Topic: The need for fuses (Read 6092 times)

Billyruffian · « **on:** January 08, 2008, 01:36:24 pm »

I have read a number of threads that refer to using fuses somehow.

I have a Viper 15 ESC and a 540 motor and have simply made the connections as per the instructions without using any fuses.

Have I done wrong and am I heading for a disaster.

Do I need a fuse and how and where do I put it.

Sorry if this sounds dumb - but I am when it comes to electrics.

Thanks for any help.

BobF · « **Reply #1 on:** January 08, 2008, 01:52:19 pm »

Hi Billyruffian,

If you want to fit a fuse, then it goes in the positive supply from the battery. I suppose that a ten amp would be suitable.

With the Viper esc there is not a lot of point though. (Some will argue with that)

The Viper is designed to cut put if too much load is drawn, so wont burn out for that reason alone. The problem with an esc is that the controller will burn out quicker than a fuse will blow. Also the Viper esc is protected against motor short circuit so no problem there either.
The major problem with earlier msonic controllers was that they would keep going at maximum load until they got so hot they would catch fire. The latest generation cut out before they get that hot.

They were good in fast electric boats where we tend to water cool the controller as a matter of necessity.
When used in scale boats, they tend to be uncooled and work well. The trouble is that scale modelers tend to over load the motor with bigger props and long run times. The average for fast electrics is four to six minutes, where a scale boat can be on the pond for over an hour, with everything getting hotter and hotter. I have seen three scale models catch fire as a result of this on our club pond.

Bob

Colin Bishop · « **Reply #2 on:** January 08, 2008, 01:55:01 pm »

A fuse in the main battery positive line is always a good idea as it can protect from accidental short circuits etc.

barryfoote · « **Reply #3 on:** January 08, 2008, 02:02:04 pm »

For what it is, put one in..Easy to do and cheap so why not?

Barry

Billyruffian · « **Reply #4 on:** January 08, 2008, 02:18:11 pm »

Thanks all.

I will put one in just in case I think.

Tralee · « **Reply #5 on:** January 09, 2008, 09:45:47 am »

Contact FLJ on the Forum he now owns Action who produce an excellent circuit board already fuse for around £20 thus is a fabulous piesce of kit and well worth the money, will also tidy up your wiring if necessary

FullLeatherJacket · « **Reply #6 on:** January 09, 2008, 10:50:29 am »

http://www.modelboatmayhem.co.uk/forum/index.php?topic=6201.0

Review of kit version by Wombat.

FLJ

malcolmfrary · « **Reply #7 on:** January 09, 2008, 12:16:32 pm »

The fuse should be able to cope with the stalled motor, the ESC should be capable of handling rather more. This way the ESC limits the current allowed out to the motor to what is safe for itself. There have been cases where the ESC has an internal fault which passes almost limitless current within the ESC, bypassing the current limiting. Without a fuse in the power lead between the battery and ESC, a fire will result.

Colin Bishop · « **Reply #8 on:** January 09, 2008, 12:25:06 pm »

I always play safe and put a main fuse in the positive battery line and another equating to the motor stall current between the ESC and the motor in case the prop gets jammed by weed or something else round it. Better safe than sorry and the cost is negligible.

Colin

Bryan Young · « **Reply #9 on:** January 11, 2008, 04:55:11 pm »

Quote from: Colin Bishop on January 09, 2008, 12:25:06 pm

I always play safe and put a main fuse in the positive battery line and another equating to the motor stall current between the ESC and the motor in case the prop gets jammed by weed or something else round it. Better safe than sorry and the cost is negligible.

Colin

Snap!Seems such a logical idea that I always wonder why people ask me why I am "double-fused". Do it and save yourself a potential fortune!

Shipmate60 · « **Reply #10 on:** January 11, 2008, 10:28:34 pm »

This is a brand new Viper ESC after its first outing WITHOUT fuses.
An internal short caused this.
Please fit a fuse.

Bob

djrobbo · « **Reply #11 on:** January 11, 2008, 11:09:37 pm »

Hi guys....in my sun xx1 tug i run an mfa 400 on a gear box 2 to i reduction and an electronize esc.......i have caught weed on the prop a few times and every time the stalled motor has popped the 15 amp fuse very quickly.....No damage to the esc at all , so every boat i run now is fused

BobF · « **Reply #12 on:** January 12, 2008, 06:59:25 pm »

Hi shipmate60,

Did you have a fuse fitted to the supply lead featured in the picture of your burnt out controller?

Bob

Shipmate60 · « **Reply #13 on:** January 12, 2008, 08:04:00 pm »

BobF,
I stupidly relied on the internal Thermal Cut Out.
The ESC wast that hot it melted itself and badly scorched the upper deck.
No fuse fitted.
That is why I ALYAYS recommend fitting a fuse.

Bob

Colin Bishop · « **Reply #14 on:** January 12, 2008, 08:48:35 pm »

Isn't it a pity that people can't be fitted with fuses - just think how much trouble would be avoided. ::) (On second thoughts, maybe circuit breakers would be a a better option - a tweak on the nose and they're up and running again as opposed to a minor operation)

DickyD · « **Reply #15 on:** January 12, 2008, 09:08:59 pm »

What are you on Colin ? :-\

Colin Bishop · « **Reply #16 on:** January 12, 2008, 09:28:30 pm »

Sainsbury's 8 year old blended at the moment Richard....

barryfoote · « **Reply #17 on:** January 13, 2008, 08:25:23 am »

I want some of that Sainsburys stuff. It must be good.

Martin (Admin) · « **Reply #18 on:** January 13, 2008, 09:14:18 am »

Can you get low voltage circuit breakers?

barriew · « **Reply #19 on:** January 13, 2008, 10:25:29 am »

Maplin do a range of self-resetting breakers from 1A to 10A. Look for AK07H on their web site. They will reset when the problem goes away. I believe Wingertaz does a 'Press to Reset' version - not sure about the ratings.

Barrie

explorer750 · « **Reply #20 on:** January 14, 2008, 04:47:57 pm »

What fuse would you need to use on a 30A speed controller with a motor that stalls at 43A, and if possable would you advise somewhere I can get them.

DickyD · « **Reply #21 on:** January 14, 2008, 05:00:32 pm »

I know someone will argue with me but I use 15 or 20amp spade type car fuses [ the larger of the two ] and cut the positive wire and fix spade connectors to it. The car fuse is then pushed in the spade connectors.

You can get them all from Maplins.

Works for me.

Bryan Young · « **Reply #22 on:** January 17, 2008, 07:29:08 pm »

Quote from: DickyD on January 14, 2008, 05:00:32 pm

I know someone will argue with me but I use 15 or 20amp spade type car fuses [ the larger of the two ] and cut the positive wire and fix spade connectors to it. The car fuse is then pushed in the spade connectors.
You can get them all from Maplins.

Works for me.

Concur. Spades are quick,easy and cheap. USE THEM...or join the bankrupt club.

malcolmfrary · « **Reply #23 on:** January 17, 2008, 10:58:35 pm »

Quote

What fuse would you need to use on a 30A speed controller with a motor that stalls at 43A, and if possable would you advise somewhere I can get them.

I would have looked for an ESC that could handle the stall current, but, having said that, if stuck with a 30A controller, I would check the current draw under load, hope it was considerably less than 30A, and, that being the case, use the highest value fuse under 30A. As others have said, use spade type connectors and blade type fuses, available most car accessory shops.

Martin (Admin) · « **Reply #24 on:** January 18, 2008, 08:55:34 am »

I was alway of the understanding that the speed controller should be rated near the nominal operating current to give you better speed control. I.e. if the normat operating current of your motor is, say 5 Amps, then you should use a 10 or 15 Amp controller and fit a 10 or 15 Amp "slow blow" fuse to protect it..... is that still true of modern high freqency ESC?!?

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Author Topic: The need for fuses (Read 6092 times)

Billyruffian

barryfoote

Billyruffian

FullLeatherJacket

djrobbo

barryfoote

explorer750