5A continuous/peak current rating, if exceeded, there is no doubt that problems will ensue. Sufficient power MUST be available for these items, it is not good enough to just hope for the best. Several servos, or similar devices operating at the same time can produce current drains that might interrupt the operation of the ESC and receiver, possibly resulting in repeat occurances of the same upon recovery.

With regard to the unit needing 'resetting' ... theoretically possible, although we find that the controllers are extremely resiliant with regard to storing and 'remembering' their setup details, we sell vast amounts of these devices into the model car market, where they are largely regarded as closer to 'bomb proof' than any other manufacturer's devices have ever achieved. It's pretty difficult under such extreme conditions of static electrical charge and lack of easy cooling, to make these things behave consistantly and always remember their setup parameters, but we have absolutely done it. This is a frighteningly dangerous environment for an electronic device, you'll agree if you know your electronic principles. When we move into water most of these horrors are removed.

I see a comment that fault finding on our controllers may be difficult due to our encapsulation processes, have no fear, you'd be amazed! If you have a failed unit, get it back to us via your supplier, we will diagnose and fix the problem.

I hope this has helped!

Steve.

[Slats]

Steve,
I very much appreciate your comments.

I don't think anyone here is poo pooing your product indeed I have been using your ESCs in targets (that's what we sub guys call surface ships) and there has been no problems whatsoever.

The BEC issue, of exceeding 1.5 amps I don't buy.
My sub has 3 Hi-Tech mini (mid sized servos), and a standard servo. For around 95% of the time only two are actively being asked to do something. (rudders and rear planes -via an autoleveller). The ballast standard sized servo is used only when diving and so call that 3 servos in use for a matter of seconds simultaneously. The fourth micro servo uses enagages a micros switch which runs an air pump for surfacing - with the pump on a separate voltage supply to the RX. When this micro servo is running. The ballast servo is at neutral.

I have measured all of these devices under load. Together there near 350 milliamps only less than 1/4 of your ESCs, BEC's 1.5 amps.

I am by no means criticising your product by I also don't buy the BEC argument (which is 1.5amps on your controllers) when large scale targets I have - employ 8 channels or more all through a 1 amp BEC of a different ESC.

Best
John

[Slats]

Hi. Steve from Mtroniks here.

I've heard that some of you are having some difficulties with our controllers! This surprises me as we designed them to get around most of people's common problems with such products, I'm a bit upset that I hear other manufacturer's units being described as 'bomb proof', but not ours! We need to get to the bottom of what's happening here and fix the root causes.

Very interesting that the BEC is singled out by one of the guys here who's done some testing, this was what came to my mind immediately as I read the comments on the forum. I'm convinced that in most cases here, the BEC is being overloaded. This is a very common problem in sub usage, all the devices that you guys tend to hang off ESC's BECs are often capable, if actuated at the same time, to overload the BEC therefore starving not only these devices of power, but also the speed controller's internal electronics and indeed the receiver! End result, glitching erratic behaviour, etc, etc. The ESC is doing what it's told to do by a receiver that it is incapable of powering, obviously a recipe for disaster! Please be very aware of the ESC's 1.5A continuous/peak current rating, if exceeded, there is no doubt that problems will ensue. Sufficient power MUST be available for these items, it is not good enough to just hope for the best. Several servos, or similar devices operating at the same time can produce current drains that might interrupt the operation of the ESC and receiver, possibly resulting in repeat occurances of the same upon recovery.

With regard to the unit needing 'resetting' ... theoretically possible, although we find that the controllers are extremely resiliant with regard to storing and 'remembering' their setup details, we sell vast amounts of these devices into the model car market, where they are largely regarded as closer to 'bomb proof' than any other manufacturer's devices have ever achieved. It's pretty difficult under such extreme conditions of static electrical charge and lack of easy cooling, to make these things behave consistantly and always remember their setup parameters, but we have absolutely done it. This is a frighteningly dangerous environment for an electronic device, you'll agree if you know your electronic principles. When we move into water most of these horrors are removed.

I see a comment that fault finding on our controllers may be difficult due to our encapsulation processes, have no fear, you'd be amazed! If you have a failed unit, get it back to us via your supplier, we will diagnose and fix the problem.

I hope this has helped!

Steve.

Steve - supposing that I am wrong and it is an overloaded BEC? What is the solution to getting the 5 volt rail from the Rx we need to run levellers / fail safes etc.
A)- Use your ESC without its BEC, and plug in a separate battery pack
OR
B) - use your ESC withouts its BEC, and use a separate BEC circuit.

I have to say I find both not an attractive solution. Been there done that (not with your ESC).
A separate battery pack for RX ops is OK - but doing so can be a hassle in the smaller water tight cylinders that we are heading too.

Using the latter option - I am yet to find an off the shelf separate BEC circuit that has more than 1.5 amp capability and is not pedantic over its input voltage. Skip Assay produced one a few years back that did the trick, but I think that had a limit of 1 amp. ???

Steve I am appreciative that you had taken the time to get on the boards here - few manufacturers do.

One of my greatest issues with RC subs IMO is that our requirements for equipment as a rather small segiment of the RC hobby is often not well understood by suppliers. One good example of this - is the near drought of ordinary PPM / FM Radios here in Australia, as the big chain hobbystores start stocking only 2.4GHZ technology that is fine for flyers, RC cars, and model boats, but of no use for submarines. My point here is we tend to be so small per se often our needs are of no consequence to mainstream suppliers and we just have to make do with what is out there. I guess what I am getting at is, if this is a BEC problem, can an ESC be made with a bigger BEC current capacity? To be fair to your product its probably used mostly in fast speed boats - driving just the one steering servo.

All that said - just had my 1/72 Guided missile frigate in the test tank. It runs 6 channels and includes also an amplified sound system. The model weighs around 18 kilos full laddened and uses an 18 volt motor to drive a single 75mm propeller. The wash on to the single rudder which is also huge, causes the servo driving the rudder (a standard Futaba S3003) to go from a 20 milliamp draw at rest (with no prop wash) to 250 milliamps when turning through enough static thrust to pull a grown man off his feet. Our subs control surfaces never experience such treatment - so I just don't buy the BEC argument. This ship uses a 1 amp BEC on board its ESC.

Best
John

[Slats]

Mike if this thread now belongs under Mtroniks section - I don't mind it being moved.

Below is some testing I did tonight with SD1 - My SD that I use in Trenchant.

I had the wife running the radio for this and flicking all the gimbals around on the TX - trying to create as much combined servo throttle functions.

I hung held off a couple of the push rods to the rudders some weights via multi-grips to simulate an extreme load - some 1.5 kilos each!

I rigged up the multimeter on the positive rail between the ESC (with the BEC) and the RX.
Here is the results 0.87 of amp at the absolute maximum.



Is there something else I can be testing to see if in water the amps are higher - exceeding the 1.5 amp BEC?

Best

John