Having hooked the screw-driver, we uncover the main unit.

Safety locks are established between spring plugs. At safety locks of 8A the insulator of black color, 16A – green. They are located in the order of numbers from left to right.

Having wrung out the lower or top plug, we take out a faulty safety lock and we establish a new safety lock of the corresponding face value (see the table the Electric chains protected by fuses).

We latch a cover into place.

Similarly we change safety locks in the additional block.