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Old Feb 18, 2013, 11:03 AM
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Electraglide's Avatar
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Thanks Dennis and mike-O.
I wrote and asked mehlin/Flytron what he thought about it, just waiting for an answer. I did hook it up to a motor and ESC on a test bench and it did smoke the ESC. I can not understand what I did wrong???
It was not hooked up to the OSD s no harm done to that.
Best regards Poul.
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Old Feb 18, 2013, 11:41 AM
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Dennis Frie's Avatar
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Quote:
Originally Posted by Electraglide View Post
Thanks Dennis and mike-O.
I wrote and asked mehlin/Flytron what he thought about it, just waiting for an answer. I did hook it up to a motor and ESC on a test bench and it did smoke the ESC. I can not understand what I did wrong???
It was not hooked up to the OSD s no harm done to that.
Best regards Poul.
Sorry to hear that
Next time you are welcome to bring all the hardware, so we can get it hooked up right.

I don't use deans myself and can't see if they are mounted correct in regard to polarity. The only logic reason for your smoked ESC, is wrong polarity. Have you checked the polarity on the deans you have soldered on the current-sensor?
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Old Feb 18, 2013, 12:02 PM
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If you look at a Deans connector as a "T", the upper, horizontal bar of the "T" is plus (+). The connectors seems to be correctly mounted on the sensor.

If the ESC had a problem (short circuit or similar) all along, that could explain the hot sensor. Then, eventually, the ESC let out the magic smoke
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Old Feb 18, 2013, 12:57 PM
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Danmark, Hovedstaden, Hellerup
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Quote:
Originally Posted by Dennis Frie View Post
Sorry to hear that
Next time you are welcome to bring all the hardware, so we can get it hooked up right.

I don't use deans myself and can't see if they are mounted correct in regard to polarity. The only logic reason for your smoked ESC, is wrong polarity. Have you checked the polarity on the deans you have soldered on the current-sensor?
Polarity was checked before mounting, ESC did work before using the current sensor. I have ben using Deans in most og my A/C and n most og my batterys, so I don't think that the problem is reverced polarity.
Thanks for your backup. I'll be contacting you during this week, Best regard Poul.
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Old Feb 18, 2013, 08:38 PM
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Calgary, Alberta, Canada
Joined Jun 2009
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Settings in config.h

From config.h
//===========================
// Menu control channel
//===========================
#define MENU_CONTROL_CH1 1 // Up/down value
#define MENU_CONTROL_CH2 4 // Enter menu and exit menu + up/down in menu

**The above works ok for me. I have defined Ch 1 as Aileron and Ch 4 as elevator. The Up/Down is very sensitive for me. I have to be very careful not to overshoot where I want to stop.


//===========================
// Use channel to change OSD-layout?
//===========================
#define USE_OSD_CONTROL_CHANNEL 1
#define OSD_CONTROL_CHANNEL 5

I have Ch 5 assigned to "Gear" and the channel is changing in the PPM Show screen. But I can't see it doing anything. Is it used for anything?

I have the OSD powered from the PPM channel and my camera/VTx from a separate BEC. When I plug the system in, the OSD screen doesn't always come up although video is good. If I power down the receiver(turns off the OSD), the video fades somewhat, but picture is still viewable, so I know the OSD is doing something, but no display. If I plug and unplug a few times, it usually kicks in, but no discernible order and sometimes can't make it start at all. Is this a video sync issue, and how can I make it start always?

When you are going flying, what's the order of doing things? Just plug in power, wait for GPS lock and launch? What starts the timer in the OSD? Do you set "Home" and then launch?

Bill
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Old Feb 18, 2013, 11:13 PM
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That resistor is rated at 2W, and can sustain a max of about 32A. With the two resistors you get 4w/62a max. Very scary!

This is why i designed my own current sensor...
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Last edited by Ascended; Feb 19, 2013 at 12:10 AM. Reason: didnt see there was another page to the thread.
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Old Feb 19, 2013, 04:21 AM
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Originally Posted by Ascended View Post
That resistor is rated at 2W, and can sustain a max of about 32A. With the two resistors you get 4w/62a max. Very scary!

This is why i designed my own current sensor...
Are you talking about the one he got -> its rated at 50A so should be below 62A.
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Old Feb 19, 2013, 06:15 AM
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I believe Eletraglide's sensor was ordered as a 100A type. It seems that Flytron has mounted two 0.001ohm shunt resistors instead of one 0.0005ohm resistor.

In that respect it qualifies as the advertised "0.0005ohm, 100A sensor", but one can argue about the 100A rating.

I'm sure it will tolerate peak or bursts of 100A, but it will indeed get very hot very quickly with a sustained load of 100A. I wouldn't try that for more than some tenths of a second...
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Old Feb 19, 2013, 07:13 AM
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Denmark, Capital Region of Denmark, Naerum
Joined Feb 2011
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Quote:
Originally Posted by SupraGo View Post
From config.h
//===========================
// Menu control channel
//===========================
#define MENU_CONTROL_CH1 1 // Up/down value
#define MENU_CONTROL_CH2 4 // Enter menu and exit menu + up/down in menu

**The above works ok for me. I have defined Ch 1 as Aileron and Ch 4 as elevator. The Up/Down is very sensitive for me. I have to be very careful not to overshoot where I want to stop.


//===========================
// Use channel to change OSD-layout?
//===========================
#define USE_OSD_CONTROL_CHANNEL 1
#define OSD_CONTROL_CHANNEL 5

I have Ch 5 assigned to "Gear" and the channel is changing in the PPM Show screen. But I can't see it doing anything. Is it used for anything?

I have the OSD powered from the PPM channel and my camera/VTx from a separate BEC. When I plug the system in, the OSD screen doesn't always come up although video is good. If I power down the receiver(turns off the OSD), the video fades somewhat, but picture is still viewable, so I know the OSD is doing something, but no display. If I plug and unplug a few times, it usually kicks in, but no discernible order and sometimes can't make it start at all. Is this a video sync issue, and how can I make it start always?

When you are going flying, what's the order of doing things? Just plug in power, wait for GPS lock and launch? What starts the timer in the OSD? Do you set "Home" and then launch?

Bill
If I remember (next time I look at the code), Ill check the menu-sensitivity and perhaps make it possible to change.

The "Use channel to change layout" is currently only used to turn artificial horizon on/off. I haven't yet decided how much I will turn on/off. Should preferably be customizable in some way

It sounds like the OSD is powered from somewhere else. When you turn it off, you say the video kinda fade? Would you mind measuring the voltage between Vcc and a ground-pad (with "faded" video)? It sounds to me like the OSD is powered anyway, but not with the required 5 volt. If a small signal/voltage is available, it might be enough to run Atmega328 but not MAX7456. That will cause Atmega328 to boot without MAX7456 running. That will give the missing overlay. If you continue to have problems just let me know, it should only be a question about a little delay to make sure MAX7456 have started properly before commands are send from Atmega328.

I normally turn on my plane as first thing, set up my antenna, connect googles etc. If home-positio have been set (satellites found), I just launch.

The timer will start as soon as the OSD starts (but it uses GPS-time and a GPS must be connected, unless you have changed it in the config-file). The timer will be reset when home-position is set.
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Old Feb 19, 2013, 07:19 AM
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Quote:
Originally Posted by Ascended View Post
That resistor is rated at 2W, and can sustain a max of about 32A. With the two resistors you get 4w/62a max. Very scary!

This is why i designed my own current sensor...
Quote:
Originally Posted by msev View Post
Are you talking about the one he got -> its rated at 50A so should be below 62A.
No, 32A continuously and 62A peak. It seems quite normal to use the shunt-resistors close to the limit in this hobby (or even above).

In smaller planes it's not a problem. In large planes I normally use 2 x parallel batteries, I personally only connect the current-sensor on one battery. Not 100% perfect in regard to current-measure, but the current-sensor only have to deal with 1/4 power and if the shunt burns out, I still have another battery connected.

Just call me paranoid, but Ive seen electronic fail too many times
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Old Feb 19, 2013, 07:27 AM
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So the 50A sensor cannot maintain 50A for 10 seconds of full throttle for example?
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Old Feb 19, 2013, 07:38 AM
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Originally Posted by msev View Post
So the 50A sensor cannot maintain 50A for 10 seconds of full throttle for example?
The rating depends on the application it's used in. On current-sensors, you normally have a good thick cobber-area around the shunt-resistor and some thick cobber-cables/wires. They will be able to move a good amount of heat from the shunt-resistor.

A lot of people have been using this kind of current-sensor without any problems (myself included), but just be aware of the limitations.

I cant give you an accurate A-rating, it depends on your cooling. Give it a WOT for 10 seconds on ground and take the temperature if you are worried.
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Old Feb 19, 2013, 09:28 AM
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Danmark, Hovedstaden, Hellerup
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Quote:
Originally Posted by Ascended View Post
That resistor is rated at 2W, and can sustain a max of about 32A. With the two resistors you get 4w/62a max. Very scary!

This is why i designed my own current sensor...
I'd Rather be safe than sorry, therefore do you have a link/tread regarding your current sensor.
I know that I never going to need 100A on my Easy Glider but on my large 4m "Epsilon XL" I just might top at 100A.

I still havent heard anything from Mehlin/Flytron yet.
Best regards
Poul
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Old Feb 19, 2013, 09:45 AM
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Your 4 meter glider looks very nice
I would love to see it in action some day.

The current-sensor mentioned by Ascended is not available yet.
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Old Feb 19, 2013, 04:39 PM
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Joined Jul 2008
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Originally Posted by Dennis Frie View Post
Even though FrSky performs pretty well compared to similar RC-links, I don't see it as an ideal RC-link for FPV. If it was a quick add-on in software, I wouldn't mind, but adding extra hardware to support FrSky telemetry will not be done.

With the RF-links Ascended have developed, telemetry is already in work

By the way - you might be able to use the Serial output if you want. The serial-communication is only used with GPS, but you only need the USART TX from Atmega if you configure the GPS on start-up.
Hm, you mean GPS configuration on start up may be optional, or does it depend on GPS module type? If it does depend on GPS module type, wondering if this would allow to leave tx pin free:
http://hobbyking.com/hobbyking/store...?strSearch=gps

On the other hand, how complicated would be to adjust pcb for additional serial communication port?
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