speed controls for boats?

[Savage04]

i was on fine design r/c and i saw some hacker and astro flgiht speed controls and i was wondering what BEC stands for and what do the amps depend on like it sais 12-32 cells on 60 amps??? and will these work with brushless motors???


thanks

[TXTRCR]

BEC stands for Battery Eliminating Circuit, which means that if the controller has BEC then you do not need an reciever pack, but if it does not include a BEC then you must have a reciever pack to power the reciever or it will not work or smoke from the voltage of the batteries feeding into the receiver as recievers are not ment to run on more than 6 volts. the speed controllers with bec have seperate circuitry that runs power to the reciever. Im not sure on the amp ratings but i believe that is how many amps are delivered to the motor, or how many amps the speed controller will handle being drawn from the controller by the motor. Brushless controllers will only work on brushless motors. all the hacker controllers are brushless controllers but only a few of the astro flights are brushless. I think Chris Fine only sells the Brushed motor ESCs from Astro Flight. 208d, 207d, and 212d. I have had really good luck with the astro flight 207d controller, but it fails in comparison to the ESCs built by Andy at www.rc-hydros.com his controllers are the best there is for Brushed motors. Hacker seems to be the popular choice for brushless escs and motors in boats. I have no experience with brushless so i cant advise on those.

[Hydro Junkie]

You're right on the second try on the amperage rating. The amperage rating is the amount of amperage the ESC can control going to the motor. The higher the rating, the more amperage the ESC can handle without frying. Where the ESC gets tested is when you run at below wide open throttle. The ESC has to hold back the current to slow the motor to less than flat out. This generates heat, which is the destroyer of most electronics. That is why most boat manufacturers that are worth dealing with will sell water cooled ESC's. Water cooling is more efficient than air cooling, especially in a closed boat(MHO).

[TXTRCR]

so you dont like astro flights controllers then. mine has been ok but its nothing compared to andys controller that thing is a powerhouse. its got water cooling but doesnt need it at all even when driving at slower speeds.

[Climate]

The ESC has to hold back the current to slow the motor to less than flat out. This generates heat, which is the destroyer of most electronics.

Actually, current is determined by load on the motor, not by the ESC or batteries.
The reason current is higher at a slower speed is the motor is operating at an inefficient RPM, as well as the hull having more friction to overcome from it’s displacement in the water.

The three fundamental units in electricity are:
Voltage (V) volts
Current (I) amps
Resistance (r) ohms

A good way to think about electricity is to think of it like water pipes.
Voltage is equivalent to the water pressure.
Current is equivalent to the total flow rate.
Resistance is the size of the pipe (wire) it all runs through.


You want an ESC that is rated with a high enough current carrying capability so as to not heat up when it is under a high load such as ½ throttle running.
Water-cooling does not necessarily make an ESC better. It simply cools an ESC that gets hot from having a lot of current go through it.
If the ESC is of appropriate size, it should not get so hot as to require extra cooling.
There are a lot of great ESC’s made that do not have water-cooling.

Peter R.
www.climatemodels.com

[porschefan911]

Peter, y didnt u come to the race?

[DLM]

One item overlooked and that is the higher the amps go like 90 amps; the price tag jumps too which includes motor, bigger boat more cells , more up keep which always goes with it. Get equipment which will last in your budget category and if you don't the price triples in replacement area and you will be kicking your behind . Now if your are a high roller and got the jack, Radio Control Boat Modeller has an article about a rtr boat for ONLY $2495.95 and your worries will be over!! I like living inside in the winter!!!!

[Hydro Junkie]

Peter, I like your explanation. As I'm no expert on ESCs, I'm glad you were able to help on this one. Being a former Navy avionic tech, I know about the load to wattage curves, etc. I also know a majority of the electrics have no real air cooling, and we all know about electronics and heat. As many can't afford high dollar ESCs, I would still recommend the water cooling, even if this does sound like I'm limiting the options. After all, a cool circuit is a happy circuit :D

[TXTRCR]

my controllers of choice are, any of the Astro Flight models 212d, 208d, and 207d, any of RC-Hydros controllers all are excellent controllers, and some of the novak controllers EVX marine, EVX emaxx, and the Super Rooster. there are alot more, but these are the controllers that i have found work really well for 150 dollars or less.

[DLM]

The controllers you mention are fine for cars and etc but if they get damp or a few frops of water, say good-bye and the manufacturer will ask , did the get wet, of which they can see when they open them up, the moisture will tell the story! I had a Fusion and aTekin and it cost more to repair than replacement. It sounds like i know all the answers but been there, done that. End of story!

[DLM]

?, if you all know about heat and etc, why are you guys and gals here on this forum?People in the know like Peter and I are trying to help out but it is hitting deaf ears, so why do we frequent this site, to HELP OUT! Maybe we should bow out and let yo people make you're expensive mistakes and get RED faces!!