How to adjust the rudder angle deviation of the rudder angle indicator?

Regarding the rudder angle indicator of the avionics, after a long time of use, we will encounter similar rudder angle deviations. How should we adjust this instrument? And we need to pay attention to a problem when adjusting, that is, this instrument requires professional personnel to adjust the instrument, otherwise it will cause damage to the instrument. Next, let's enter how to adjust the deviation of the rudder angle.

     The rudder angle indicator is a self-aligning machine. There are transmitters and receivers. One transmitter on our ship has eight receivers. The transmitter enters five wires and two excitation wires, three phased three-phase wires, and receives three wires. Their adjustments are mainly to be consistent with the mechanical zero degree of the rudder. Then fix it again. For example, you can switch to any two of the three wires for receiving signals by turning the left rudder to instruct the right rudder.