Problem with Bulltra B1-14

HELP =_= Problem with Bulltra B1-14

Hello,

my bulltra B1-14 had a problem the last time i used it. I was using it lifting and lowering the plow with the right lever when suddenly the up-down movements stops working. When i realized that the plow was stopped (ignoring the lever position) i tried to manually move it up/down with the switch (see image) and it worked. Unfortunately the switch is very hard to move (i must use pliers) so i can't use it for normal use.



I thought it's an electrical problem, since it works with manual movements. I think that it's not a problem in the potentiometer and i tested them both (lever and plow height) measuring kOhms values so they are not broken. I don't know how the electrical board is built but i think that a broken potentiometer should move the plow all up or all down, not letting it in the same position.

To understand the problem i opened the box, i found the board in a bad status (see photo) but a friend of mine says that in his opinion the board is still working and that the problem is not there. What do you whink? What could i test to chech where is the problem?



Can i buy a new board and where?
I can see all cables coming from the tractor, they all have different colors. Is there a map color/destination?

Looking the cables i realized the tractor has 3 electrovalves (photo): the two lower are similar with 2 cables each (i think forward-backward of the same movements), the top one has 4 cables so i tink it has both directions for another movements. Does anyone know which EV move the tilt of the burr (two oil fast connectors, other photo) and wich lift and low the plow?

edit said:

Manually testing i realied that the upper one tilt the burr sending oil in the rear 2 tubes. The mid one lift the burr, the lower lowers the burr.

Click to expand...

front:

rear:


I realized that there is another component connected with the board i don't know what it is for. It's visible from the rear of the tractor: see green rectangle in the image below. What is it for?

edit said:

A workshop man said it's to measure the tracotr actual tilt so the electronic can adjust the burr tilt.

Click to expand...

Thanks

can someone help me?

I***8217;m going to write how i solved the problem to help other people that could have a similar problem but i***8217;ll not write most of information to keep the post as short as possible. If someone need other informations feel free to PM me or to as in the thread.

To solve the problem i initially checked the voltage in every wire, in the external connectors. Next I cut all wires near the board and i tested the wire resistance to understand the color of each wire (the color is visible only near the board due to dirt).
All electrovalves have one side directly connected to +12V, the color of the other side is described above.
When i write Spring_Green i mean a color like #00FF7F

Orange > Lift
Brown > Lower
Blue > Rotate 1
Green > Rotate 2

Yellow > 12V - same connector as 0V (Water)
Spring_Green > 0V - same connector as 12V (yellow)
White/black > 0V - single connector

Yellow/Black > Potentiometer tool actual H, GND
Yellow/White > Potentiometer tool actual H, Signal
Yellow/Red > Potentiometer tool actual H, +V

Blue/Black > Potentiometer tool set H, GND
Blue/White > Potentiometer tool set H, Signal
Blue/Red > Potentiometer tool set H, +V

Green/Black > Potentiometer tool actual tilt, GND
Green/White > Potentiometer tool actual tilt, Signal
Green/Red > Potentiometer tool actual tilt, +V

Spring Green/Black > Female connector, joined with actual tilt when unused, GND
Spring Green/White > Female connector, joined with actual tilt when unused, Signal
Spring Green/Red > Female connector, joined with actual tilt when unused, +V

Black > Rear box (tractor actual tilt?): 0V
White > Rear box (tractor actual tilt?): Signal
White/Red > Rear box (tractor actual tilt?): 12V [to be checked]

Some cables seems to have the same function (Spring_green and White/Black cables).
I currently don't know the function of the the Spring_Green triplet of whire, they are connected to the Green triplet when i'm using a not-tiltable tool and disconnected when i'm using a tiltable tool. I can't find a reason why they should make 3 wires more to bring back a signal they already have in the board.
After this preliminary test i built a trivial project to check how to command valves. A rough scheme is shown in the following image (thanks to http://www.digikey.com/schemeit/)



Basically i connected 4 flyback 4A diodes (https://www.aliexpress.com/item//32717674182.html) and a DPDT switch (https://www.aliexpress.com/item//32718044511.html). Connected this way i can lift and lower but it***8217;s not comfortable so i decided to restore previous features.

I bought 2 buttons with and integrated led, another DPDT button, a rotary encoder for less then 1$ each, on aliexpress. I bought an arduino nano (less than 3$), a perfboard, a DC step down (0.7$ ), 4 mosfet n-ch logic level (i bought IRL2203NPBF).
I connected all together as shown in the following image (HD attached).
[blue = 0V, yellow = 12V, red = 5V, orange = arduino output, green=arduino input]



I used a standard USB cable to program arduino and, for that reason, i ensured that a termination come out of the box.

The result is shown above. Surely it can be done better but i learnt lots of things during the work. As you can see i used a lot of dupont cables and, after the first test, i locked all components with hot glue.






Improvements and variations:

• The biggest difficulties is to close the box after it***8217;s all connected ( I hope not to have to open it again ) because where lower cables enter in the box there are too many things. I put there a big terminal block for +5V and 0V with all relative cables and another terminal block for each cable. Flyback diodes are in that terminal block, probably moving them in the perfboard and avoiding terminal blocks for all cables except than +5V and 0V will make the mounting phase more comfortable
• Even if it can be simplified using multiple colors the dupont way is not beautiful to see. It is very easy to build and it can be mechanically reinforced using hot glue but I think it should be replaced by a PCB. I found some services where you can buy a custom pcb double side for 10$ (https://www.seeedstudio.com/fusion_pcb.html) (10 pcb 100x100mm for 10$, my perfboard is 50x70mm) where you can solder both arduino and the step down. Probably the 4x 2A path must be reinforced with Tin.
• Relay modules are cheaper than n-ch mosfet but takes more space. [that's not true]
• Electromechanical direct movements (manual movements) could be avoided to free a DPDT and to keep the project simplier.
• Led are not bright enought to be seen at daylight. Probably they should be driven with a simple bjt.