3-prong VWC sensor for substrate-driven irrigation and crop steering across coir, rockwool, and soil.
The TrolMaster WCS-3 Water Content Sensor 3 is a 3-prong Volumetric Water Content (VWC) sensor that measures substrate moisture percentage in real time — the foundational data point for precision dry-back management and automated crop steering. Includes splitter cable set and integrates natively with TrolMaster's Aqua-X, Hydro-X Pro, and Tent-X control systems.
The TrolMaster WCS-3 is a 3-prong Volumetric Water Content sensor purpose-built to measure the moisture level — expressed as a percentage — inside a grow medium. The three stainless steel prongs insert directly into the substrate (coir, rockwool, or soil), where the sensor continuously reads the VWC% at that point in the root zone.
Each WCS-3 ships with a splitter cable set, giving you the connectivity hardware needed to chain multiple sensors in a single run. A compact, ultra-slim housing keeps the sensor low-profile in the container or slab, and a built-in LCD display activates on tap or movement so you can read the live VWC% directly at the sensor without pulling up a dashboard.
The WCS-3 reading simultaneously feeds the connected TrolMaster controller and is visible in real time via the free TM+ Pro smartphone app. The app also stores historical VWC data graphs and pushes mobile alerts when readings breach your programmed high or low setpoints — critical for catching irrigation failures or runaway dry-backs without being on the floor.
The WCS-3 is the right sensor for licensed cannabis and hemp operators who are running or building out substrate-based crop steering programs. If your cultivation team is managing target VWC windows during vegetative and flower stages — adjusting dry-back depth and irrigation shot timing by phase — you need real substrate data to execute that protocol. Timer-based irrigation can't respond to actual transpiration rates; VWC-triggered automation can.
The sensor fits operations on coco coir and rockwool, which are the dominant substrates in data-driven commercial cannabis production. It also reads soil for operations running amended or living-soil programs where moisture tracking matters. Whether you're running a single room or a multi-zone facility, the WCS-3's daisy-chain architecture means you can scale sensor density alongside canopy without swapping hardware.
Cultivators already on TrolMaster's Aqua-X or Hydro-X Pro platform will find the WCS-3 is the native substrate sensor for those systems — it reports directly to the controller and participates in automated irrigation logic rather than acting as a standalone logger you have to interpret manually.
3-prong VWC measurement: stainless steel prongs insert into the grow medium for direct, continuous moisture readings expressed as percentage — the standard metric for substrate-based crop steering protocols.
Tap-to-wake LCD display: the built-in screen activates on contact or movement, showing the live WC% reading directly on the sensor body. No controller interface needed to spot-check a slab or pot during a walk.
Daisy-chain scalability with splitter cable: the included splitter cable set allows multiple WCS-3 units to share a single controller port. Depending on the controller, you can run up to 50 WCS-3 sensors on a single NFS-2 (Aqua-X Pro) or HCS-2 (Hydro-X Pro), 20 on the NFS-3 (Aqua-X Plus), 8 on the NFS-1 (Aqua-X), and 1 on the TCS-1 (Tent-X). This makes multi-container and multi-zone monitoring at scale practical without proportional cable complexity.
Mobile monitoring and alerts: via the free TM+ Pro app, VWC readings are visible live on a smartphone, historical graphs are stored for trend review, and push notifications fire when readings exceed programmed alarm limits — high or low.
In a substrate-driven irrigation setup, the WCS-3 is the sensor that closes the loop between your controller and what's actually happening at the root zone. Rather than running irrigation on a fixed timer, the Aqua-X and Hydro-X Pro controllers use the live VWC% readings from the WCS-3 to trigger irrigation events based on measured dry-back — water when the substrate reaches a target threshold, stop when field capacity is hit.
For a multi-table room, the standard deployment is one WCS-3 per representative container or slab per zone, capturing the moisture curve through a full light cycle. High-sensor-count configurations — where you're covering multiple strains, container sizes, or irrigation zones — take advantage of the 50-sensor maximum on the NFS-2 and HCS-2 to map moisture variation across the room and feed that data back into zone-specific irrigation logic.
The WCS-3 is also a calibration-required device: the sensor is zeroed to 0% (dry medium) and 100% (saturated medium) at installation. If the sensor is relocated to a different container, recalibration is recommended to maintain accuracy. Account for that in deployment planning — sensors placed at commissioning tend to stay in position through the run.
| SKU | WCS-3 |
| Manufacturer | TrolMaster |
| Sensor Type | 3-prong Volumetric Water Content (VWC) |
| Measurement Output | Water Content % (VWC%) |
| Compatible Grow Media | Coir (coco), Rockwool, Soil |
| Compatible Controllers | Aqua-X NFS-1, Aqua-X Plus NFS-3, Aqua-X Pro NFS-2, Hydro-X Pro HCS-2, Tent-X TCS-1 |
| Max Sensors per Controller | 50 (NFS-2 / HCS-2) | 20 (NFS-3) | 8 (NFS-1) | 1 (TCS-1) |
| Display | Built-in LCD (tap/motion-activated, shows live VWC%) |
| App Connectivity | TrolMaster TM+ Pro (iOS/Android) — live data, historical graphs, push alerts |
| Included Accessories | Splitter cable set |
The WCS-3 measures Volumetric Water Content (VWC%) only — it is a single-parameter sensor. It does not measure electrical conductivity (EC) or substrate temperature. If you need all three parameters (VWC, EC, and temperature) from a single probe, TrolMaster offers the WCS-2 and the newer WCS-9 substrate sensor set, which add EC and temperature to the measurement stack. The WCS-3 is the purpose-built VWC-only option in the lineup — simpler, scalable to higher sensor counts, and well-suited for operations where moisture management is the primary automation input.
The minimum practical deployment is one WCS-3 per irrigation zone — placed in a representative container or slab that reflects the moisture behavior of that zone. Larger rooms with multiple strains, container sizes, or distinct irrigation circuits benefit from one sensor per zone at minimum, and some operators run one per row or table to catch variation. The hardware ceiling depends on your controller: up to 50 sensors on the Aqua-X Pro (NFS-2) or Hydro-X Pro (HCS-2), 20 on the Aqua-X Plus (NFS-3), and 8 on the Aqua-X (NFS-1).
The WCS-3 is compatible with the Hydro-X Pro (HCS-2) but is not designed for the original Hydro-X (HCS-1). If you are running an older HCS-1, confirm compatibility with your controller firmware version before ordering — or contact us to clarify the right sensor for your specific TrolMaster setup.
Yes, calibration is required and is a two-point process: you calibrate the sensor at 0% (fully dry medium) and 100% (fully saturated medium) at initial installation. Once calibrated to your specific substrate and nutrient solution, the sensor provides continuous, reliable readings through the run. If the sensor is moved to a different container or slab, TrolMaster recommends recalibrating to account for differences in medium density and pore structure. Plan sensor placement before commissioning so you can calibrate in place and leave the sensors positioned through the full crop cycle.
Yes. The WCS-3 reading feeds the TrolMaster controller, which connects to the free TM+ Pro app (iOS and Android). From the app you can view live VWC% readings, review historical moisture graphs to analyze dry-back curves over time, and receive push notifications if a reading exceeds your programmed high or low alarm setpoints. This remote visibility is particularly useful for catching irrigation system failures or unexpected overnight dry-back events before they cause crop stress.
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