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bazza
10-15-2005, 12:01 PM
Hi all

This is a first post SOS, I've had an electris piper cub for a while and it's been great electric, no mess and ready in seconds etc. Everything has been fine until yesterday when I foolishly took delivery of a small brushless motor and controller ( an ebay impulse buy!). Tried to fit it today complete with 7.5 volt lipo pack. The servos operate okay but the controller sounds some sort of warbling alarm as soon as i connect the battery.
This has me baffled, i was never aware that controllers had any sort of audio ability but its pretty loud.I've checked all the wiring for polarity and its all okay.
Can anyone help? i realise i am trying to run before i can walk but the tempation for more speed and power was too much!

regards

barry

Jeremy Z
10-15-2005, 01:40 PM
I realize there are people here who know better than I do, but I can try to give you some things to check for.

Is it possible that it's sensing a servo reverse condition?

An alarm like that is definitely trying to tell you something.

Did you read the literature (if any) that came with it? (RTFM ;) )

If you know the polarity is right, my guess would be that 7.5 V is not a match for the controller. It is probably rated for something less. Is there a voltage rating on the controller?

If you're sure it's the right voltage rating, you should drop the seller a line and see if the seller has any ideas.

Jeremy

watt_the?!
10-15-2005, 01:56 PM
Hi all

.....The servos operate okay but the controller sounds some sort of warbling alarm as soon as i connect the battery.
....



sound is good. most ESCs do this. there is a ''good sound'' and a ''bad sound''- (or no sound).

you'll know what the good sound is when your motor runs and your servos are all good also.

then if you switch wires on the motor, or connect the ESC incorrectly to your Tx, you'll get the bad sound, or no sound.

welcome aboard!

Tim.

flypaper 2
10-15-2005, 02:28 PM
Barry:
Sound is good, as Tim says. Don't know what kind you have but castle Creations gives a musical tune when you plug it in. I think it's a Rolling Stones tune but not sure:p If the throttle is set halfway, the motor is unarmed. When you go to low throttle it will give a beep to tell you the motor is live. When you first plug it, at the end it will give two or three beeps telling you how many cells are installed and it gives the appropriate signal to the ESC to tell it what voltage to shut down at. A lot of crap going on with those little beeps:D Hope this helps.

meegosh
10-15-2005, 06:44 PM
My R/C trucks did this too. It is a good thing like everyone is saying. That is awesome that the castle creations plays a tune! :D Whenever I would set the trims on my throttle for my truck the ESC would make a sound letting me know exactly where it starts to accelerate rather than idle. Kinda convienent for resetting your trims if some newb messed with them. :cool:

flypaper 2
10-15-2005, 08:18 PM
Actually it's the motor making the noise somewhat like a doorbell with the 60 cycles pulsing througha coil, but going through the motor coils programmed by the ESC. notice it won't do it with the motor unplugged.

VIC VIC
10-16-2005, 02:55 AM
Hi all

This is a first post SOS, I've had an electris piper cub for a while and it's been great electric, no mess and ready in seconds etc. Everything has been fine until yesterday when I foolishly took delivery of a small brushless motor and controller ( an ebay impulse buy!). Tried to fit it today complete with 7.5 volt lipo pack. The servos operate okay but the controller sounds some sort of warbling alarm as soon as i connect the battery.
This has me baffled, i was never aware that controllers had any sort of audio ability but its pretty loud.I've checked all the wiring for polarity and its all okay.
Can anyone help? i realise i am trying to run before i can walk but the tempation for more speed and power was too much!

regards

barry

Maybe que voltaje cutoff of the ESC is set for a 3Cell LiPo batt, this means that the ESC is "seing" a discharged battery even though it is fully charged. Do you know the voltaje rating of the ESC? can you reprogram it?

twostrokin1
10-16-2005, 08:55 AM
i agree with vic ,,,most brushless esc come programed for factory for lipos and will not run proper with other batts. most of the time it wont work at all...go to website of esc and see how to program it to your battery type

bazza
10-16-2005, 12:04 PM
Hi

Many thanks to the helpful replies, in particular Smaug who suggested that my receiver was unhappy with 7.5v. I just added a jumper to the esc board which fed the rx with 5.5v and hey presto I had power!! and how!!
No matter how many articles I had read on brushless power it couldn't equal trying it. Even on 7.5v lipo spinning an 8inch prop my test bed plane (my only one!) can lift its weight vertically.
Off to the field now for some test flights.
My next plan is back to ebay for a 3 cell lipo pack!

thanks again

barry

watt_the?!
10-16-2005, 12:20 PM
Hi

..... I just added a jumper to the esc board which fed the rx with 5.5v and hey presto I had power!! and how!!
........


not sure i understand. it doesnt sound right to me. never heard of this being done before either.

why would the rx need 5.5V?

tim

flypaper 2
10-16-2005, 12:35 PM
Not sure I understand either. Bazza, Did you have a 4.8 batt. and the ESC plugged into the reciever at the same time? Normally the ESC drops the voltage down from whatever the batt. voltage is, to 5.5 volts to operate the rcvr and servos.

bazza
10-17-2005, 08:39 AM
Hi

I'm not sure exactly what I did, but it worked. From the ESC motor supply end I have the usual red/black/white wires direct to the motor. there is also a thin double cable from the motor end which has a removable jumper on the end. The 3inch by I inch leaflet that came with the esc has this double wire listed as 2/3 Lipo. the following is typed underneath,

2/3 lipoly switch: connect 2 Lipoly (5v cut off)
disconnect 3 lipoly ( 7.5 volt cut off )

Is this something to do with not letting the battery discharge too low??

regards

bazza

watt_the?!
10-17-2005, 10:23 AM
Hi

I'm not sure exactly what I did, but it worked. From the ESC motor supply end I have the usual red/black/white wires direct to the motor. there is also a thin double cable from the motor end which has a removable jumper on the end. The 3inch by I inch leaflet that came with the esc has this double wire listed as 2/3 Lipo. the following is typed underneath,

2/3 lipoly switch: connect 2 Lipoly (5v cut off)
disconnect 3 lipoly ( 7.5 volt cut off )

Is this something to do with not letting the battery discharge too low??

regards

bazza

bingo there you have it. yes, with the jumper not on, you have 7.5V cutoff, with it on, you have 2 or 3 lipo only, 5v cutoff.