The short answer
S-Link is Sleipner’s CAN control network: it connects compatible devices using a backbone, branches, connectors, and terminations designed for this system. eVision refers to a generation of thrusters with integrated power electronics and proportional control based on configuration. The two terms are not interchangeable. To design the complete system, start with the exact references of the thruster, panel, and interfaces, draw the S-Link topology, add the required control power supply and terminations, then separately validate the high-power circuit. Do not transpose the rules NMEA 2000 or the compatibility of an older Side-Power installation without documentation.
Separate power, command, and integration
A thruster system comprises multiple layers. The power circuit connects batteries, protection, circuit breaker, and motor. The command network carries orders and states. Interfaces may finally exchange data with a remote control, third-party joystick, display, or external signal.
This separation avoids a common mistake: believing that a network cable powers the motor, or that connector compatibility proves functional compatibility. The installation diagram for the model remains the reference for each layer.
In the Sleipner catalogue, S-Link cables, commands, interfaces, and thrusters are presented in distinct families to build a verifiable nomenclature.
Understanding the S-Link backbone
Sleipner describes S-Link as a CAN system providing intelligent communication between compatible devices. The range uses dedicated backbone cables, stub cables, connectors, and terminations.
The backbone forms the main line. Equipment connects according to the manual’s topology, using the approved components and lengths. Terminators electrically close the network at the prescribed locations. A stub must not become an improvised secondary backbone.
Before purchasing, map the actual routing: bow thruster, optional stern thruster, panel, automatic circuit breaker, interfaces, and connection points. Record each length. This step limits unnecessary extensions and connectors hidden in inaccessible areas.
Do not confuse S-Link and NMEA 2000
Both rely on CAN communication, but they are not interchangeable networks. Connectors, power supply, messages, and integration rules belong to their respective systems. Do not insert an S-Link device on a NMEA 2000 backbone, or vice versa, without an explicitly documented interface. The NMEA 2000 architecture guide allows comparing topologies without mixing them.
An interface to a display or an external signal has a defined role. For example, the ESI-1 interface is documented to convert a 4–20 mA analog signal to S-Link and control certain specific families. This description does not automatically make every 4–20 mA device suitable: range, logic, power supply, and functions must match the manual.
Locating eVision in the architecture
The eVision thrusters use a design and electronics that enable proportional control across the range. Sleipner publishes for each model datasheets, manuals, wiring diagrams, and schematics. The motor, integrated inverter, voltage, circuit breaker, and control form a single unit.
The practical benefit of variable thrust is precision: light correction to hold the bow, stronger thrust to counter a gust, finer coordination with the stern. This does not exempt you from respecting the duty cycle, temperature limits, or energy balance.
An eVision retrofit announcement must be verified model by model. Record the complete reference of the old thruster, voltage, tunnel, motor, control unit, and accessories. A historical Side-Power brand or identical diameter is not enough to guarantee a direct conversion.
Selecting controls by function
Define the necessary stations: main helm, flybridge, exterior station, or remote control. Decide whether proportional control is required or if a directional command is sufficient. Check status feedback, alarms, priority between stations, and the emergency stop function provided.
The panels and remote controls must appear in the official compatibility list for the configuration. Do not mix an old on/off panel, an S-Link interface, and a presumed eVision function. Bow and stern thruster controls must also respect identification and the direction of operation.
For integration with a joystick or third-party system, use Sleipner’s dedicated document. Identify who is responsible for the logic, safety features, and shutdown. A successful physical connection is not enough to validate failure scenarios.
Powering and terminating the network correctly
The S-Link network receives its power supply according to Sleipner’s diagrams. Use the recommended cable and protection. Check the voltage at the farthest devices and avoid injecting multiple unplanned power supplies. The high-power circuit should be routed close to the battery and power production hubs.
Verify the presence and position of terminations. Label both ends of each cable and keep connections accessible and dry according to their protection level. Keyed connectors simplify assembly, but they do not correct poor topology.
Physically separate signal cables from high-power conductors and sources of interference as far as possible, in accordance with the manual. Support the harnesses and protect them against tension, abrasion and stagnant water.
Commission in stages
Before powering the motor, check the continuity of the network, connectors, terminations and circuit polarity. Power up the control unit, verify device detection and log any fault codes.
Then test each direction with a brief pulse in a safe area. Confirm control stations, remote control, stop function and alarms. On a proportional system, gradually increase the setpoint and monitor voltage, noise and behaviour.
Keep the "as-built" schematic, references and document versions. On future upgrades, this record is worth more than a harness whose origin no one knows.
Official sources
- Sleipner — S-Link interface overview and network FAQ
- Sleipner — ESI-1 interface, 4–20 mA signal and documents
- Sleipner — E100 eVision tunnel bow/stern thruster, compatibilities and manuals
- Sleipner — eVision range
