picboard problem

HI,
Yes it is possible to replace the diode by a 1 N4001 but the result will be not as good as expected: the 1N 4001 is a standard diode (silicon) and the diode needed for the "free wheel" of the picboard (this is the right name for this component !) as to be a schottky diode. The difference between these components is the response time that is much quicker for the schottky one.
So, if you want everything work good and for a long time, replace the faultly diode by any schottky diode rated for 3 Amp/20 Volts.
It will protect your picboard and, most important, the speed controler will work better at slow seed.

Best regards,

Comar,
you're probably right about the diode, but i heard that it was a 1N4004 and not a 4001.

(2 cents)

------------------
johnk NJJ011101




[This message has been edited by johnk (edited 04-27-2001).]

There is no diference in response time between 1N4001 and 1N 4004. The firt 1 is rated for 100 V and the second 1 for 400 V.
That's all.



------------------
Comar

i figured that.( i work on guitar amplifiers/ big and bulky)

so are you saying that the piccoboard does in fact use an actual schottky originally?

------------------
johnk NJJ011101

SPeed is not the issue here ,

The lower forward voltage of a schottky diode is much more important to reduce the negative voltage generated by the motor at cut-off periods by the esc .
with a 1NXXX , the motor will get hotter and efficienty will go down .
I've build enough ESC's from scratch to know .
the problem is to find these SMD components in small amounts !! .
For fast replacements , the 1NXXX will do .
regards ,

Koen VG

Hi KOEN,
you're right when you say that efficency is affected by this diode but did you try any ESC with and without this diode ?
The difference at low rpm is very important. It is almost impossible to control a motor at low speed if the diode is not a good one.
And yes, the motor will be hot if the diode is not a schottky one...
There is a lot of schottky diodes (Motorola MBR serie for example) that fit on the pic board and they are better than 1N400x

------------------
Comar

I am following the discussion on the correct diode for the PiccoBoard replacement, but I have lost trace of who need this diode!!
I have the right one: schottky diode 3A 40V in SMD technology, so I can send the replacement diode only if I know who need it!

ciao,



------------------
Michele IMM091500

[TAW]

OK,

I have managed to toast my piccoboard !!!

See http://www.ikarus-modellbau.de/ubb/F...ML/003416.html for details.

Can anyone tell me if it is normal for the main motor to run at full speed when this happens???

There is no control over it at all, but the tail motor and gyro work fine!!!

Have tried a 1N4004, but it makes no difference. So I am thinking of getting a seperate ESC for the main motor.

------------------
Tim G-TAW

Have a look at My Pic Pics Page

Hi comar ,

Could you e-mail me your e-mail adress ,i need it to send you your photos about the heading lock module.

My e-mail adress is in the top and in my profile

Thanks

------------------
Nath FAN250101

Have a look at my Piccolo's pics http://albums.photopoint.com/j/AlbumList?u=1612335&f=0



[This message has been edited by Nath (edited 04-30-2001).]

TAW,

my friend had that same problem, where the main motor runs at full blast and cannot be controlled. the only difference i see is that the servos also worked just fine.