One sensor.
Every tank.

• Precise, stable readings with no moving parts and no holes below the liquid line; a low-profile body (≈32.5 mm high) for tight spaces.
• Top-mount radar measures through plastic tank lids — and on metal tanks via a proper opening/adapter — reducing installation risk and ongoing maintenance.

• Pros: non-contact, no fouling or corrosion, app-based setup, millimeter-level accuracy, long life.
• Cons: must mount on top; through-lid works only with plastic (for metal tanks use an opening/adapter); price is higher than basic float senders but far lower than other external radar options.

• Top-mount, no tank penetration: nothing inside the tank; no side or bottom drilling.
• Peel-and-stick mounting: clean and dry the surface, then remove the liner and bond the sender directly to a plastic lid; for metal tanks, bond it to the approved adapter.
• Clear line-of-sight: through-lid on plastic; for metal, the adapter provides the opening so the radar looks straight down.
• App commissioning: quick Bluetooth setup and calibration in the Simarine Connect app.

• STR1: analogue outputs (0–190 Ω / 240–33 Ω / 0–5 V).
• STR2: NMEA 2000 (PGN 127505).
• If you only need local wireless app setup and monitoring with no network integration, pick STR1 — the more cost-effective option.

Both STR1 and STR2 are covered by a full 3-year warranty.

• STR1: analogue gauges and controllers using 0–190 Ω, 240–33 Ω, or 0–5 V — all three outputs are available simultaneously.
• STR2: NMEA 2000 displays and MFDs.

• No. STR1 can feed third-party analogue inputs.
• STR2 publishes to the NMEA 2000 bus and works with any compatible display.

• STR1: use the analogue standard your device expects (0–190 Ω / 240–33 Ω / 0–5 V).
• STR2: works with MFDs that receive PGN 127505 (Fluid Level) — e.g. Simrad / Lowrance / B&G (NSX, Zeus, NSS families) and Raymarine Axiom. Note: many Garmin models show 127505 for Fuel only; check your model's PGN support for other fluids.

Yes — 0–190 Ω, 240–33 Ω, and 0–5 V can be used simultaneously.

Yes — use the 240–33 Ω mode.

PGN 127505 (Fluid Level); typical network update about 0.5 Hz.

8–35 V DC operating; typical current ~14–20 mA @ 12 V.

Yes — follow system standards; place a suitable inline fuse near the power source.

Longer cable on resistive outputs (0–190 Ω, 240–33 Ω) can cause errors due to cable resistance. (Applies to those two outputs.)

Through-lid measurement works on plastic or fibreglass (GRP) tank tops that are flat and rigid. For metal tanks, bond the S5 metal tank adapter (available as a separate item); do not bond directly to metal. The adapter provides a non-metallic window and a flat mounting surface so the radar has a clear, vertical line-of-sight into the tank.

150–2000 mm total tank height.

• Top-mount only. Sensor faces straight down; bottom surface parallel to the liquid at rest.
• Surface prep: flat, rigid, clean, dry area.
• Peel-and-stick: remove liner, place flat, press firmly and hold.
• Metal tanks: bond to the S5 metal tank adapter, not directly to metal.
• Cable strain relief: secure the cable so it cannot pull or twist the sensor or peel the tape.

The beam must be vertical. Use a wedge, spacer, or adapter to correct angle; note that wedges and adapters may affect measurement.

Avoid above baffle walls or near strong inlets or return jets — or any complex feature that could reflect the beam. Keep at least a few centimeters from the edge; ideally install near the tank center.

Yes. A one-time initialization is required in the app, where the tank name, tank volume, units (e.g. liters), and sensor calibration are defined. The tank height can either be entered manually or obtained automatically by the sensor if the tank is empty (automatic empty-tank calibration). Important: do not perform initial sensor calibration before mounting the sensor on the tank. Until initial calibration is completed, the LED blinks red; after successful calibration, it blinks green.

In the Simarine app (BLE): select the tank → Settings → Tank Calibration. For each calibration point: enter the actual volume and tap Use Current Sensor Value to capture distance (or type it manually). Save and repeat — up to 100 points. You can edit or delete points later. Tank calibration defines the volume-vs-height curve; it is separate from initial setup.

Enter the actual volume (liters). Tap Use Current Sensor Value to capture distance, or type it manually.

Yes — up to 100 points (volume + captured sensor distance).

Yes — add or adjust points any time; a how-to video is in preparation.

Yes, but only if the tank height is entered manually. When using automatic tank height estimation, the bottom must be covered with liquid (≈1–2 cm is sufficient).

Pause at known increments (e.g. every 10–20%), enter the volume, then tap Use Current Sensor Value.

Yes — calibration points can be exported via the app.

Approximately 7 mm resolution with a typical 1 Hz update (STR1) and 0.5 Hz (STR2).

It measures to the top, but for liquid distances less than ~40 mm from the radar, the output may not reflect actual level.

Slosh filtering is applied inside the sensor, ensuring stable and reliable output.

Foam can weaken or scatter radar echoes; impact depends on thickness, consistency, and placement. In grey or waste water tanks, foam typically binds to dirt and collapses, so it's usually not a problem in real use.

Light condensation generally isn't a problem, but standing water or thick films on the lid can disturb the radar path. Keep the mounting area clean and dry; add drip or strain relief if condensation is persistent.

PGN 127505 (Fluid Level); level updates around 0.5 Hz.

All NMEA 2000-related configuration is modified in the app. The option appears automatically when connected to an STR2 device.

It is currently in the certification phase.

• Supply: 8–35 V DC (fuse per system standards).
• STR1 outputs: 0–190 Ω, 240–33 Ω, 0–5 V — all available simultaneously.
• STR2: NMEA 2000 backbone connection.
• Red → +8–35 V DC
• Black → GND
• Blue → COM
• White → 0–190 Ω
• Yellow → 240–33 Ω
• Green → 0–5 V
• Pin/terminal order is not specified — use the official wiring sheet if required.

Ensure the selected output matches the gauge (0–190 Ω / 240–33 Ω / 0–5 V). Re-run calibration if you changed ranges. Some gauges need a power cycle.

• Power/ground: verify stable 8–35 V DC and solid grounding.
• Mounting: ensure the sender is flat, firmly bonded, and no water is trapped between lid and sender; add strain relief so the cable can't tug the unit.
• Setup: if issues persist, repeat initial setup and recheck Tank Calibration points.

Verify 8–35 V DC supply and wiring to COM/ground. Ensure the green LED blinks and the app detects the device.