Active trailers: change ID number

Changing the hardware / number on the sowing unit when replacing a unit.

Before starting this task, please be aware that electronic boards can be damaged beyond repair by static electricity. So please take your precautions to avoid static electricity when performing this task.

When adding extra sowing units or replacing broken ones the sowing unit has to have the correct number.

The sowing units are numbered from 1 to [Number of sowing units on the Droid] starting with number 1 being the leftmost one when standing behind the droid and looking at the sowing units. Then the unit’s number / addresses count up going towards the right. (count only the active trailers not the passive)

1. Disconnect the cables from the active trailer.
   The PCB is located behind the plate where the cables are connected.
2. Unscrew the 6 large screws on the active trailer front plate
   
   
3. Look out for static electricity grab the iron frame or alike as often as possible to discharge your self as often as possible during this and the next steps.
   
   
4. Now carefully pull the PCB out of the seeding unit housing.
   Do not disconnect any wires and be very careful not to bend the wires since some of them are optical fibres and break easily.
   
   When the PCB is out of the housing as much as shown in the picture below, it is enough to perform the actual task.
   
   
5. On the board you will find 2 dials, marked with a red and a green arrow in the image below.
   
   The dial marked with the green arrow is counting the units (e.g. 1,2,3...)
   The dial marked with a red arrow is counting tents (e.g. 10,20,30...)
   
   
   E.g. in the image below, it's shown the dial for active trailer no. 1:
   
   
   

   
   You change the dials by turning the white knob with a small screw driver until the arrow you turned is pointing on the number you wish to set it on. 
   
   

6. When done setting the dials you carefully assemble the unit in the reverse order as you took it apart. Again, being careful not to bend the wires too much.