Overcurrent Error of Board 2 Part 1

Now we are going to examine this error. The first point is to examine the “command” problem. By replacing the “command”, it is possible to find out if the “command” is healthy or not. We replace the “command” of this side with the “command” of the other side which we have detached before, take a test and turn the device on. If the overcurrent error of board 2 still remains, it means that the “command” is healthy and we need to check other possibilities; if the error is eliminated, the overcurrent error of board 2 is eliminated, it means that its command is damaged. Lets suppose that the overcurrent error of board 2 still remains as the command has be replaced. To do this need to open the Main Switching. Open the Main switching, open the two screws at the top, three in the middle and two screws on the end of the board. Then detach the Main switching. To test these items, test the diodes that are on the switching module.

The first diode is the one that is located on the transformer and to test this diode, It needs to be released it from one side because it is connected to the both sides of the transformer and if a diode test is performed it will show short-circuit and it won’t be able to find out whether the diode is healthy or not. Here there are three diodes to test. There are ten diodes here and two other diodes that are located at the voltage and current output. First, following the instructions that were given earlier, we detach one of the sides of the diode that is located on the two sides of the transformer. The diode test of this diode must show overload in the both sides (this is a two-way diode and the result must be overload in the both sides). If the route of the voltage is displayed in one side, this diode is probably damaged. If the diode is overload in the both sides, it is healthy. If the diode is damaged, remove the diode from the circuit like this. Take the diode completely out of the circuit and if it is possible, replace it but if there isn’t a diode, we can just remove this damaged diode from the circuit and the device will be fine.

The next diodes that need to be tested are these three diodes. The first diode must show overload from one side and a value as big as 0/8 from the other side. The second and third diodes are tested in the same way. If any of these diodes is damaged, we can just remove them from the circuit like we did with the diode that was on the both sides of the transformer and this will not cause any problem for the device. If we have a spare diode, we can replace it with the damaged part. The next diodes that need to be tested are these ten diodes that are located here. These diodes pass the current from one side and their other side is a closed route.

One notable point is that this diode belongs to the DC voltage output. If this diode is burned out, it shows us that this other two diodes are burned out. In the first stage, we need to remove this diode from the circuit and then test these two diodes. Usually these two are shown to be healthy. This means that this diode’s burning out causes the other two diodes to be showed as burned out. But when this diode is removed from the circuit, there is no sign of damage in these two diodes and they are healthy and this problem is solved by removing from the circuit.

These two here are the next diodes. We need to release them from one side like this and then perform a diode test like this. They should be overload from both sides; if they let the current pass from one side or show short-circuit then that diode is burned out and must be removed or replaced with a spare part if possible.