I think my viper 10 blew up

[Kazzer]

Hi David,
Any word from Mtroniks about the ESC I sent to you to go back with yours? Thanks, Bob

Pose the question on the Mtroniks forum and deal with them directly please.

Keep this stuff separate and focused on the product manufacturer, otherwise we'll all get screwed up.

[639mpa]

This is beginning to sound like a bad batch of ESC's. Send it to me and I'll forward it, along with an ESC that blew on me, to MTronik's for some answers.

David D Merriman lll
835 Holly Hedge Ave.
Virginia Beach, VA 23452

Hi David,
Any word from Mtroniks about the ESC I sent to you to go back with yours? Thanks, Bob

[639mpa]

The new ESC has been working pretty well up to yesterday when I noticed the external BEC was getting hot thru the subdriver wall. I haven't noticed this before. Tonight I had the same thing. Didn't notice any shorts but I get a lot of chatter from the blow/vent servo with the stick in neutral. I'll have to troubleshoot with the ET's and MM's. Also, it got warm enough to melt the glue that holds it to the ESC body. No visible damage anywhere.

Things always get better after ORSE

Thanks

[He Who Shall Not Be Named]

This is beginning to sound like a bad batch of ESC's. Send it to me and I'll forward it, along with an ESC that blew on me, to MTronik's for some answers.

David D Merriman lll
835 Holly Hedge Ave.
Virginia Beach, VA 23452

[639mpa]

MY new ESC SUB10 just went toast. I hooked it up and ran it for a few seconds and all was fine. I then got a very fast beeping sound from the ESC. ????? I have a 10A fuse in the line from the battery to the ESC. It blew. Checked all the wiring and connectors visually. All were ok. Inserted another fuse, flipped on mission switch-blown fuse. Replaced fuse. Disconnected ESC from power wires. No blown fuse when powered on with mission switch. Disconnected ESC from motor turned on mission switch and the ESC lit up crackled and smoked. New to this hobby and smoked my first and hopefully last ESC!!!! Where are the ET's when you need them? Any ideas? Is the warranty void if you solder motor wires from the ESC to the motor terminals? I'll send mine back so they can do a post mortem. Thanks

[Subculture]

Choice of boat is very subjective.

Even very large boats can get round in fairly modestly sized pools, although you will arguably have far more fun with a smaller nimble model. The Summer Dive-in I have run over the past two years is held at St Albans Sub Aqua club, and makes use of their club house pool, which was once the old cities municipal swimming baths. It isn't huge at 100x60ft, but two Engel Typhoons were quite happily swimming around in it.

Clearly very small boats won't suit big lake diving too well, as they'll disappear if taken out more than a few feet from the bankside.

Here in the UK, most people tend to go for 1/60-1/72nd scale for Nuke attack class boats, 1/96-1/100 for bomber boats, 1/32-1/48th for WWII vessells, and a few larger scales 1/9-16th for midget boats etc.

Those scales tend to result in a boat that will fit in the back of an average sized car, although there are exceptions.

Andy

[Kazzer]

On the flip side, you have an extra piece of kit to fail, win some lose some. If you're sailing in fairly shallow ponds or swimming pools, then I would just use the ESC BEC. Big lakes or ponds, I might look towards the separate route.

As The Wiz and I are probably the only model submarine supplier that caters to a large range of boats and consequently attract more 'newbies' to the hobby, we frequently have people very unsure of which model to purchase. They seem to not consider where they are going to sail their boats, and often choose a model which is really unsuited to their particular puddle, so I'm pleased to see Andy make this distinction.

Since we developed the Snort System, neither Mr. M or I ever fill the gas bottle if sailing in a swim or paddling pool, as we can easily recover the boat. I'd like to develop some sort of chart to show which boats are suitable in which environment, and consequently which failsafe and ballast systems are required. I haven't quite got it all figured out yet, so if you have any ideas, I'd be grateful for any input.

[Subculture]

I would much rather have a boat stuck on the bottom with a blown fuse, than an onboard fire turning my expensive wtc and hull into a novelty fondue kit.

Regarding the problem of ESC internal BEC's and a blown fuse making your sub dead in the water, the only way around this is to fit a separate BEC, and fuse that too.

This way if a fault develops in the ESC, you will still be able to blow your tank etc. With good quality BEC's available for under $5, it makes good sense to me, added to this, they're tiny and will fit in all but the smallest of models (you'll probably struggle with the Revell Skipjack wtc).

On the flip side, you have an extra piece of kit to fail, win some lose some. If you're sailing in fairly shallow ponds or swimming pools, then I would just use the ESC BEC. Big lakes or ponds, I might look towards the separate route.

[He Who Shall Not Be Named]

Thanks, Andy.

If I hear it from you or Kevin McLeod, then it's gospel to me. I'll take your advice.

This morning I plugged in an 'old' Viper Sub 10 ESC into the system and it all worked well. Me thinks we have a bad batch of ESC's out there in submarine land. But, final say-so on that theory will be made by MTroniks after they examine the bad units me, Dalton and others send in.

Good stuff, Andy!

David,

[Subculture]

That's it. And go for a slow blow version. It won't save the controller if something goes, but it will save your wiring and your wtc.

50A at 12volts is 600 watts- well that's a serious fault or a very powerful motor (going for the Subdog record?) before the fuse goes pop.

[He Who Shall Not Be Named]

I can present no valid argument against your advice here, Andy.

So, a 50 Ampere fuse ahead of the ESC is what you're saying? (The Sub Viper 10 is rated for a maximum motor draw of 40 Ampere's).

Oh, and did the pictures show up for you in the above post?

Thanks for the help, by the way. As usual, you're the go to guy for serious, well thought out, no bull-**** answers.

David,

[Subculture]

I wouldn't use any power system unfused. Nuisance blowing is generally the result of poor speccing of the fuse. A correctly specced fuse (25% above the maximum current draw of your system) of a slow blow variety will prevent onboard fires. Without the fuse, your cabling becomes the 'fuse'.

Ramesh runs his boats sans fuse, ask him what happened to his Lafayette a couple of years ago when his ESC went short circuit.

[He Who Shall Not Be Named]

Andy,

I just 'attached' those missing shots to the bottom of the narrative. Hope they show up for you.

A valid question. And one of my terrible little secretes will be revealed below.

You SOB! You're about to make me look like a jerk now ...

... No, no fusing.

Typically, the fuse goes between the ESC and the motor which, in this case, would not have mattered: the ESC blew up before any current was directed to the motors. And if you fuse ahead of the ESC and the fuse opens up on you, then you lose all system propulsion and control power (the ESC routes battery power to the BEC) with the likelihood of losing the boat. I you fuse behind the ESC then you protect the ESC from excessive motor draw and retain power to the BEC and the devices it feeds, so you can get the boat back (either through transmitted command or fail-safe function).

I don't fuse protect my system.

There!

Happy??....


David,

[Subculture]

Can't see the attachments, but have you got a fuse in the circuit?

[He Who Shall Not Be Named]

Well, now you can add my name to the list of guys, like Robert and Dalton, who have had the Viper Sub 10 ESC blow up on them.

I was outfitting a GATO SubDriver this evening (the acrid smoke smell still clinging to my hands and shirt). As I added devices to the motor bulkhead I periodically attached a 7.4-volt battery to the ESC to power things up and check for proper operation of the system. All was up and working until I switched from a 7.4-volt battery and went with the 11.1-volt battery, that Ellie and I got a bit of a fright: the instant I closed the mission switch and, Whaaammo! ... the ESC epoxy case cracked and spewed molten solder! I disconnected the battery pronto and quickly touched everything, looking for heat, an indication a dead short somewhere. Only hot-spot was the ESC -- the entire aluminum heat-sink was 'warm'.

Now, as I understand it, the Viper Sub 10 is good to go at 12-volts. The 'incident' occurred at 11.1-volts. The ESC had been working fine for a couple of days, with repeated temporary hook-up to 7.4-volts as I conducted the device installation and check-out steps. This particular Viper ESC **** the bed only when I hooked up the 11.1-volt battery.

As Steve, our very responsive and helpful MTroniks representative, suggested, I'm going to box up the ESC and send it to their facility for a proper postmortem.

Now, with a history of like failures of this specific ESC (Robert, Dalton, and me) on record, I would suggest ... and this is an educated guess, not at all conclusive ... that we have a bad batch of ESC's in the pipe-line.

Below are shots to better illustrate the situation, as I experienced it:

The failed ESC still hooked up and configured when it suffered a catastrophic failure. Ellie is pointing with the X-Acto knife blade tip the location of the crack atop the ESC epoxy potting material. It was through this heat caused crack that molten solder spewed forth. Note the burns on the heavy gauge power cables leading from the battery -- the insulation on the cable wires did not fail as a consequence of hot wires, the burns were caused by the hot solder squirting out of the ESC case. Yikes!



This shot, a block diagram, is a representation of the wiring arrangement used in the GATO installation -- this for Steve, so he has a better idea how I hook-up the ESC with the other devices. Note that the battery is wired in parallel with the ESC, the LPB electronic switch, and the Lipo-Guard (low voltage detector).



The ESC went tits-up the moment I switched from a 7.4-volt battery to a 11.1-volt battery. WTF?!....

Here are the two batteries used.



Close-up of the spot atop the ESC case where the molten solder shot out. Note that I've removed the heat-shrink tubing from the three-device parallel wiring point. I was looking for alternative sites from which solder would have melted and dribbled onto the ESC case. Such was not the case. Closer examination revealed that the sole source of the molten solder was the epoxy resin encapsulated ESC board.



One final look at the device arrangement on my GATO SubDriver.



Steve: I'm boxing up this ESC and will send it directly to your factory tomorrow morning. And may I say now how much I appreciate your interest, and efforts to put this situation right. MTroniks is a great vendor, and I simply love your product line.

David,