[CA] Replacement for S1G E12124

[k17]

Our S1G E12124 Course Computer was flooded with salt water and needs to be replaced. We have found similar used units for sale, but none with the same Raymarine product code / part number E12124. Available S1G units are designated E12115 or E12123 or E12180, etc.
Is there a list of S1G unit product codes / part numbers that would work with our existing (and undamaged) Type 1 Linear Drive, Rudder Reference Unit and ST6001+ control Head?

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum k17,

E15021 was the part number assigned to the S1G Autopilot Course Computer alone .
This part number may be found on the serial number label affixed to the back side of the autopilot course computer. This is the part which one would have ordered to replace a failed S1G Autopilot Course Computer.

E12115 was the part number assigned to the package which included the S1G, fluxgate compass, rudder reference transducer, and documentation pack

The S1G was also bundled with other autopilot components to create S1G autopilot systems (e.g. fluxgate compass, rudder reference transducer, autopilot control head, and drive unit). These included, but are not limited to the following:
- E12120
- E12121
- E12122
- E12123
- E12124
- E12125
- E12152
- E12154

[k17]

We were unable to obtain the S1G E15021 replacement. Would a S2G E12091 be compatible (direct replacement) with the existing Type 1 Linear Drive, Rudder Reference Unit and ST6001+ control Head?

[Chuck - Raymarine - Moderator]

k17,

Q1. Would a S2G E12091 be compatible (direct replacement) with the existing Type 1 Linear Drive, Rudder Reference Unit and ST6001+ control Head?
A1. Yes. Such substitutions to a higher rated autopilot course computer are permissible for autopilots featuring mechanical drive units, but may not be acceptable for autopilots featuring hydraulic drive units.

[k17]

I have managed to obtain a used S1G - E12115 Course Computer. Inside the case there is a component with the shape of a small metal doughnut that has a pair of wires wrapped around it. This component is not mounted in any way and is held in place only by the looped wires.
Is this normal?... and if not, how should it be secured?

[Chuck - Raymarine - Moderator]

k17,

The object which you have referred to is a RF choke on cable for the S1G's gyro component. RF chokes are designed to eliminate or reduce RF emissions from a device, thereby preventing interference within other electronics such as VHF radios, FM radios, etc.. The early S1Gs featured the metal cased gyro and did not require a RF choke. Accordingly, the RF choke may be removed.

[skarlson]

I have a similar issue. I have a port issue with the auto pilot computer on my boat. The Serial Number is E12121. What course computers are direct replacements for it. I am finding similar units on line including a E12091 and E12120 and E12054. Dont know which serial units will be a plug and play match

[Chuck - Raymarine - Moderator]

Skarlson,

As indicated above, the S1G was bundled with other autopilot components to create S1G autopilot systems (e.g. fluxgate compass, rudder reference transducer, autopilot control head, and drive unit). These bundles included the bundle part #E12121. None of Raymarine's currently manufactured autopilots (i.e. the Evolution autopilots) may be used a direct replacement for the S1G autopilot course computer. However, the currently installed drive unit which is currently interfaced to the S1G may be used with an Evolution autopilot and it is quite possible that the Evolution autopilot may be able to be adapted for use with the other components of your marine electronics system (we would need to know the makes and models of each component to ensure compatibility).

The only direct replacement for a S1G autopilot course computer would be another S1G autopilot course computer, S2G (also retired), or X10 autopilot course computer (also retired), which would need to be sourced from the second hand market, as these autopilot course computers have been retired for some time.