Model Boat Mayhem
Mess Deck: General Section => Model Boating => Topic started by: jaymac on September 23, 2013, 03:58:50 pm
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Having got myself a rtr Pt 569 3x motors 1esc was surprised it had no fuses . Ran it dry all working . Fitted a 40amp fuse cos thats whats in my Wiesel switched on the r/c and plop fuse gone tried another same agin . removed fuse setup tried and all ok tried in the water for a few minutes nothing burnt out .Though a disaster in other ways to be discussed in another topic
Before I start taking things apart ie disconnect a motor or 2 major task for me
any other thoughts on causes
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Can you draw your circuit and where you fitted the fuse exactly?
Was it in the main line coming from the battery to the ESC or elsewhere?
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Hi in the main Positive from Batt to Esc
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You must be taking over 40 amps. After that experience, I would have put a meter on the line to test the amps !!
Ken
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Silly question time - it IS a 40A fuse?
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Ken my little meter only does 10amps
Malcolm thats what it says on the packet
Blade Type Auto Fuses 40 Amp
Maybe thats why Graupner dont fit any
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what motors are they? can you get in to see? What battery and connectors are fitted
and what is the ESC rated at.
john
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John I have no info on anythings rating all is accessible and they look as big as my graupner 600 The Battery is 8.4 nimh
there is a Pic here of one of the motors
http://www.modelboatmayhem.co.uk/forum/index.php/topic,44816.0.html (http://www.modelboatmayhem.co.uk/forum/index.php/topic,44816.0.html)
(http://i152.photobucket.com/albums/s161/jaymac_port/P1000204copyjpg596Coupling2_zps337c3872.jpg)
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If I'm not mistaken they look like there johnson 550 motors and under test I have had a draw of 20amp under load from one of these motors
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I'm saying it blows without any load ie no motors turning and instant on power on
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As grasshopper suggests......."Can you draw your circuit and where you fitted the fuse exactly?"....from you latest comment it sounds like a dead short wiring fault :embarrassed: ......
Possibly best to let a multi meter walk over each wire in the circuit/s......... Derek
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Derek its simply in the positive lead from the battery to the esc a dead short ? possibly but I would expect some sign of that running without the fuse .Only guessing. Multis are only for checking batteries for me :} not mastered owt else
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Derek its simply in the positive lead from the battery to the esc a dead short ? possibly but I would expect some sign of that running without the fuse .Only guessing. Multis are only for checking batteries for me :} not mastered owt else
If the fuse is in the supply line from the battery how can you be running 'it' without the fuse in?
Is there a separate supply for the RX (and servos) and it is only those you are 'running'? In that case the esc is probably duff.
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Can relate to your difficulty with multi meter etc, as I am not a lecky, or brilliant with wiring, as some others are on this forum, but your description does seem to indicate a dead short.
The suggestion to draw up the circuit, is a sensible starting point, as all else is pure guess work/speculation.
There are some really helpful "electrically" capable forum members and a drawing will help them help you. O0 O0 O0
Not to mention us others, who want to learn and do not want to fall into the same pitfalls.
Don't know if photo of the actual fuse setup may assist or not but you never know.
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I am not suggesting checking current draw as you have previously indicated a 10 Amp limitation
Having said this....a compact multimeter will check for stray conductivity ;D & I also have very limited knowledge of electrons & their mysterious black paths........ {-) Derek
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subscribe to this one
a photo would do in stead of a drawing
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If the fuse is in the supply line from the battery how can you be running 'it' without the fuse in?
Is there a separate supply for the RX (and servos) and it is only those you are 'running'? In that case the esc is probably duff.
The connectioin twixt batt and esc by tamiya I simply fitted Tamiya extension and then fitted Fuse in th positive leg To run without fuse just remove extension . There is no seperate feed for the RX though have a feeling in me water the R/c Saturn might be a bit iffy . Will knock up a rough drawing later today
thanks for all other input
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I'm saying it blows without any load ie no motors turning and instant on power on
I understand that but was just advising that if solve this problem will have the same problem when underload with a 40amp fuse if they are johnson 550 motors.
plus from your description it sounds like who ever made this boat knew of this fault hence no inline fuses fitted
have you tried fitting inline fuses to each motor rather than from main feed ?
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Hi just going through the early stages of sussing out the cause / Inline fuses to each motor possible last reort . As for whoever built Ha! this is a Graupner premium Line model RTR albeit I never got it first but doubt it had ever been used or tinkered with. for some reason I;m a bit iffy about the RC it is a saturn and nowt much in their manual
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what happens if you disconnect 2 of the motors does it still blow the fuse ?
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Hmm , I'm just wondering if it's a 'momentary' feedback from the E S C ? as it's immediately after switching on . . .
In that case independent fuses to each motor would be the answer, fuses somewhere are a must ,weeds , garbage round the prop etc, will possibly lead to a VIKING death for the electronics or even the boat . . . we've had a few 'smokers' here , electronics mostly . . . it's not a pretty sight watching a grown man CRY <:(
Bill
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what happens if you disconnect 2 of the motors does it still blow the fuse ?
Finding out if there is a dud motor is a good step, as is fusing each of the motors. Not much point fusing a single motor, but when there are 3 of them on the same ESC....
If it blows the fuse with all motors disconnected, it indicates that something is amiss in the ESC causing a massive current drain during switch-on.
I can't see the RX making any difference, it's running off a 5 volt supply from somewhere and has been shown to work OK by the initial tests without the fuse.
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Ok here is the circuit as such
(http://i152.photobucket.com/albums/s161/jaymac_port/596circuit_zpsd4d1c51a.jpg) (http://s152.photobucket.com/user/jaymac_port/media/596circuit_zpsd4d1c51a.jpg.html)
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what happens if you disconnect 2 of the motors does it still blow the fuse ?
No Go area soldered i'm afraid
Off to do a bit of Sailing now Much less complicated :-)
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a pair of side cutters will fix that
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The connectioin twixt batt and esc by tamiya I simply fitted Tamiya extension and then fitted Fuse in th positive leg To run without fuse just remove extension . There is no seperate feed for the RX though have a feeling in me water the R/c Saturn might be a bit iffy . Will knock up a rough drawing later today
thanks for all other input
HI jaymack, drawing that sort of amperage through a Tamiya connector, the connector
won,t last long they are only rated to 15 amps.
john
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A simple cure to try would be to change the fuse for an Anti-Surge type. That may well cure the problem.
Give me a ring on the number in the PM that I have sent to you and I will explain the probable cause of the fuse blowing on connecting the battery.
A digital multi meter may not be fast reacting enough to show the cause of the fault.
Mike.
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If it only blows fuse when extension is used,seems like the wires are crossed?
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hi ya jaymac
just a thought, do all the props and motors turn freely by hand? no tightness in any of the shafts. Have you tried disconnecting the couplings so that the propshafts don't turn, only the motors and tried the fuse in then? see if it pops the fuses,
I know Johnson motors of the 555 type tend to draw between 1.5 and 2 amps running free and that when they start up they can draw excessive amounts of amperage, but I would have thought not enough to blow a 40 amp fuse, even on start up. Also when you are running all 3 motors unfused does the cable from your battery or any of the cables get warm cos if we are thinking the motors are drawing 40 amps or thereabouts, looking at the pics of the cables on your motors, I would be expecting the insulation to start melting, especially when you come to putting the model in the water. I think you might have a naff motor or maybe one of the shafts is tight.
aye
john
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Aye John! ok2
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Must be a nell of an ESC if it's surviving after a 40A fuse is letting go?
Regards Ian.
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Do you have full control on your motors?
Ie. slow to fast to slow OK?
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Do you have full control on your motors?
Ie. slow to fast to slow OK?
Initial start slight stutter then ok and havent run (dry)longer than a few minutes but no sign of heat during that period. Methinks I might try different type of fuse before messing with any wiring. Tried once in the lake damned thing went ok a few feet then went int High reverse = Stern well under a water . some how got it stopped and out . No damage done did think perhaps signal lost and R/C was set to failsafe aircraft fashion which would have caused that but dryland checks everything just stop on TX off or going out of range
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Hello
A few things .
1 A tamiya plug will not handel 40ah for long it will melt.
2 to genrate +40ah you are going to a dead short . Thoes motors would all have to be a stall to genrate that current and even then it might not be enough . but you say you can run for a few min on low power then it went out of control. This means the motors / shaft are free . This is not to say there could be a bit of a bind in them.
There are 2 things it might be.
1 that not a 40ah fues you have . 40ah is not a common car size fues .What colour is your fues?
2 you have a motor on the way out . It may have a bad joint in the comutator. which some times shorts and other times run ok. I have seen this. A Amp test on each motor would point out which one it is.
If you are running 3 motors I would run 3 fues lower rating after the ESC with 1 going to each motor. If a motor stall or fails it will blow that fues and you have 2 motors to get in on. Still keep the main fues between the battery and the ESC.
I have to agree with other a photo would help .
John
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Fuse is orange amber coloured similar to the liquid I'm about to resort to :}
OK just tried this put the extension back in bypassed fuse and its stillok so nowt wrong with the extension? . Now heres the thought for tonight just tried a bog standard domestic 13Amp fuse and it did not blow to my limited knowledge a fuse is ok as long as not used Above its rated voltage only the amp rating governing/ What say?
Thanks loads for all the input slowly digesting
Jay
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is it 40A or could it be possibly 4.0A?
try a 20A or 30A car fuse and see if that blows (should be spares in your cars fusebox - start with the biggest) does sound like the 40A fuses you have may not be (40mA?)
Grendel
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if its one of these - http://www.thetoolboxshop.com/0-375-40-pack-of-10-durite-40a-standard-automotive-blade-fuse-orange-7209.html?gclid=CMTf4v_l5LkCFVMftAodbzwAsw they are 40A continuous rating - 80A blow.
Grendel
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yellow/amber is also the same colour for a 5 amp blade fuse. It varies in colour shade between manufacturer of course. Theyre could be a possible mix up in the pack. Even so to pop a 5amp fuse on intial start up though is a still a large surge.
On the tamiya extension lead have you looked at the tamiya plugs themselves for any stray wire strands that havent been crimped probably possibly causing intermitant shortages across the back of the connetors?
Overall if it isnt any of those and the fact it went into a random reverse id say its a dodgy esc. Maybe a H bridge short.
For those of you who may be interested ive recent purchased myself a watt meter from giantcod, it has 130A limit at 60v. You have to add your own connectors to it but then you simply plug it between the battery and esc, it works great and gives you a live reading of your amperage, voltage and wattage. I reccomend it. :-))
http://www.giantshark.co.uk/product/171035/gt-power-130a-watt-meter-and-power-analyser (http://www.giantshark.co.uk/product/171035/gt-power-130a-watt-meter-and-power-analyser)
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Your power supply is going straight to ground, dead short in one of 4 places, either one of the three motors or the ESC. Disconnect each in turn & switch on, when you have disconnected the one causing the short the fuse will not blow & you will have found the source of the short. Mick B.
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Further to last nights check with a 13 amp fuse which never blew Today I gota new blade fuse 35A due they had no 40's on looking closely at the 35 I'm pretty sure the ones that blew were not 40's despite the labeling and colour much less meat on the link. Anyroad fitted the 35 and NO Blow.
So bath trials commenced ran forward/reverse about 5 mins no immediate sign of heat .Then lost forward drive and but still had reverse . wiggling forward stick no drive but Rudder started responding . then whilst stick fully forward Wham full reverse like i got in the pond Methinks either RC or esc a bummer,
As I have no spare esc to try and reluctant to spend my hard earned pension :} till I'm sure its that.I'm going to try with my planet rc tomorrow
Thanks again to all for their input and apologies Moderator if the latter part of this should be a new post
Jay
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No probs Jay.
A very challenging problem which has stretched the old grey noodles a bit. O0 It does sound like a temperamental 'set up' you have there and we 'd be interested in the final solution.
Best of luck
Ken
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Think I got the final solution the 'blinking!' Esc is dead now :((
Today i rmoved the RX over to another boat tried it in that very strange happenings could not really get the throttle and rudder working on the correct sticks. once when I had the throttle ok on the left stick any lateral movement moved the rudder . Thought aha it might be the rc thats at fault so Plan B fit my planet Rx in the PT looked promising for a few minutes the the Batt died >:-o
Replaced batt then lost all power no fuse blown but as far as I cn check no power out from the Esc to the Rx Sooooooo looks as if a new Esc or two is required
any suggestions on that front welcomed
i do have a pair of esc;s in an unused boat thinking using them on just 2 of the motors for nowjust to at least get the damn thing going. What a wonderful relaxing Hobby this is
Jay
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Well Gentlemen with fingers and everything else crossed methinks I have won
The fuse problem was undoubtedly a Red Herring Albeit time consuming
I have just fitted a new Esc and on switch on all ok on dry running all ok none of the glitches of previous when I could run
Finally I done 2x 5 mins trials in the bath and all seemed fine no heat in either 3 motors or Esc . Hopefull some lake trials soon
Again Thanks to all who contributed much appreciated
Jay
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:-)) :-)) :-)) :-))
ken
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well done Jay, these problems crop up I think for most of us at 1 time or another
I have had my fair share.
:-))
john
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Any reason, you have not mentioned the brand/type of ESC at fault????
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Any reason, you have not mentioned the brand/type of ESC at fault????
Hi yes simply because it is unbranded as are the motors but this is on a Graupner Premium line PT596 RTR which retails for over £400 . As I did not buy it new dont want to badmouth it too much but believe me everything on it was brand new. luckily I paid much much less than that for her
Jay
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Hi yes simply because it is unbranded as are the motors but this is on a Graupner Premium line PT596 RTR which retails for over £400 . As I did not buy it new dont want to badmouth it too much but believe me everything on it was brand new. luckily I paid much much less than that for her
Jay
:-)) :-)) O0 O0
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brand name BLOW up too see my post
blown up 8 esc >>:-(
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IF the fuse only blows you are lucky ,as what Old Shrimper was saying we have seen 8 of these go off like this no crossed wires ,in the end you start to get a sweat up ,wondering if you will blow the fuse first or the ESC,,,fun and games,,,,,