Code of Federal Regulations Title 46. Shipping § 46.113.40–10 Detailed requirements

(a) Each rudder angle indicator system must have a transmitter at the rudder head that is actuated by movement of the rudder with the angular movements of the rudder transmitted to a remote indicator or indicators. This system must be independent of all other systems and not receive power or signal from the steering gear control, autopilot, or dynamic positioning systems. However, the indicator may be physically located on a control console, such as an integrated bridge system, if it is readily visible by the helmsman at the steering stand.

(b) Each electric component or its enclosure must meet Type 4 or 4X of NEMA 250 or IP 56 of IEC 60529 (both incorporated by reference;  see 46 CFR 110.10–1) requirements.