Ideas on Building a Reliable BL System by ReddyWatts.

[Steven Vaccaro]

Ok I told Reddy that I would post this in the "Tips & Info" Section of the site, but haven't had the time to do so. So we don't lose it on the old forum I'm going to post it here and stick it to the top for a while.

Ideas on Building a Reliable BL System by ReddyWatts.

I have written down some ideas for building a reliable, brushless boat from what I have learned from the OSE forum and experiences. Keep in mind; this has nothing to do with racing. It is for the novice that wants his new hobby project to be dependable.

1.Use no more than 8 inches of total wire between the batteries and the controller.

2. Use a .150 flex cable or larger on 12 cells or more. Use a .130 flex cable on 12 cells or less.

3. Use a 12XL to 14XL or larger motor with direct drive on catamaran, mono hulls 29 inches (1/8 scale) and above. Most hulls have a min/max recommendation for how many NiMH batteries it will handle.

4. Use a 6XL to 10XL and 12L to 14L series motors with direct drive on 28-inch to 22 inch (1/12 scale)or less hydro type, catamaran or mono hulls. These motors have a higher rpm/volt rating and use fewer batteries. This allows for high speeds with less weight and motor torque.

5.Use a 6S to 14S and 6L to 10L series motors with direct drive on 21-inch (1/16 scale) and smaller hydro type, catamaran or mono hulls. These motors have a higher rpm/volt rating and use 6-8 cells (S series) or 6-12 cells (L series).

6. Limit the loading of your controller to 60% amps and 75% voltage of its max ratings, 14 cells and above, due to current surges and boat weight.

7. Limit the loading of your controller to 70% amps and 75% voltage of its max ratings, 12 cells or less.

8. Design your boat to run with the “wide-open” amps at your motors "maximum" efficiency rating.

9. Install floatation in your hull, unless you are a certified scuba diver.

10. Grease and maintain your flex cable regularly, to keep it turning freely.

11. Make your flex cable metal tubing long enough to cover most of the flex cable, to prevent blowouts.

12. Use an ammeter to measure motor load. I suggest two different brands.

a. The "Watts Up" meter from Offshore Electrics. Look for it under, Tools.
It is a “peak recording”, ammeter for $50. It is very simple to use.

b. The Eagle Tree Micro "data logger" for $70 at Eagle Tree Systems. It will record your amps for the entire boat run and has add-ons for temp, display and rpm. It gives very detailed information and also works with a computer or an attached display.

www.eagletreesystems.com/.../micro.htm

13. Start amp testing with a small prop and move to larger ones until it is loaded to the motor maximum rating and not overloading your controller guideline. The larger your prop the higher your amps will go.

14. Use an infrared temperature meter to measure equipment maximum readings.

15. The maximum temperature reading for a controller is 150 F, the motor is 150 F and the batteries are 150 F. Always try to keep the controller and motor as far below these readings as possible with water-cooling, but the best way is lowering your amps.

16. Keep the receiver away from your battery wiring and run these wires perpendicular from each other if possible to minimize interference. Twisting receiver cables can also minimize interference.

17. Brushless controllers are more efficient when running them wide open.

18. Leave the controller "timing" option at factory default/low. It will not increase your speed by changing the setting, but will make the controller run hotter.

19. The first link below is to the FE Calc program. Download it to your computer for free. It is great for simulating a setup for your boat. Remember these guidelines when considering your maximum amps for your controller. This program does not calculate all of the variables, so start testing with a smaller prop than it calculates for your desired setup. You can add more equipment to the program if yours is not there, by adding it to the text file that comes with it.

Example: Use the second link below to get all of the Feigao motor information. Some are listed below.

www.rcboataholic.com/fe_calc.htm

img.diytrade.com/cdimg/85...223033.jpg

Feigao 540-12S 2958 2.1 .0136 B-Less 12 8 300g
Feigao 540-8S 4436 5.5 .0060 B-Less 8 8 300g
Feigao 540-9XL 1853 2.5 .0092 B-Less 9 16 372g
Feigao 540-10XL 1668 2.3 .0114 B-Less 10 16 372g
Feigao 540-12XL 1390 1.9 .0164 B-Less 12 16 372g
Feigao 540-14XL 1191 1.2 .0223 B-Less 14 16 372g

20. Using a transmission can soften current surges and make your setup more forgiving. You can load an 80-amp controller to 80% of its amp rating and 80% of its voltage rating. It makes for a very versatile setup, using different ratios. You can use any motor with a trans in a cat or mono hulls, but the trans also lowers your reliability. (Gears)

To use the FECALC for transmission setups, just divide the RPM/Volt value by your selected gear ratio;

Example: 10XL with an rpm rating of 1668 per volt and you are running a gear ratio of 1:33 to 1,(60-prop/45-motor), divide 1668 by 1.33 which gives you 1254 rpm, so if you look in the text file for a 10XL 1668 change the 1668 to 1254 and save." then reopen FECALC and "calculate".

21. Disconnect your middle wire (BEC) between the receiver and the controller, when using more than 12 cells.

22. Buy the controller last for your boat project. There is a sixty day replacement warranty from the date of purchase.

23 The balance point for a catamaran or mono hull is from (2/7) 28% to (1/3) 33% from the rear of the hull.

24. The balance point of a hydro type hull should be an inch or two behind the front sponsons


25. You can change the rotation of a brushless motor by swapping two of the three wires going to the motor.

These brushless motors are like 3 phase electric AC motors. The windings are connected in a "TRIANGLE". Picture the motor windings connected between each corner point. "A" on the top corner, "B" on the bottom right and "C" on the bottom left. The electric pulses out of the controller alternate pulsing to the motor wires in this order. a-b wires, b-c wires, c-a wires for each motor rotation. So if you swap "B" and "C" wires, it now reverses rotation around the triangle by going in this order. a-c, c-b and b-a. Therefore you cannot wire these motors up wrong, it only changes the direction of the rotation

26. Props are a critical item for your boat to perform as desired. There is a huge selection to choose from. This is a cheap option and usually the first step to make a stock boat run faster.

Carbon Fiber Props are light, sharp and don't need to be balanced or sharpened. They cost ½ the price of a Beryllium copper prop. They are great to use when testing your setup with many different props. They can flex under heavy load and shatter if they hit something.

Beryllium Copper props need be balanced, sharpened and can be polished. Great to use after you have selected a permanent prop for your setup. It will take about an hour to balance and sharpen one properly. You will need to purchase a prop balancer. I suggest the: “Top Flite Boat Prop Balancer”.
Do not inhale the filings or dust, it can make you ill. Be careful with contamination.

Aluminum props are fragile and flex under load. Unless you find a really good reason to use one (they don't need balancing isn't good enough) you should stay with BeCu (Octura) or bronze (Prather). Prather also sells a stainless steel prop.

Stainless props are much harder than beryllium and as a result it takes alot more sanding and working to sharpen, thin, balance and polish.


FORMULAS


To calculate run times

Battery Mah rating (times) 0.06 (divided by) motor load in amps = run time

Example: 3300 MAH (X) .06 (divided by) 35amps = 5.65 minutes of run time

To calculate your average amps

Battery Mah rating (times) 0.06 (divided by) run time = average motor load in amps

Example: 3300 Mah rating (times) 0.06 (divided by) 5.0 minutes = 39.6 amps

To calculate your geared RPM.

Motor shaft teeth (divided by) prop shaft teeth = multiplier.

12 motor shaft teeth (divided by) 24 prop shaft teeth = .5 multiplier

Motor RPM (times) .5 multiplier = geared prop RPM

To calculate your gear ratio.

prop shaft teeth count (divided) by motor shaft teeth count = gear ratio.

24 prop shaft teeth (divided by) 12 motor shaft teeth = 2/1 gear ratio

Meaning your motor turns (2) revolutions for each prop (1) revolution.

To calculate motor horse power

amps (X) volts (X) efficiency (divided by) 746 = horsepower.

Example: A 540 10XL was using 65 amps X 21.6 volts X .91 eff. / 746 = 1.7hp

I wrote this guideline, hoping it will help everyone to have a positive new experience with a brushless boat.

ReddyWatts

Updated 10/11/2006.

[MoparB]

Jesus. Well that certainly answers all of my questions!

[FE_Chris]

Thanks steve!

[quickwedge]

Thanks to Reddy + Steve!!.Great Info.I just bought 2 hulls from Scott @ Skunk Works and this info will be a great help guys !!

quick

[ReddyWatts]

Thanks Part Time and D. Smock, good info about props!

Different types of Octura props

12 are low lift ideal for submerged drive
X4 are medium lift general purpose props
M4 are like X4 but with the tongues removed to unload the prop
Y are like X series but have 10% more pitch
X5 are general all purpose med lift prop
X6 are higher lift than X4 and suitable for surface/semi surface use
14 are moderatley high lift for hydros and deep V's
16 are high lift props for riggers and hydro's
17 are the highest lift prop for riggers and outboards
P7 are similar to 17 series but more rake and less lifti
19 are high lift for riggers and hydro's
V9 are moderate lift suitable for riggers, hydros and SAW racing
20 are moderatley high lift suitable for riggers
21 are high lift for riggers and hydro's 22 are high lift surface drive only good straight line speed

[ReddyWatts]

Lehner, Feigao, Hacker, Nemesis, KB45, Ammo 2300 have 2 pole brushless rotors.

Neu, Plett have 4 pole rotors.

Mega, BK, 27SV, Blackjack-26 have 6 pole rotors.

MHZ/Shark has 8 pole rotors.

For a 2 pole motor rotor with 3 stationary outside stator coils, the controller will energize a stator coil 3 times in each rotor revolution.

For a 4 pole motor rotor with 3 stator coils, the controller will energize a stator coil 6 times in each revolution.

For a 6 pole motor rotor with 3 stator coils, the controller will energize a stator coil 9 times in each revolution.

2 pole energizes a stator coil every 120 degrees of rotation.
4 pole energizes every 60 degrees.
6 pole energizes every 40 degrees.

BL sensorless controllers use the feedback pulse from the wire not being used while it is energizing a stator coil to AUTOMATICALLY sync with the rotors of the different pole motors.

The more poles the motor has gives it more torque for pushing larger hulls, weight and props.

Increasing number of poles:
The number of motor poles can be increased to gain some improvement in motor torque. There are more conductors, resulting in more current that the rotor may accept. An increased number of poles will also produce a stronger magnetic field. For example, a 2-pole stator of 80-mm diameter and 90-mm length will output around 1.7 Nm torque; a 4-pole motor will output 2.3 N-m torque. A 6-pole motor in the same size would have about 2.8 N-m torque. While higher motor torque can be achieved by using a motor with a greater number of poles, this requires a higher output frequency to run at similar speeds.


A 4 or 6 pole motor is more forgiving than a 2 pole when accidently over propped. The current surges are not as high.

Some controllers can have problems running 4 or 6 pole motors. The Schulze and BK controllers have problems with the Neu Delta 4 pole motors. Hextronics and other brands of controllers with "out of date" revisions of software can have problems.

"Cogging" The controller does not stay in sync with the rotor at lower rpm's. The motor runs and sounds real ruff or can jump back and forth, but smooths out at higher rpms.

IMO, if a motor is not loaded properly for a controllers dynamic timing range, (to much or to little load) it will run hot.

Here is an explanation of running an ESC at half throttle from Castles site, given to us from Fast Guy.
"A speed controller controls power to the motor by turning full throttle current on and off really fast, 11 to 13 thousand times per second (Pulse Width Modulation or PWM). The percentage of each on/off pulse that is off compared to the part that is on determines how much power the motor sees. I.E. With a pulse that is 50% off and 50% on the motor will see 50% power*. Because each on pulse is 100% of full throttle current, a system set to pull 20 amps at full throttle through a Phoenix 10 will not last if you are throttled back to the point where you only see 10 amps on a wattmeter. The ESC in this case is still switching 20 amps, which it can’t do for long. Actually it is worse than the simple example above. Because an electric motor will always to try to pull as much power as is available to get to its rpm (volts times Kv), when you are running the motor below its Kv speed by switching power on an off, each on pulse will actually be way over the full throttle amp draw. That is why ESCs work harder at partial throttle than full throttle and why we underrate our ESCs. We underrate not so they can handle more current than their rating at full throttle, but so they can handle extended partial throttle operation with no problems."

[ReddyWatts]

Neu and Lehner offer brushless motors with wye or delta winding connections. I always wondered, "what is the difference in performance", so I will try to explain, what my simple mind could understand about it. Hope it helps.

The WYE motor winding is used in higher torque or higher voltage applications. Typically, DELTA motor winding is used in lower voltage or higher speed applications. A motor with windings in delta configuration gives low torque at low rpm, but can give higher top rpm. wye configuration gives high torque at low rpm, but not as high top rpm.

If you take a Wye winding motor (1000kv)and change it to a delta winding motor you will see it change to 1732kv. You will see a higher kv motor with less torque. Torque will be reduced by 43%. ("KV" is how many unloaded rpm the motor will run for each volt that is connected to it.)

Three phase motors come in two wiring patterns. It is called Delta because the three phases are hooked together in a triangle arrangement. Phase one uses terminals A & B. Phase two uses B & C. Phase three uses C & A. In electrical talk the phases are 120 degrees out of phase with each other. You could think of it as firing order in a multi cylinder gas engine. The Electronic Speed Control (ESC) first talks to or sends power to phase one. Then it waits 120 degree and sends power to phase two. And at 240 degrees it sends power to phase three. At 360 degrees (120 X 3) the whole process starts over again.

Y wind where each leg of the Y is a phase and the center of the Y is common. Y wind typically has higher winding resistance as two windings are in series for each phase. This is why some controllers have problems with delta motors. Delta gives a lower voltage feedback pulse to the controller.

The delta winding could be used in a a lighter, lower voltage. high rpm setup or a hydro that does not require a lot of torque. The more effecient wye winding works in all applications and is better for heavier mono or cat setups.

EXAMPLE of the same motor wired delta and wye.
NEU
1521/1.5y = 1050 rpm
1521/1.5d = 1850 rpm

1521/1.5Y will handle from 8-55 volts and is a 90%+ effecient motor with more torque. Max effeciency amps 50.

1521/1.5D will handle from 8-32 volts and is a 85%+ effecient motor with less torque. Max effeciency amps 90.

All rating calculations between the motors have a 1.732 relational value between a Wye and Delta connection.

Thanks to Skeeler for this information;
Neu motors are named DDLL, where DD is the stator diameter, and LL is the rotor length, both in tenths of an inch. For example,

1512 motor
Stator diameter: 1.5 in
Rotor length: 1.2 in

http://www.drcwebservices.com/ffe/neuspecs.htm

Wow, a pretty old thread! But looking at it again with two more years' experience I think the above is just a bit too simplified. To say that the WYE motor has more torque is not always true in the real world - in other words in an FE boat. An example would be two motors suited for 6S boats, the 1527/1.5D (1500 Kv) and the 1527/1Y (1250 Kv). In the same boat the DELTA motor appears to have a lot more torque, as the boat accelerates much harder than with the WYE wind. So in the same application, the D has the edge for raw power. The Y is a bit easier to drive as the power delivery seems more linear, due to the reduced torque.

To say that DELTA motors are for low voltage use is not quite accurate either. The 1527/3.5D (probably not available two years ago) has a Kv of 660 rpm, not very conducive to a low voltage setup.



The difference here is due to the Kv, not the wind type. The 1521 motor is rpm limited, and the theoretical rpm at max voltage for each is:

1521/1.5Y = 58,000 rpm
1521/1.5D = 61,000 rpm

The maximum motor speed (due most likely to the bearings used) is 60,000 rpm, and the voltages listed above are the closest to that limit.

Fluid; too little TIMING causes poor performance and excess heat. There is no "general rule" for timing advance, it depends entirely on the motor design and the amp load on the motor. I don't know where this idea of "0" timing advance came from, but it is very ill-advised for 2-pole motors.

The reason for timing advance is to allow enough time for the next coil to energize and build a magnetic field to attract the next advancing magnet. The more wire in the coil or the more amperage drawn, the more advance is required because it takes time to charge the coil. If there is too little timing advance, the coil will energize too late, hurting efficiency and building heat. Bottom line - too little or too much are both bad. You need to experiment to find the optimum for your setup....

I always ran my own turn 2-pole motors with between 10 and 15 degrees advance for oval racing applications where amp draw was 60-100 amps, and up to 25 degrees for SAW attempts drawing over 200 amps. I run 13-17 degrees with my 4-pole Neu "Y" winds pulling 140 amps, and 4 degrees with the "D" winds pulling 160 amps. My Scorpion 8-pole motor likes 15 degrees pulling 80 amps. Clearly there is no hard and fast rule for all motors.

About all I can say with certainty is that "0" degrees is almost always wrong

.

The Delta winding motor is less effecient.

Delta winding connection on left and Wye on the right.

[ED66677]

Great stuff ReddyWatts, I've reading it several times!!!
Have you ever thought about gears, just another little post to develop gears explanation, why to use gears...

[ReddyWatts]

Thanks Ed, I am no expert but try to share my ideas and hope it helps or sparks an idea.

Just get the right motor and forget the trans these days.

We now have the option to use a Neu or KB45 motor on a boat over 5 pounds with a single drive or over 10 pounds with dual direct drive, if your hull can handle the extra weight. KB45 or Neu motors do not need a trans.

If you are using a Fiegao motor single drive that weighs over 5 pounds or a Fiegao dual drive that weighs over 10 lbs. Add a trans to give it more torque.

You can get current surges that can fry your controller with these heavy boats when running in ruff water with a Fiegao or the CG/strut/prop is not setup correctly, when running the lower amp controllers. (We now have an option of some economy high amp controllers. This should not be as big of a problem as it was a few years a go.) The trans will soften these surges. These motors love high rpms with low torque, so take advantage of it. When running a dual drive your prop selection is very limited. An X430, X442, X447, X465, X470 and X665 are the only Octura left and right rotating props offered. A trans allows more flexibilty in loading your motor to these props, by changing gears. With a direct dual drive you may need to change the number of cells you are using to get the results you want or file down the props.

Remember a trans lowers your reliability. (Gears)

[ReddyWatts]

Example: 2s1p 25c 3300mah lipo

2s
1s is equal to one cell of 3.7 volts, so 2s is equal to 2 cells in series for 7.4 nominal volts, more when charged.

1p
Is how many cells are in parallel, so 2p would double the amp output for 2 packs in parallel.

25c is a multiplier for the "max amps rating".

25c (times)mah rating/1000 = max amps rating

25 (X) 3300 / 1000 = 82.5 max amps rating

then you take this and multiply it by how many cells series cells are in parallel (2p).

82.6 (X) 2p = 165 max amps rating.

You should only draw up to 80% of your battery max amps rating. You can damage a lipo battery, if you do not follow this rule.

Never run them completely down. Do not discharge them more than 70% of their MAH rating. Time your runs and use a Low Voltage cutoff. Set the Low Voltage cutoff at 3.3 - 3.4 volts.

Warm them to atleast 80F before using them to prevent premature failure.

Do not get them over 140F.

Charge/Discharge them to 60% when letting them sit on the shelf.

[ReddyWatts]

Diegoboy was thinking about the new members coming to the forum and how some of our conversations could get a little difficult to understand with all the abbreviations we use. Here are a few that came to mind.

Aft = Back of boat
AKA = Also Known As
BB = Ball Bearing
BEC = When using the ESC "Battery Eliminater Circuit" to power the receiver on the middle red wire coming from the esc instead of using an extra set of batteries
BL = Brushless
BTW = By the Way
BUMP = A text response to get the thread back to the top of a forum
CA = Cyanoacrylate Adhesive
CC = Castle Creations
CCW = Counter Clock Wise
CF = Carbon Fiber
CG = Center of Gravity (Also COG)
CNC = Computer Numerically Controlled
CW = Clock Wise
DR = Dual Rate (A switch on the transmitter to allow more or less servo travel)
ECM = Electronic Counter Measures
EPA = End Point Adjustment
ESC = Electric Speed Control
FG = Fiberglass
Freq = Frequency
FRP = Fiber Reinforced Plastic
FWIW = For What Its Worth
FS = For Sale
FYI = For Your Information
HOC = Hot Off the Charger
IIRC = If I Remember Correctly
IMO = In My Opinion
IRL = In Real Life
Kv = RPM (revolutions per minute) per volt - Kv (multiplied by) Voltage = RPM
LHS = Local Hobby Shop
LiPo, Li-Po, Li-Poly = Lithium Polymer (battery)
LSH = Limited Sport Hydro (hydroplane)
LSO = Limited Spec Offshore
LVC = Low Voltage Cutoff
mah = Milliamps per hour
Newbie, Newb = A new person or beginner
NIB = New In Box
NiMh = Nickel Metal Hydride (battery)
OP = Original Post (post # 1 in the thread)
PCM = Pulse Code Modulation
PPM = Pulse Position Modulation
Prop = Propeller
Prop Wash = The water movement created by a propeller
RFI = Radio Frequency Interference
RPM = Revolutions Per Minute
RTR = Ready To Run
Rx = Receiver
SAW = Straight-A-Way
SS = Stainless Steel
TBD = To Be Determined
TMI = Too Much Information
Tx = Transmitter
W/ = With
W/O = Without
WOT = Wide Open Throttle
WTB = Want To Buy
XTAL = Crystal

[ReddyWatts]

This is what I measured on the K&S brass tubing you can buy from OSE for the teflon tubing, but I usually pull the teflon and use (marine) grease to lubricate the flex cable installed directly in the brass tube with less spin friction. I clean and grease it after each days run.

The teflon is not consistant in size and can cause problems fitting correctly. Might need to sand it down or stretch it to size.

Teflon
.98 flex cable - 3/16" .014 - OD brass.
.130 flex cable -7/32" .014 - OD brass.
.150 flex cable -1/4" .014 - OD brass.
.187 flex cable - 9/32" .014 - OD brass.

No teflon tubing
.187 flex cable - 1/4 tubing

Thanks MM, I made the update.

[Mich. Maniac]

Reddy, just to save some from making my mistake could you post whether those sizes are actual K&S sticker sizes or I.D. sizes. I grapped some 1/4" K&S "sticker size" from LHS and it is too big even for .150 flex with teflon.

[ReddyWatts]

FeCalc is a computer program that is great for estimating which prop to start testing with for 2-pole motor setups.

Download the program here.
http://gallery.offshoreelectrics.com...?album=6&pos=6

http://www.offshoreelectrics.com/dow.../FEPackage.zip


You may download the attached text file into your fecalc program directory and replace the file there. This one has some of OSE's Fiegao, KB45 and Neu motors. Also the NeuEnegery lipo's 1P and 2P.

There are many variables in FE boating that keep this from being an exact science. These calculations are only ball park figures. Always start with a prop smaller than what you calculate for max amps and then work up to the larger prop as heat and amps allow.

Use the "Hydro / performance" setting when calculating a 4-pole Neu motor in a cat or mono hull. The amps will read too high if you dont by 20 -30%.

Updated FeCalc info file with the OSE motors.

FeCalc Text file data


.

[RCprince]

Reddy i'm doing some thing wrong here....I took the BJ motor with a 645 on 6s and I'm getting 69 (1.6 x 1.772 x 1606 x 22.2 x 0.000687 = 69)

[ReddyWatts]

1. Build a boat stand.
2. Drill and mount the strut and rudder. Might need to strengthen the transom.
3. Drill holes for water-cooling inlet and outlet.
4. Install radio antenna.
5. Install water jacket and thrust bearing on motor.
6. Place all equipment in boat to find the desired center of gravity. Move the motor around, so that you after you mount the motor, you will still be able to move the batteries and keep the COG in the desired range. 27-33%
7. Epoxy motor mount to hull. Might need to strengthen the inside bottom of hull.
8. Decide where to cut hole/slot for flex drive tube.
9. Decide where to drill hole for rudder/servo connecting rod.
10. Bend, then cut tubing to fit between strut and motor. Leave less than ½ inch gap between motor coupler and tube. Start with strut bottom 1/8 above the bottom of hull. Raise it during water tests to desired height. Use heat shrink on strut connection.
11. Cut flex cable to length needed.
12. Install flex cable and check alignment at motor and strut. One sweeping bend is better. Epoxy tube into hull.
13. Remove all parts.
14. Paint the hull.
15. Add floatation to hull and hatch.
16. Reinstall all parts and seal.
17. Mount servo and use rubber boot to waterproof connecting rod and hole.
18. Lubricate drive line.
19. Install radio and battery switch if used.
20. Install battery tie downs.
21. Install water-cooling hoses. Use cable ties on all connections. pressure test for leaks.
22. Test hull in bath tub for water leaks.
23. Program and test ESC.
24. Check motor rotation.
25. Check for receiver glitching.
26. Check everything for tightness, use blue thread lock on all threads.
27. Use tape to seal the hatch.

[ReddyWatts]

I hope by showing a structure of setups you will see the "Big Picture" for a better understanding of Fast Electrics.

There are to many variables for this data to fit all the different hull and motor loads. Many setups will fall outside this general information guideline.

FE SETUPS

--hull size /--------Cells---------/ ----Motor Kv----- / -------Prop Size------/---Type ESC---/-BEC-/ESC Amp Rating

17”- 24” / 2s LiPo or 6 cell NiMh / 5500 -3200Kv / 30mm - 40mm Diam. / Low Voltage / Avail. / 120 amp

20"-27" / 3s LiPo or 8 cell NiMh / 3500-2500kv / 35mm – 42mm Diam. / Low Voltage / Avail. / 120 amp

24”-29” / 4s LiPo or 12 cell NiMh /2650-1600Kv /37mm - 46mm Diam. / Low Voltage / Avail~Disc / 120-240 amp

26”-32" / 6s LiPo or 18 cell NiMh /1800-1100Kv /40mm - 52mm Diam. / Low or High / Disc. / 120-180-240 amp

30"- 36" / 8s LiPo or 24 cell NiMh / 1350-800Kv /45mm – 55mm Diam. / High Voltage / N/A / 180-240 amp

34" - 42" / 10s LiPo or 30 cell NiMh / 1100-600Kv /47mm + Diameter / High Voltage / N/A / 180-240 amp

38" - 46" / 12s LiPo or 36 cell NiMh / 900-550Kv / 50mm + Diameter / High Voltage / N/A / 240 amp

Always start testing with a small prop and work up to your desired amp readings!


HULL SIZE AND OSE MOTORS

This is a general guideline for the motors OSE sells. I know it is hard for this to cover all selections, since FE setups can be complex and extend over a wide range of extremes. Remember this is more for conservative setups to help new guys get started.

hull size…..... /…...... Neu….... /….. Feigao.540…../Feigao 580/...700SC../.SV27./.Proboat./..Ammo../.380.

<<"-20"....../.....1506........../.......Fiegao.S......./................./................./......../............../.............../.380 L

17”-24”…../….. 1506,1509./…..Feigao S-L…...../…............../................./......../............../................/........

20"-27"…../….. 1509,1512./…..Feigao L-XL...../….............../...700SC../.SV27./.Proboat./..Ammo../........

24”-29”…../…..1512,1515../…..Feigao XL…...../….............../...700SC../.SV27./.Proboat./..Ammo../.......

26”-32"…../.....1512,1515../…..Feigao XL….../….............../.,..700SC../.SV27./.ProBoat./............./........

30"-36"…../….. 1515,1521./…........…………..../….. 580L...../.............../........../.............../............./........

34"-42"…../….. 1521,1527. /…........………..…/….. 580L...../................/........./................/............./........

38"-46"…../…..1527,2215. /….. ......……..……/................../................./........./................/............./........

40"-60"..../.......2230......./Little Screamer 63mm outrunner/

MOTOR MAXIMUM WATT RATINGS.

Always look at the maximum WATTS the motor is rated to handle. The heat will kill the magnets and possibly the controller if you get it to HOT.

Continuous rating/ 30 second rating

Neu -
1506 - 700 watts/ 1500 watts
1509 - 1000 watts/ 2000 watts
1512 - 1200 watts/ 2500 watts
1515 - 1500 watts/ 2700 watts
1521 - 1700 watts/ 3000 watts
1527 - 2100 watts/ 3300 watts
2215 - 3000 watts/ 5000 watts
2230 - 6000 watts/ 10000 watts

Feigao
580L - 1800 watts/
540 XL - 800 watts/ 1600 watts
540L - 600 watts/ 1300 watts
540S - 450 watts/ 1000 watts
380L - 450 watts/ 1000 watts

SV - BlackJack 800 watts/ 1400 watts

Ammo 2300 - 700 watts/ 1400 watts

700sc - 650 watts

Volts (X) Amps = Watts

Always calculate your setup Watts and prop it to run close to your motors Max Amp rating. (maximum effeciency rating)

Example:
Specs for the motor in the BJ
TURNIGY brushless Inrunner

Power: 460W
Battery Config: 3-5S

Watts / Volts = maximum AMPS to keep motor cool - recommended by manufacturer.

460 watts / 11.1volts = 41.4 amps max

460 watts / 14.8 volts = 31 amps max

460 watts / 18.5 volts = 25 amps max


FeCalc can get you in the ballpark for loaded 2-pole motor watts and amps. It is just an estimate, but can give you a good idea of which prop to start testing with.

The Feigao 540 motor max amps ratings are attached below.




__________________

[ReddyWatts]

""I see that most jackets have the inlet and outlet only 90 degrees apart, and they are usually mounted with the inlet at least 45 degrees below the top. What this does is create an airlock that prevents water form getting to the top of the motor - arguably the hottest part. The UL-1 jacket as it comes on the boat is worse with both inlet and outlet side-by-side - with this configuration the top half of the motor doesn't even get water. At least mount the outlet as high as possible, meaning the top front of the motor.

Info provided by Fluid.""

Why take a chance of getting air pockets in the motor cooling jacket during a run? Place the water outlet at the top/front on the motor and let the air escape easily.

Let the water flow freely through the system. Fast flowing water, turbulence and with more temperature differential results in better cooling.

[Punisher 67]

Steven and Reddy as much usefull info as you have here for me nothing speaks as much volumes as a well placed thought out boat setup picture , before I engage any build I research many examples of that build and assess all angles and every aspect of that setup with as many examples as possible . I am a firm advocate of as many build setup pictures as one can take . for me the bulk of my learning has been through pictures , pictures of failed setups are every bit as usefull as pictures of winning setups , weather you build is a success or failure the info you supply is equally important

[ReddyWatts]

These are great tools for a better understanding of FE setup connections.

System Wiring Illustrator


Lipo Connection Illustrator




.

[exotica]

...what a great thread!

[ReddyWatts]

Thought this might help when looking for the next prop to try. I listed some Octura props with increasing pitch. This may show why going to a smaller diameter prop with more pitch or more blades can be faster. More blades means less slippage under heavier load, can be more effecient.

PROP Pitch/inches

X437/3-- 2.072
X438---- 2.100
X440---- 2.198
X440/3-- 2.198
Y536---- 2.200
Y537/3-- 2.279
X442---- 2.310
X637---- 2.368
X445---- 2.478
X640---- 2.512
X447---- 2.590
X447/3-- 2.590
X642---- 2.640
M545---- 2.655
X448---- 2.660
X450---- 2.758
X450/3-- 2.758
X645---- 2.832
Y547---- 2.849
X548---- 2.850
X452---- 2.870
X452/3-- 2.870
X646---- 2.896
X646/3-- 2.896
X455---- 3.038
X455/3-- 3.038
X648---- 3.040
X457---- 3.136
X457/3-- 3.136
M650---- 3.190
X460---- 3.304
Y557---- 3.449
X560---- 3.540

X427---- 1.498 0.125
X430---- 1.652
X431---- 1.708
X432---- 1.764
Y531---- 1.877
X435---- 1.932
X632---- 2.016
Y534---- 2.059
Y535---- 2.125

[ReddyWatts]

Waveform of a Brushless Motor ESC.

This video shows how an ESC uses a PWM waveform to control motor speed. It simulates an AC sine wave using positive and negative DC pulses. Notice how it changes the DC pulse widths but keeps a constant peak voltage during the complete throttle range. The peak voltage remains at your battery pack voltage.



Why it is best to run at full throttle.
A speed controller controls power to the motor by turning full throttle current on and off really fast, 11 to 13 thousand times per second (Pulse Width Modulation or PWM). The percentage of each on/off pulse that is off compared to the part that is on determines how much power the motor sees. I.E. With a pulse that is 50% off and 50% on the motor will see 50% power*. Because each on pulse is 100% of full throttle current, a system set to pull 20 amps at full throttle through a Phoenix 10 will not last if you are throttled back to the point where you only see 10 amps on a wattmeter. The ESC in this case is still switching 20 amps, which it can’t do for long. Because an electric motor will always to try to pull as much power as is available to get to its rpm (volts times Kv), when you are running the motor below its Kv speed by switching power on an off, each on pulse will actually be way over the full throttle amp draw. That is why ESCs work harder at partial throttle than full throttle and why we underrate our ESCs. We underrate not so they can handle more current than their rating at full throttle, but so they can handle extended partial throttle operation with no problems. CC

An amp is measured by how many electrons pass a point on a wire in one second. The narrower pulse current that is used by the ESC output during half throttle will have a higher peak current but read less on the input ammeter because it is seeing less passing electrons for the same period of time as it would at full throttle using wider pulses. This is why you dont see the high amps on the input side

m4a1user; What happens at low throttle is that the FET goes into the linear mode for a larger percentage of the on-time. That means the FET spends more time heating than it should - and hot FETs have more resistance, meaning next time they are in linear mode, they will heat up even hotter. At the same time, the motor is at lower RPM and therefore pulling more amps (a stalled motor will draw the maximum current).

You can get a lower RPM (ie, a lower average voltage) at maximum duty cycle only by lowering the input voltage. The speed control will run better with a lower input voltage even though it may be passing more amps simply because there will be less time for the FETs to be in linear mode. It is not an exaggeration to say that the FET may have 10X or more resistance when in linear mode. Heat generated is directly related to resistance.

Thank you Andy Kunz for very simply explaining this phenom to me so I can share this with fellow RC'ers

I hope this helps to clarify what PWM means and why it is better to run it wide open, than half throttle. The peak amps and esc resistance in the esc go up causing more heat at half throttle. Less work, stress and heat on the FETS running at WOT.

[ReddyWatts]

Posted by Detox

[ReddyWatts]

Handy chart posted by Ray R

FractionDecimalChart[1].pdf

[HydroMike]

Cool alot of nice info thanks alot

[mxrb18]

I hope by showing a structure of setups you will see the "Big Picture" for a better understanding of Fast Electrics.

There are to many variables for this data to fit all the different hull and motor loads. Many setups will fall outside this general information guideline.

FE SETUPS

--hull size /--------Cells---------/ ----Motor Kv----- / -------Prop Size------/---Type ESC---/-BEC-/ESC Amp Rating

17”- 24” / 2s LiPo or 6 cell NiMh / 5500 -3200Kv / 30mm - 40mm Diam. / Low Voltage / Avail. / 120 amp

20"-27" / 3s LiPo or 8 cell NiMh / 3500-2500kv / 35mm – 42mm Diam. / Low Voltage / Avail. / 120 amp

24”-29” / 4s LiPo or 12 cell NiMh /2650-1600Kv /37mm - 46mm Diam. / Low Voltage / Avail~Disc / 120-240 amp

26”-32" / 6s LiPo or 18 cell NiMh /1800-1100Kv /40mm - 52mm Diam. / Low or High / Disc. / 120-180-240 amp

30"- 36" / 8s LiPo or 24 cell NiMh / 1350-800Kv /45mm – 55mm Diam. / High Voltage / N/A / 180-240 amp

34" - 42" / 10s LiPo or 30 cell NiMh / 1100-600Kv /47mm + Diameter / High Voltage / N/A / 180-240 amp

38" - 46" / 12s LiPo or 36 cell NiMh / 900-550Kv / 50mm + Diameter / High Voltage / N/A / 240 amp

Always start testing with a small prop and work up to your desired amp readings!


HULL SIZE AND OSE MOTORS

This is a general guideline for the motors OSE sells. I know it is hard for this to cover all selections, since FE setups can be complex and extend over a wide range of extremes. Remember this is more for conservative setups to help new guys get started.

hull size…..... /…...... Neu….... /….. Feigao.540…../Feigao 580/...700SC../.SV27./.Proboat./..Ammo../.380.

<<"-20"....../.....1506........../.......Fiegao.S......./................./................./......../............../.............../.380 L

17”-24”…../….. 1506,1509./…..Feigao S-L…...../…............../................./......../............../................/........

20"-27"…../….. 1509,1512./…..Feigao L-XL...../….............../...700SC../.SV27./.Proboat./..Ammo../........

24”-29”…../…..1512,1515../…..Feigao XL…...../….............../...700SC../.SV27./.Proboat./..Ammo../.......

26”-32"…../.....1512,1515../…..Feigao XL….../….............../.,..700SC../.SV27./.ProBoat./............./........

30"-36"…../….. 1515,1521./…........…………..../….. 580L...../.............../........../.............../............./........

34"-42"…../….. 1521,1527. /…........………..…/….. 580L...../................/........./................/............./........

38"-46"…../…..1527,2215. /….. ......……..……/................../................./........./................/............./........

40"-60"..../.......2230......./Little Screamer 63mm outrunner/

MOTOR MAXIMUM WATT RATINGS.

Always look at the maximum WATTS the motor is rated to handle. The heat will kill the magnets and possibly the controller if you get it to HOT.

Continuous rating/ 30 second rating

Neu -
1506 - 700 watts/ 1500 watts
1509 - 1000 watts/ 2000 watts
1512 - 1200 watts/ 2500 watts
1515 - 1500 watts/ 2700 watts
1521 - 1700 watts/ 3000 watts
1527 - 2100 watts/ 3300 watts
2215 - 3000 watts/ 5000 watts
2230 - 6000 watts/ 10000 watts

Feigao
580L - 1800 watts/
540 XL - 800 watts/ 1600 watts
540L - 600 watts/ 1300 watts
540S - 450 watts/ 1000 watts
380L - 450 watts/ 1000 watts

SV - BlackJack 800 watts/ 1400 watts

Ammo 2300 - 700 watts/ 1400 watts

700sc - 650 watts

Volts (X) Amps = Watts

Always calculate your setup Watts and prop it to run close to your motors Max Amp rating. (maximum effeciency rating)

Example:
Specs for the motor in the BJ
TURNIGY brushless Inrunner

Power: 460W
Battery Config: 3-5S

Watts / Volts = maximum AMPS to keep motor cool - recommended by manufacturer.

460 watts / 11.1volts = 41.4 amps max

460 watts / 14.8 volts = 31 amps max

460 watts / 18.5 volts = 25 amps max


FeCalc can get you in the ballpark for loaded 2-pole motor watts and amps. It is just an estimate, but can give you a good idea of which prop to start testing with.

The Feigao 540 motor max amps ratings are attached below.




__________________

Do you have any idea what a suitable setup would be for a 72" CRC5000 Cat? I was considering a dual 12S setup with Tp-5680 (600kV 5Y, 800kV 4Y, or 1070kV 3Y) motors, twin ZTW Seal 300A Esc's, and 4 6S 5000maH 70C batteries (12S per motor). Any info would be awesome. I just need to determine the right motor setup to get on plane well but still achieve really good top end speed. Thank you