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[HUNTER]

Dear Shrimper,
I have just had a look at this thread and the photos - nothing wrong that I can see apart from the motor suppression capacitors. I can't quite see the lower cap from the photo where it goes from to where it goes to.
The suppression kit should be one across the two motor terminals and the other two should go from each of the motor terminals to the motor can. The legs of each cap must not touch each other as otherwise a dead short occurs. The legs therefore should be insulated. Can you take an end-on photo so that I can see it please.
Regards
Graham

[old shrimper]

hi mate yes i will get one for you
the thing is that you can run any of the 3 the motor direct from a battery and there  fine one of my motors does not have the little caps
are they really necessary with 2.4htz ?  as theres no one else in our area with a model boat

[B.B]

Hi there  this is how the end of my motor looks (thats how it arrived with suppresser on)  not game to hook up any more ESC's as they all seam to end up in ESC  Heaven   mmmm mabe  HELL as they left in a trail of smoke.......

[old shrimper]

THE motor that does not  seam to blow up so many esc  does not have any biscuits on it ??

[B.B]

Oh well see what the guy's come up with as its out of my league talk about biscuits  I'm going to go and have one with a coffee  ...

[RAAArtyGunner]

Guys,
 
Just to be different, I have one of those MFA motors but it has three "biscuits", just as in the first photo of this post.
 
Motor is Torpedo 500, 4.5V to 15V DC with 6 to 1 Gearbox, and by what I can make out so is the one in the one shown in the first photo.
Just in passing the biscuits are not edible, 

[old shrimper]

yes both motors are the same except for the amount of biscuits
the other motor with no biscuits is an SKU 700 high torque  on direct drive way to much power on 12v it gets my tug up on the plane all most

[malcolmfrary]

hi mate yes i will get one for you
the thing is that you can run any of the 3 the motor direct from a battery and there  fine one of my motors does not have the little caps
are they really necessary with 2.4htz ?  as theres no one else in our area with a model boat

Although 2.4GHz is pretty much immune to radio interference, the back emf's generated by any motor can still cause trouble if they get into the electronics, and if there is nothing to stop them, they can and do get up the motor leads and provide false signal to the electronics.  The biscuits stop them at source, and can be considered a good thing. 
Some manufacturers fit them internally - if you look closely at the tags, you might see a very fine wire disappearing into the casing.

[old shrimper]

ok we are conducting an experiment tomorrow
have installed 2x HK Xcar 45A brushed ESC $10 each running on 2s 7.4v 5000 mAh lipo BATTs
in each of our models they work fine in test tank so going to the BIG Pond tomorrow to see how LONG they last
PLACE YOUR BETS NOW 


http://www.hobbyking.com/hobbyking/store/__46161__HobbyKing_X_Car_45A_Brushed_Car_ESC_AUS_Warehouse_.html?strSearch=x%20car%20esc

[derekwarner]

oldshrimper.....not being a gambler ......& thinking of the criteria  and knowing you will have some very distracting biki clad adjudicator's to witness proceeding's ........
My guess is that the each ESC will outlast the battery capacity     or about 48 minutes each.....Derek

[old shrimper]

48 min is that all those lipo batt will run for ??     i will take my little charger but its pretty slow

[old shrimper]

well no magic smoke yet

[derekwarner]

Well.....based upon the delay in timing    it would appear that both ESC's  have exceeded a running time in excess of the battery capacity...
Would be very interested to hear the final run flat timing............   Derek

[old shrimper]

well as it was hot day and and a few people were swimming with kids and dogs 
we opted to leave after about 2 hrs of playing round
all so not being sure of the run time and reliability of the esc and only having ONE 2s 5000mAh lipo between us , and not knowing the distance range of the TX/RX units
as the wind was offshore if anything failed we stood the chance of loosing a boat 


you could hold the tip of your finger on the fins on the esc after about 20mins running time  (they were hot but not burn yourself  hot )
at the end of the session i put the multimeter on the batt and it read just under 8 v ( i was surprised )
 the esc is supposed to cut off if the battery gets to low or the esc gets to hot ?   if you program it correctly , we weren't sure about that bit
it has practice mode and professional mode, also not sure what that was about
any ideas ?


with 540/1 motor on 6.1 red turning a 55 mm 4B brass prop it needed 100% throttle setting on the TX  to get a good realistic bow and stern wave on B.Bs trawler
but the SkU 700 high torque motor  in the Tug on  direct drive turning a 60mm prop shop 4B prope in a steering nozzle only need 40% throttle to get a nice bow wave and  a deep trough in the center of the hull and a good stern wave ( at a 100% throttle setting it was joke as the hull was just climbing out of the water and burying the back deck under water
i was impressed with how much power it has in reserve even on 7.4 v HANDLES WELL TO FOR An AMSTERDAM
im going to give it run in the test tank tied  down to check the heat and batt life later on
i reckon the tug would tow a house brick of the beach on 100% throttle ON 12v the thrust it has is amazing
also going to put a small fan on the top of the esc and a heat sink with a fan on the motor in a few weeks when they get here
i think BB has some good shots of both boats motoring along he will put up
cheers Bob

[old shrimper]

this is a short vid of the run yesterday
link on photo bucket


http://s1266.photobucket.com/user/atomicmaloo/media/MODEL%20BOAT%20PIC/BobsTugVideo.mp4.html

[old shrimper]

ok here is an up date i ran the tug in the tank for 1;1/2 hours was at 50% throttle with a rubber band round the trigger on the TX and the tug was tied up to a statue with a bridal ,so it was on dead pull the whole time till the low battery setting on the esc cut in
 battery  ended up at 6.6v
the esc never got over 70c ( it has  90c cut off ) and the motor was at 55c  it was a 32c day in the sun
im going to but some cooling fans in . one on the motor and one on the esc and probably a big extractor fan in the stacks

[derekwarner]

OK OK......    1 & 1/2 hours was at 50% throttle  = ~~~~~ 45 minutes at 100% throttle ....in roundish calculation revision 
My bet was 48 minutes should you care to remember    & that was based on an ambient 30 degree C which was your area local temperature on 1st October
So to recalculate due to the temperature gradient [48 minutes divided by (32 * 30) = 45 minutes] which proves our OZ calculations to be 100% correct.......... ....Derek

[old shrimper]

i thought YOU was betting on how long the ESC would last that was the bets i was asking for ??
yer lipo battery is a bit slack at 45min at WOT    bit of a bummer if you had to change the batt mid pull in a tug towing comp

[derekwarner]

sorry oldsmrimper  ....please just read the words back......... "my guess is that the each ESC will outlast the battery capacity     or about 48 minutes each".....
In OZ, only Queenslanders change the rules 1/2 way thru a game.... 
BTW....what is my prize?    ..............Derek

[old shrimper]

    OK you win i was  to concerned about the esc blowing up to read it properly ( i guess its called OLD AGE )


so how do i put 2x mAh 5000 2s Lipo in series ?  do they work like OLD school batt the more cels you have the longer they last ?

[malcolmfrary]

Cells (and batteries) in series, the same AH but more volts therefore more current taken, therefore a shorter run time.
Batteries in parallel, same voltage, more AH stored, longer run time. 
Exactly like old school worked.
Series is original -ve line, +ve of that battery to -ve of the new, +ve of the new is your 14.8 volt supply for what is now a 4S 5000mAH battery.
Parallel is both -ve terminals connected together and both +ve terminals connected together to give a 2S 10000mAH battery.

[old shrimper]

thanks mate
so i need to make a harness up to conect them in parallel
the pos red to red on the second  batt and the neg black to black on second batt both mAh 5000  2s lipo 
, then from the + to ESC + first batt
and NEG on the first batt to NEG  on the esc will give a 1,000mAh
WRIGHT ?

this font sizing crap drives me up the wall

[malcolmfrary]

10,000 but yes, you have the idea. 
It is important with most batteries that they are at the same state of charge as near as possible when they get connected, because the one with more volts will try to charge the other up until they both have the same voltage.  When batteries that can deliver a huge current are involved, this can create problems both in the connecting wiring and sometimes in the batteries even with a small difference.  After connection, when they are settled, they keep the same voltage, no problem.
"Y" harnesses are available ready made.

[thunderchild]

Good Day All


Having a quick look through the problem and looking at the pictures, I don't know if I've got this right, but I've been led to believe that the fuse goes in-between the motors and the esc. That way if the motor is stalled for some reason, the fuse will blow before the esc does.

[Seaspray]

I have always put my fuses between the battery and esc. As it is usually in the instructions I think the motor uses excess current which is thru the ESC  which in turn is a higher than usual current from the battery. The fuse susses this out and blows. The only fuse I don't like is Quickblow. At time just turning the circuit on blows em 
Martin