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Old 05-01-2011, 09:24 PM   #1
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Default Programming ESC's

When programming an ESC, is it best to use a lower S count battery? I read somewhere that if one plugs their 6S battery into the ESC when programming, the ESC will overheat. I have a couple of new 125 AMP ESC's that are not supported by a programming card, so I must program them using my transmitter - this could take a while I am guessing, and I don't want to fry the ESC's.

When programming the cell count, if I am using say a 3S battery for programming, but will ultimately use 6S to actually fly the model, I assume I should program it for 6S - is this correct?

Thanks for any expert insight.
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Old 05-02-2011, 12:01 AM   #2
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I haven't heard of this, but it shouldnt, the ESC regulates amperage flow it doesn't draw amps, except for the miniscule amount it may need to do it's own job. The motor and the RX draws the amps. If they aren't doing anything then the amps simply won't be drawn. The battery won't force any more amps that the devices connected to them are asking for. Unless you go crazy with the voltage (translation: don't plug it into the wall socket ).

As far as what or how you should program it, I think that probably depends on the make/model of the ESC.

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Old 05-02-2011, 07:48 AM   #3
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And usually the cell count will auto set itself when ESC detects the pack connected to it.

Sounds a bit strange ... use lower power to program than what is going to be powering model ? In my opinion if ESC cannot take the power pack intended during programming - then ESC in my view is not suitable for m,y model.

Is this something you have heard from another modeller or read somewhere ? I'm interested if it was read - so to check exactly what they say .. there might be something to learn from it ...

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Old 05-02-2011, 01:33 PM   #4
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Originally Posted by solentlife View Post
Is this something you have heard from another modeller or read somewhere ? I'm interested if it was read - so to check exactly what they say .. there might be something to learn from it ...
I read it in the review/discussion section on Hobby King under the Turnigy Plush 80 ESC item. There are a ton of review discussions to read through, so it may be a pain in the arse to find it again.

Even as a neophite electric hobbyist, it sounded strange to me, too.

By the way - I ended up ordering a pair of those ESC's to use with a pair of Cyclone Power 2800kv motors I'm using in the Mig-29 I'm building. I also bought the programming card. Everything went fine in the programming phase, but once I briefly ran up the motors to test the system, one of the ESC's fried.
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Old 05-02-2011, 03:23 PM   #5
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Your best bet is to figure the maximum amp draw you expect to see in actual use, then get an ESC that can handle 1 1/2 times that. This gives you a safety net.

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Old 05-02-2011, 04:26 PM   #6
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Most motors will give a recc'd ESC to use with it ... and I regard that as a minimum rated ESC. Next rated step up is my usual solution.

Problem with many online adverts I read for ESC's ... same with Lipo's ... the ratings are often overquoted ... it's not unusual for an ESC to say eg 30A ... then when you check deeper into it's specs it's actually a 25A continuous max or lower.

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Old 05-02-2011, 05:20 PM   #7
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Originally Posted by solentlife View Post
Most motors will give a recc'd ESC to use with it ... and I regard that as a minimum rated ESC. Next rated step up is my usual solution.

Problem with many online adverts I read for ESC's ... same with Lipo's ... the ratings are often overquoted ... it's not unusual for an ESC to say eg 30A ... then when you check deeper into it's specs it's actually a 25A continuous max or lower.

Subsequently, I have returned the Plush 80 ESC for a warranty exchange, but also purchased a new pair of 125 AMP ESC's. The Cyclone Power 2800kv motors carry an advertised rating of 69 AMP draw at a maximum 1500 watts on 6s Lipo's, which is what I am running. As a newbie, it's hard to know what is a manufacturing fault/fluke or what is actually underspec for a particular application. Several modelers told me that the Plush 80 ESC's would be plenty for the CP motors, but like I said, it's hard to sort out fact from fiction. This electric power situation is a little daunting to learn.
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Old 05-02-2011, 05:29 PM   #8
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Originally Posted by solentlife View Post
Most motors will give a recc'd ESC to use with it ... and I regard that as a minimum rated ESC. Next rated step up is my usual solution.

Problem with many online adverts I read for ESC's ... same with Lipo's ... the ratings are often overquoted ... it's not unusual for an ESC to say eg 30A ... then when you check deeper into it's specs it's actually a 25A continuous max or lower.
Nice thing about the Castle Creations ESC's. I've actually run them at their rated maximum currents without problems or concerns.

But you can NEVER run them (or any ESC) at over their maximum VOLTAGE rating!

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Old 05-02-2011, 05:29 PM   #9
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69A on a 6S pack would give 1531 watts nominal ... that is not max from a pack like that... with losses ... higher voltage from charged state ... the ESC would be subjected to significantly higher.

I'll let others expand on it that know far more than I ... but that's my take on the situation ...

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Old 05-02-2011, 05:50 PM   #10
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Originally Posted by solentlife View Post
69A on a 6S pack would give 1531 watts nominal ... that is not max from a pack like that... with losses ... higher voltage from charged state ... the ESC would be subjected to significantly higher.

I'll let others expand on it that know far more than I ... but that's my take on the situation ...
What is the formula for calculating watts? How does the motor play into the calculation, or is it calculated on the battery pack only? I suppose that knowing the appropriate formulas and how to apply them is a big part of what I am lacking as a newbie. Also, I don't yet own any proper testing devices, so any advice what I should acquire and where to read up on the subject will be greatly appreciated.
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Old 05-02-2011, 06:27 PM   #11
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Originally Posted by daddyrabbit1954 View Post
What is the formula for calculating watts? How does the motor play into the calculation, or is it calculated on the battery pack only? I suppose that knowing the appropriate formulas and how to apply them is a big part of what I am lacking as a newbie. Also, I don't yet own any proper testing devices, so any advice what I should acquire and where to read up on the subject will be greatly appreciated.

The formula for watts is voltage times amperes. So if you've got a motor pulling 45 Amps at 15 volts, that's 675 watts.

If you're looking at continuing on electric models, one of the things you should consider is buying a wattmeter, such as the Astroflight Whattmeter. The money it costs will pay for itself in protecting your motors/esc/batteries from severe overload from the wrong propeller.

Electric motors are dumb. They will happily turn any prop you put on them with little outside indication. Until smoke pours out of the motor. Or ESC. Or battery.

These motors pull a minimum current with no prop attached, referred to as the no load current. The maximum current they pull is determined by the propeller selected. The bigger the prop, the higher the current. That is, until smoke pours out.

So, those wattmeters will show you exactly how your setup is running, and will let you know if the motor/esc/battery setup is safe.

As for calculating all this stuff, check out those computer programs that do it all for you, such as www.motocalc.com, free for 30 days, then $39.00.

My thread below has a little info on this subject:
Thread on 70 size glow engine conversion to electric
http://www.wattflyer.com/forums/showthread.php?t=45222

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Old 05-02-2011, 07:24 PM   #12
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It is also worth considering one of the new Turnigy Super Brain series of ESC from Hobby King. They are programmed from your computer via USB. They also have data logging so that you can keep a true record of throttle position, amp draw, ESC temp, battery voltage and motor RPM throughout your entire flight.

These ESCs go for about a $10.00 premium plus $8.00 (approx) for the USB interface. But they replace well over $100 worth of test equipment to obtain all the same data. Best investment I ever made. I've never read a post on any board from anyone else using these Super Brain ESCs so they must be fairly new. I love mine!
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Old 05-02-2011, 09:08 PM   #13
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Originally Posted by Rockin Robbins View Post
It is also worth considering one of the new Turnigy Super Brain series of ESC from Hobby King. They are programmed from your computer via USB. They also have data logging so that you can keep a true record of throttle position, amp draw, ESC temp, battery voltage and motor RPM throughout your entire flight.

These ESCs go for about a $10.00 premium plus $8.00 (approx) for the USB interface. But they replace well over $100 worth of test equipment to obtain all the same data. Best investment I ever made. I've never read a post on any board from anyone else using these Super Brain ESCs so they must be fairly new. I love mine!
Thanks for the heads-up on the super-brain ESC. I will order one or two next time I place an order with them.
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Old 05-02-2011, 09:10 PM   #14
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Originally Posted by Rockin Robbins View Post
It is also worth considering one of the new Turnigy Super Brain series of ESC from Hobby King. They are programmed from your computer via USB. They also have data logging so that you can keep a true record of throttle position, amp draw, ESC temp, battery voltage and motor RPM throughout your entire flight.
Good point.

For those who want ESC's built in the USA "With USA and foreign parts", check out the Castle Creations ICE series of Electronic Speed Controls.

I've got a CC 80 Amp HV ICE ESC. This thing records Volts, Battery ripple volts, current, ampere hours, watts, temperature, RPM, throttle input in milliseconds (0.5 to 2.5 ms) and power in percentage of 100%.

It can be programmed to sample these parameters from something like 10 readings per second to seconds between readings. A reading once per second will give a little over an hour of flight data. Output is a graph program by CC. The raw data is on a standard Excel spreadsheet.

Very nice.

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Old 05-03-2011, 05:48 PM   #15
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Originally Posted by kyleservicetech View Post
Good point.

For those who want ESC's built in the USA "With USA and foreign parts", check out the Castle Creations ICE series of Electronic Speed Controls.

I've got a CC 80 Amp HV ICE ESC. This thing records Volts, Battery ripple volts, current, ampere hours, watts, temperature, RPM, throttle input in milliseconds (0.5 to 2.5 ms) and power in percentage of 100%.

It can be programmed to sample these parameters from something like 10 readings per second to seconds between readings. A reading once per second will give a little over an hour of flight data. Output is a graph program by CC. The raw data is on a standard Excel spreadsheet.

Very nice.
I see that a vendor on Amazon has the CC Ice 100 AMP ESC for $100 - not too bad a price for an American made product. Are support/warranty issues covered directly by Castle Creations or do they need to go through the vendor?
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Old 05-03-2011, 06:07 PM   #16
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Originally Posted by daddyrabbit1954 View Post
I see that a vendor on Amazon has the CC Ice 100 AMP ESC for $100 - not too bad a price for an American made product. Are support/warranty issues covered directly by Castle Creations or do they need to go through the vendor?
Good question. As far as I can tell though, Amazon is no different than buying it through the local hobby shop, where I bought mine. And the one time I had a problem with one of my CC ESC's several years ago, all CC wanted is a copy of the receipt.

If you have room for it, got for the standard ICE 100 Amp ESC, not the ICE "Lite". IMHO, those heat sinks on the standard ESC make it a little more robust. And the standard and Lite units are the same price.

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Old 05-03-2011, 06:41 PM   #17
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Originally Posted by kyleservicetech View Post
Good question. As far as I can tell though, Amazon is no different than buying it through the local hobby shop, where I bought mine. And the one time I had a problem with one of my CC ESC's several years ago, all CC wanted is a copy of the receipt.

If you have room for it, got for the standard ICE 100 Amp ESC, not the ICE "Lite". IMHO, those heat sinks on the standard ESC make it a little more robust. And the standard and Lite units are the same price.
One more question - I found this question via an internet search, but there was no answer: "I just purchased a Castle Creations Phoenix Ice 100 amps to be used on my 600 Heli and I came across a little issue.The Esc has a built in Bec and I would like to eliminate it so I could use the align external bec for a lot of different reasons, however when I disconected the red wire of the esc I was not able to link it up to the computer thru the castle link. I watched some videos of people setting their Esc but nobody metions any issues like Im having. I was just wondering if anyone could give me some advice on this issue as I would really like to use the esc the proper way and be able to use my own bec."

I will be using the ESC the same way this user was attempting to use it - running a separate UBEC. Have you (or anyone else) run into this issue? If so, how did you solve it? Not much point in buying the advanced monitoring capability built into the unit if I won't be able to use it.
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Old 05-03-2011, 09:59 PM   #18
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Holy cow! That thing has a 5 amp BEC! What would you buy to do better? Seems darned safe to me.

What would a UBEC do better? Enquiring minds want to know! Also I wonder what not using the BEC would do with not collecting the information. That 's really interesting...

Could you not put a switch on the red wire, leaving it off in flight but turning it on for USB interface?

Also note that even at the $100 price of new American technology the price is very well justified by the amount of test equipment it replaces! Those Castle Ice units look bulletproof! I wouldn't doubt that as competitors enter the business of data logging ESCs and production costs come down we'll expect data logging for little or no increase in price soon. Progress is great!
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Old 05-03-2011, 11:05 PM   #19
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Originally Posted by Rockin Robbins View Post
Holy cow! That thing has a 5 amp BEC! What would you buy to do better? Seems darned safe to me.

What would a UBEC do better? Enquiring minds want to know! Also I wonder what not using the BEC would do with not collecting the information. That 's really interesting...

Could you not put a switch on the red wire, leaving it off in flight but turning it on for USB interface?

Also note that even at the $100 price of new American technology the price is very well justified by the amount of test equipment it replaces! Those Castle Ice units look bulletproof! I wouldn't doubt that as competitors enter the business of data logging ESCs and production costs come down we'll expect data logging for little or no increase in price soon. Progress is great!
The model that I am building uses 11 servos for flight controls and has three non-servo electric retracts. I've been told that a separate BEC at something higher than 5 AMPS is necessary for the load the servos will pull. In addition, the advice has been to run a separate BEC and battery for anything that uses 4s and up flight batteries. My model uses 6s and the motors pull a lot of amps. To not run a separate esc runs the risk of losing power to flight controls as the two motors/fans quickly draw down the flight batteries.

I don't know if a switch would do the trick as I don't yet own a CC Ice ESC.
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Old 05-04-2011, 12:39 AM   #20
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Originally Posted by daddyrabbit1954 View Post
The model that I am building uses 11 servos for flight controls and has three non-servo electric retracts. I've been told that a separate BEC at something higher than 5 AMPS is necessary for the load the servos will pull. In addition, the advice has been to run a separate BEC and battery for anything that uses 4s and up flight batteries. My model uses 6s and the motors pull a lot of amps. To not run a separate esc runs the risk of losing power to flight controls as the two motors/fans quickly draw down the flight batteries.

I don't know if a switch would do the trick as I don't yet own a CC Ice ESC.
With a model with 11 servos, IMHO, you definitely need primary and backup power to your receiver and servos.

What I did on my 7 Hitec 645MG servo'd model was use a Castle Creations 10 Amp Switching BEC on the receiver's battery input. That CC BEC was programmed to 6.6 Volts DC.

And, as a backup, a two cell 2300 Mah A123 battery pack, with two series 9 ampere silicon diodes in series in the battery packs red wire. This drops the voltage of the A123 pack to less than the 6.6 VDC programmed into the CC BEC. As a result, the A123 cells are just "Floating", unless the Castle Creations BEC looses voltage due to an overload. (These switching BEC's generally just lower their voltage when overloaded, with no damage to them)

After a days worth of flying, the A123 pack was topped off with a Cellpro Powerlab 8 charger. Only about 20 milliampere hours was required to top the A123's off, so that indicates the CC BEC was handling most of the load. If you go this route, just make one flight, then top off the A123 battery. If it takes more than perhaps 500 mah or 1000 mah, you may need to go to the Castle Creations 20 Ampere BEC, or just go with the 20 Amp unit right away.

And, you do not need to worry about loading down the A123 cells, they will put out 40 amperes without issue, enough to melt your servo wires. (I accidentally shorted the servo sized battery leads on a two cell 2300 Mah A123 pack. Burned the copper wires right out of the insulation of the wires. Didn't harm the battery, at all, I could swear that battery was laughing at me.)

The A123 pack was plugged into a battery switch, that connects to an unused channel on my receiver, as a dual battery input to the receiver.

Since the A123 pack weighs in at about 4 1/2 ounces, that provides a little extra security at a reasonable weight.

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Old 05-05-2011, 04:43 AM   #21
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Originally Posted by kyleservicetech View Post
With a model with 11 servos, IMHO, you definitely need primary and backup power to your receiver and servos.

What I did on my 7 Hitec 645MG servo'd model was use a Castle Creations 10 Amp Switching BEC on the receiver's battery input. That CC BEC was programmed to 6.6 Volts DC.

And, as a backup, a two cell 2300 Mah A123 battery pack, with two series 9 ampere silicon diodes in series in the battery packs red wire. This drops the voltage of the A123 pack to less than the 6.6 VDC programmed into the CC BEC. As a result, the A123 cells are just "Floating", unless the Castle Creations BEC looses voltage due to an overload. (These switching BEC's generally just lower their voltage when overloaded, with no damage to them)

After a days worth of flying, the A123 pack was topped off with a Cellpro Powerlab 8 charger. Only about 20 milliampere hours was required to top the A123's off, so that indicates the CC BEC was handling most of the load. If you go this route, just make one flight, then top off the A123 battery. If it takes more than perhaps 500 mah or 1000 mah, you may need to go to the Castle Creations 20 Ampere BEC, or just go with the 20 Amp unit right away.

And, you do not need to worry about loading down the A123 cells, they will put out 40 amperes without issue, enough to melt your servo wires. (I accidentally shorted the servo sized battery leads on a two cell 2300 Mah A123 pack. Burned the copper wires right out of the insulation of the wires. Didn't harm the battery, at all, I could swear that battery was laughing at me.)

The A123 pack was plugged into a battery switch, that connects to an unused channel on my receiver, as a dual battery input to the receiver.

Since the A123 pack weighs in at about 4 1/2 ounces, that provides a little extra security at a reasonable weight.
Dennis

Until you mentioned them in your post, I had never heard about A123 batteries. I did some research and from what I can tell, you are talking about using two 2300 Mah A123 cells? I found these:
http://www.dealextreme.com/p/trustfire-protected-18650-lithium-battery-2400mah-2-pack-gray-5776

Would these be suitable? Don't know for sure if these are considered as A123 cells.
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Old 05-05-2011, 05:12 AM   #22
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Originally Posted by daddyrabbit1954 View Post
Dennis

Until you mentioned them in your post, I had never heard about A123 batteries. I did some research and from what I can tell, you are talking about using two 2300 Mah A123 cells? I found these:
http://www.dealextreme.com/p/trustfire-protected-18650-lithium-battery-2400mah-2-pack-gray-5776
Would these be suitable? Don't know for sure if these are considered as A123 cells.
I'm not certain what those cells are, that size cell is generally 1000 mah, not 2300 mah.

Take a look at one place that sells A123 receiver packs. If you're radio will handle a 5 cell nih pack, the 2 cell 2300 Mah A123 battery is a direct drop in, no regulator is required. Depending on the size of your model you might consider the 2S2P pack from this company.
http://www.radicalrc.com/category/A123-Cells-Packs-199

They are about 1/2 the weight of a "Sub C" Nih battery pack, but have far higher momentary ratings on maximum current output.

If you pick up a charger like a Cellpro 4, that will show you exactly how much milliampere hours a flight took, so you can predict how many flights are reasonable on a charge. You can charge these A123 cells as high as your charger will go. I routinely charge mine in 15-20 minutes. And discharge a 12S2P A123 pack at 75 Amperes.

These cells have a FLAT discharge curve, so regardless of info out there, a voltage check is not a good indicator of state of charge. By my actual tests, their voltage only drops by a percent or three from 80% to 20% of capacity.

But what's nice about them, their charging efficiency is near 100%, so if you pull 472 milliampere hours out of them during a few flights, recharging them will take about 472 milliampere hours. And those Cellpro Chargers with their LCD display will let you know exactly how far discharged they got.

Don't ever short one of these batteries though. I did it once, burned the copper wires right out of the insulation. Zero damage to the A123 cells.

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Old 05-05-2011, 06:08 AM   #23
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Originally Posted by kyleservicetech View Post
I'm not certain what those cells are, that size cell is generally 1000 mah, not 2300 mah.

If you're radio will handle a 5 cell nih pack, the 2 cell 2300 Mah A123 battery is a direct drop in, no regulator is required.

I'll do some research to learn whether or not my receiver (Futaba) can handle a 5 cell nih pack. After looking at the web link you provided, I don't think the batteries I linked are the same at all. The A123 batteries have a much higher output capability.

Thanks again.
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