For owners and marine installers · Firmware 2.3
For small commercial fishing boats, crewed or single-handed. Find the right Guardian parts for your engine's stop system, see how it wires in, then follow the full installation and test procedure.
Answer what you know. If you're unsure, pick "Not sure" and we'll show you how to check.
An outboard fit usually takes 1–2 hours. Inboard diesel systems, especially with a relay box, can take up to half a day.
EXPOLASGUARDEXT (+0.75m on switch and power cables), £37EXPGUARDSWITCHNUTLONG for panels up to 30mm, £18EXPOLASMEC.Use the checker above to see the exact wiring and diagram for your boat.
A bucket or glass won't block the signal, and walking away along the pontoon can keep the link for up to 100ft. Only submerging the tag in open water gives a true test. Photograph the fitted kit and record the test for your grant claim.
Set each tag's mode in the OLAS app. The mode is stored on the Guardian.
If the tag goes out of range, the relay cuts the engine within 2 seconds (adjustable), the alarm sounds and the app shows the MOB alert. After 7 seconds the engine can be restarted for the rescue. Bring the tag back within 1m of the hub to re-track it.
Sounds the alarm and triggers the MOB alert, but doesn't stop the engine, so a rescue can start straight away. The tag reconnects automatically when it comes back into range.
A kill-cord mode for boats under 35ft. Stops the vessel if the tag moves beyond a calibrated distance from the hub. It doesn't raise MOB alerts.
For a single tracked tag. The app sends an SMS with vessel name, time and location to your emergency contact after a set delay (minimum 1 minute). Needs at least a 2G signal.
Hold the control switch for 2 seconds to stop tracking (solid red). Press once to resume. Hold 4 seconds to switch Guardian off.
An immobiliser for outboard engines only. Do not use Smart Lock on inboard diesel or Volvo Penta engines.
Diesel parts selection
| Engines | Stop system | Circuit | Current | Relay box | Diagram |
|---|---|---|---|---|---|
| Single | Open to stop | Direct | Above 2A | EXPOLASGDRLY | 1RLYOS |
| Single | Open to stop | Indirect | Up to 2A | Not needed | 1OS |
| Single | Close to stop | Direct | Above 2A | EXPOLASGDRLY | 1RLYCS |
| Single | Close to stop | Indirect | Up to 2A | Not needed | 1CS |
| Twin | Open to stop | Direct | Above 2A | EXPOLASGDRLY2 | 2RLYOS |
| Twin | Open to stop | Indirect | – | EXPOLASGDRLY2 | 2RLYOS |
| Twin | Close to stop | Direct | Above 2A | EXPOLASGDRLY2 | 2RLYCS |
| Twin | Close to stop | Indirect | Contact us with engine details | ||
All configurations apply to 12V and 24V DC. Relay boxes are built to order. Standard lead time is 1 month, so order as soon as your grant is acknowledged.
Outboard kill-switch wire colours
| Engine brand | Typical colour |
|---|---|
| Evinrude / Johnson | Black/yellow |
| Mercury | Black/yellow |
| Honda | Black/red |
| Suzuki | Green |
| Yamaha | White |
Always confirm wiring with your engine manufacturer.
Guardian hub
| Power | 10–32V DC, 13–17mA |
|---|---|
| Internal relay | Up to 2A |
| Cut-off | ~2s after tag lost (adjustable), restart after 7s |
| Tags tracked | Up to 25 |
| Vessel length | Up to 50ft, depending on construction |
| Alarm | 85dB buzzer, 55lm light |
| Size / weight | 92 × 90 × 38mm, 100g |
Diesel relay box
| Part numbers | EXPOLASGDRLY single, EXPOLASGDRLY2 twin |
|---|---|
| Relay | SPDT, 12V DC coil, 30A. Durakool DG56A-7011-76-1012 or direct equivalent |
| Power input | 12/24V DC |
| Stop circuit wire | 14 AWG (2.5mm²) |
| Power wire | 17 AWG (1mm²) |
| Enclosure | IP66 polypropylene, 104 × 104 × 70mm, 83mm mounting centres |
| Cables | Power 350mm, Guardian 420mm (750mm extension available), engine relay 350mm |
| Supplied | 2 × A4 stainless screws and washers, 4 × butt splices (14–16 AWG) |
| Temperature | −10°C to +40°C |
Control switch signals
| Situation | What you see and hear |
|---|---|
| Tracking, all OK | Solid green |
| No tags in range | Green/red alternating, beeps increasing every minute |
| New tag tracked | Red double flash, double beep |
| MOB alert | Constant red, hub high red, beep every second |
| Standby | Solid red |
| Tag battery under 20% | Red flash every 10 seconds |
| Tag battery under 10% | Beep every 5 minutes |
If the switch isn't lit, Guardian has no power and the engine will not be cut. Check it's lit every time you go to sea.
Technical help
Ultimate Sports Engineering
+44 (0)1798 839300
Sales olas@use.group
Service service@use.group