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[Scottie]

Having seen many posts that describe 'melting' a motor or esc or something I suggestthe following....

Always fit a fuse in your power supply, they're cheaper than anything else.

Scottie.

[krfilby]

Scottie,
          Exactly where in the power supply should the fuse be installed and what amperage for the different ESC ratings for best results. Thanks in Advance.
Keith

[Colin Bishop]

This subject was largely covered last week in the research>Construction Queries>Speed Control Recommendations thread. See here: http://www.modelboatmayhem.co.uk/forum/index.php?topic=1938.msg18922#msg18922 

[Scottie]

Scottie,
          Exactly where in the power supply should the fuse be installed and what amperage for the different ESC ratings for best results. Thanks in Advance.
Keith

Exact location of fuse (or fuses) depends on the configuration of your wiring, motors, ESC, etc. The bare minimum for protection is straight after the battery usually in the positive (red) lead.
To be effective the fuse rating should be slightly higher than 'full load' current but below 'stall' current.
In 'twin motor' set-ups I always put a fuse between the motor and each ESC. This way, if one motor suffers a problem you will not lose all power. Some would say this should be between battery and ESC but I go between motor and ESC so if the esc which is acting as a BEC is overloaded power to the receiver is not interupted and I can get back on just one motor.

Hope this is of help.

Scottie

[justboatonic]

With a configuration of battery - ESC - motor surely the best place for the fuse is between the battery and ESC? As I see it, if the motor stalls, it will draw excessive current from the ESC which in turn, draws the excessive current from the battery. Without protection, the ESC will go 'pop' before anything happens to the motor.

Just querying, mind!

[Scottie]

With a configuration of battery - ESC - motor surely the best place for the fuse is between the battery and ESC? As I see it, if the motor stalls, it will draw excessive current from the ESC which in turn, draws the excessive current from the battery. Without protection, the ESC will go 'pop' before anything happens to the motor.

Just querying, mind!

For a single motor set-up the fuse should be straight off the battery, providing it's the right rating your model and all it's electrics are full protected.

Now consider a model with multiple motors and multiple ESC's... A single fuse has to be rated high enough to cover full load of ALL motors. A single motor stall may overload the ESC without blowing the fuse... Just something to think about.

Scottie.

[Shipmate60]

Without a fuse even controllers that have thermal cut-outs can self destruct, as in pic.

[Scottie]

Without a fuse even controllers that have thermal cut-outs can self destruct, as in pic.

I know, I fell into that trap myself. I got one of the new Mtronic "Viper" 25amp ESC's, read the insturction and thought 'Okay, it's got a cut-out, I don't need a fuse with this one.'  First time out it blew up - enthusiastically - there was smoke everywhere.
All praise to Mtronics though, they replaced it without question.
Needless to say, that was the first and last time I ran without a fuse.

BTW, I can't see the pic - is there something wrong with my settings?

Scottie

[justboatonic]

With a configuration of battery - ESC - motor surely the best place for the fuse is between the battery and ESC? As I see it, if the motor stalls, it will draw excessive current from the ESC which in turn, draws the excessive current from the battery. Without protection, the ESC will go 'pop' before anything happens to the motor.

Just querying, mind!

For a single motor set-up the fuse should be straight off the battery, providing it's the right rating your model and all it's electrics are full protected.

Now consider a model with multiple motors and multiple ESC's... A single fuse has to be rated high enough to cover full load of ALL motors. A single motor stall may overload the ESC without blowing the fuse... Just something to think about.

Scottie.

Right, so you're talking 2 motors on one ESC rather than 2 motors, each with their own ESC? Think I can see which way we're headed now!

[Shipmate60]

That was a brand new Viper.
Says on the packaging 100% Failsafe, but I disagree a tad!!

Bob

[J.beazley]

the picture of your ESC bob doesnt do it justice really they do make a mess as i have seen your repair work.

Jay

[cbr900]

This may seem a dumb question but why are you all having so much trouble, that you need to use fuses are your set ups incorrect, or am I just lucky as for the last thirty five years I have never had a model boat plane or car with a fuse, I have never burnt out anything as yet, if the setup is correct what can be causing all the over heating to cause burn outs....



Roy

[Shipmate60]

I can only put mine down to an internal short as the motors were well within the current rating and I just changed the ESC like for like, but now with a fuse and no problems.
In the words of the song " If it wasn't for real bad luck, I wouldn't have any luck at all"

Bob

[BobF]

Hi all,
I use M Tronic M sonic speed controllers almost withought exception. (One Electronise and one AsTec.) The only problem I can see, (as yet I don't have any Viper series) is that if they are used on scale models and run for long periods of time at near to the amp limit withought cooling, they can catch fire. I know from the fast electrics side of our hobby that some ESC's have thermal cut outs, but I don't think the M Sonics earlier range have.

Bob

[Scottie]

This may seem a dumb question but why are you all having so much trouble, that you need to use fuses are your set ups incorrect, or am I just lucky as for the last thirty five years I have never had a model boat plane or car with a fuse, I have never burnt out anything as yet, if the setup is correct what can be causing all the over heating to cause burn outs....

Roy

Sorry Roy but that's like asking why I have life insurance when I don't expect to die. I've had life insurance for a long time but I still haven't died.

A fuse in a model is the last line of defence against unforseen eventualities - it's insurance for electronics.

Scottie

[DickyD]

When I picked up my new model this week I told the owner of the shop that I had been advised to put a fuse in the circuit to prevent any damage to the ESC. He told me not to listen to everything I was told as" some of these old fogeys dont move with the times " and it wasn't necessary. ??? :-\

Richard

[Scottie]

When I picked up my new model this week I told the owner of the shop that I had been advised to put a fuse in the circuit to prevent any damage to the ESC. He told me not to listen to everything I was told as" some of these old fogeys dont move with the times " and it wasn't necessary. ??? :-\

Richard

Did he say he would happily replace it if it ever burnt out?
I'll bet if you asked he would say no!

This (not so) old fogey is right up with the times and believes the small cost of a fuse is better than total melt-down.

Scottie

[Welsh_Druid]

When I picked up my new model this week I told the owner of the shop that I had been advised to put a fuse in the circuit to prevent any damage to the ESC. He told me not to listen to everything I was told as" some of these old fogeys dont move with the times " and it wasn't necessary. ??? :-\

Richard

He's probably hoping to sell more replacement ESCs  sthat way  

ROY - you said "I have never burnt out anything as yet, if the setup is correct what can be causing all the over heating to cause burn outs..."

I think you have been lucky ? Its the unexpected that causes the trouble. A few months ago sailing my "Mersey" lifeboat it ran aground on a shingle bank some distance away. I got it off but when it came back to me there was smoke coming out of the hull. The twin props in the "Mersey" run in tunnels and a small stone had wedged between one of the props and the hull. Not knowing this I had been running both motors full out to get it off the bank and the jammed up prop caused its controller to melt - literally !  Now I have fuses in ALL my boats. I may not pick up stones again but it can happen with weed or ropes or plastic bags - I have seen all those cause trouble.

Don B

[cbr900]

Welsh Druid,

I guess we are a bit luckier over here as the lakes and dams we sail in have no weed, so we do not really get those circumstances, as for running aground that can happen, but it has not yet been a problem for me as I have often driven several tugs into the shoreline and left them there till some one wanted a go and put them in reverse and backed off with never a problem, I guess while my luck holds out I will leave things as they are........




Roy

[Scottie]

Our major problem is fishing line - those guys just love to throw it in the lake, sometimes it come's complete with hooks and weights.

I daren't say what I'd like to do with their discarded line :-\

Scottie

[Doc]

Fuses are electrical insurance.  And like any insurance, it's only there in case of accidents, or those unforeseen thingys.  I sort of have trouble thinking they are a waste if they never 'blow'.  Where a fuse is placed in a circuit just means that it should protect everything 'down stream' from it.  Sometimes, that isn't the case and is usually because it was placed in the wrong place.  One fuse may protect your electronics just fine.  But, probably won't since everything electrical doesn't have the same capacity (why there are almost always more than one fuse in cars, houses, other stuff).  Multiple fuses can be taken to the totally ridiculous level too.  Sort of depends on how much the protected 'part' costs, how accessible it is, and how lazy you are (lazy and cheap are not always compatible, unfortunately).
Got doubts?  Put the dang thing in there...
 - 'Doc