A factual side-by-side comparison. Sensytec makes a Bluetooth sensor for field crews and a long-range two-signal sensor for plants, plus match-cure hardware and plant QC software. Converge is a UK-headquartered platform company whose sensors feed ConcreteDNA, where strength is calculated from temperature history. Here is where each one fits.
| Capability | Sensytec SensyRoc II | Sensytec SensyCast | Converge |
|---|---|---|---|
| Built for | Field crews, GCs, jobsite pours | Plants, mass pours, multi-pour producers | Sensors across the Signal, Helix and Mesh families, reporting into the ConcreteDNA platform |
| Signals measured | Temperature + electrical resistivity | Temperature + electrical resistivity | Concrete temperature, with strength derived in software by the maturity method. Signal Probe documentation also includes relative humidity |
| Electrical resistivity | Yes, measured in place | Yes, measured in place | Converge publishes no electrical resistivity capability |
| Getting data off the sensor | Bluetooth LE to a free iOS/Android app, standard BLE range at the pour | ~1 mile (1.6 km) sub-GHz to a gateway, keeps transmitting after burial | Varies by product. Signal (Bluetooth) up to 15 m line of sight, 8 m when submerged by up to 100 mm of concrete; Signal Long Range up to 300 m; Helix up to 1.5 miles node-to-hub; Mesh Hub has cellular (GSM/GPRS/EDGE, HSUPA/HSDPA/UMTS) |
| Hardware recovered after the pour | Yes, reusable body, replaceable probes | Yes, reusable logger | Mixed by product. Converge: “Signal Long Range is a single-use embedded sensor, designed to stay permanently in the concrete.” Helix is reusable, its Node stays outside the pour and detaches from an embedded Thermal Tail probe. Mesh is also marketed as reusable |
| Battery | Non-rechargeable, 1 year | Rechargeable, 3 years | Not compared |
| Match-cure system | SensyCure, tracks the bed within an average of 0.79°F | No match-curing hardware in their published lineup, no chamber, controller or heater. Their product named “Cure” is a monitoring and prediction app | |
| Plant QC and compliance | SensyHub QC: PCI MNL-116/117, NPCA QCM-001, state DOT workflows, batch logs, break logs, NCRs, audit-ready exports | Data Hub is aligned to BS EN 206, a European standard. We found no PCI, NPCA, AASHTO or state DOT plant-certification workflow in their published product documentation | |
| Precast / prestressed offering | Core market, incl. transfer strength and detensioning | FieldAtlas, a logistics and element-tracking platform (factory, transport, yard, site) offered on “Request Early Access”. Its published feature set does not include QC, batch records, or demould/detension decision support | |
| ASTM C1074 | Yes | Yes | Their Helix page states the app is developed in “Compliance with ASTM C1074 Standards” |
| AASHTO T-358 / ASTM C1876 | Yes (resistivity) | Yes (resistivity) | Not published |
| Headquarters | Houston, Texas, USA | London, United Kingdom (founded 2014) | |
Both companies use the maturity method, so this is not a knock on the math. It is a question of how many inputs the math has. Converge publishes no electrical resistivity capability. On their current sensor pages, the stated measurement is concrete temperature, with strength derived in software by the maturity method. SensyCast measures electrical resistivity in place alongside temperature, per ASTM C1876 and AASHTO T-358. That second signal is independent of the maturity curve, so it flags calibration drift, mix changes, and unfamiliar admixture behavior instead of inheriting them, and at later ages it tracks with chloride-ion penetration resistance as a durability indicator.
For prestress release and PCI-certified production, the accuracy of your companion cylinders decides when you detension. SensyCure holds those cylinders within an average of 0.79°F of the bed for the full cure, and our controlled two-day trial shows what happens without it: a legacy system over-cured cylinders by up to 27.4°F. Converge's published lineup includes no match-curing hardware, no chamber, controller or heater. They do sell a product named Cure, but it is a monitoring and prediction app, not a match-curing system. That is a category difference, not a spec difference.
Converge's compliance module, Data Hub, is aligned to BS EN 206, a European standard, which makes sense for a company built in and for that market. If your plant is audited to PCI MNL-116 or MNL-117, or NPCA QCM-001, or a state DOT certification program, that alignment does not carry over. We found no PCI, NPCA, AASHTO or state DOT plant-certification workflow in Converge's published product documentation. The SensyHub QC Module ships those checklist modes directly, with batch logs, break logs, NCRs, sticker workflow, and audit-ready exports. For general contractors it does the jobsite equivalent, generating strength reports and submittals from the same data instead of assembling them in a spreadsheet.
Converge's precast-facing product is FieldAtlas, a logistics and element-tracking platform covering factory, transport, yard, and site, currently offered on a “Request Early Access” basis. Its published feature set does not include QC, batch records, or demould and detension decision support. Knowing where a beam is and knowing whether it can be released are different problems. Precast and prestressed production is Sensytec's core market, and the stack is built around the second question: bed monitoring, match-cure, transfer strength, detensioning, then the audit export.
SensyRoc II and SensyCast both report into SensyHub. Start with a phone on one jobsite, add plant beds and a gateway later, and the history, mix calibrations, and reports stay in one place. Choosing the entry tier does not mean choosing a vendor you have to leave when the work gets bigger.
Sensytec is headquartered in Houston, Texas, and the hardware is made in the USA. For DOT work and public projects that touch Buy America provisions, and for plants that want same-time-zone support and US data residency, that shortens conversations that would otherwise involve a supplier headquartered in London.
Converge is a credible, well-funded platform company, building since 2014, and there are real reasons to choose them. We would rather say them than have you find out later:
What we would push back on is the assumption that you have to pick a platform on range and dashboards alone. The decisions that cost money in a precast plant, when to detension and when to ship, rest on match-cure accuracy and on QC records an auditor will accept. Those are the two places we are not comparing spec sheets, because there is nothing published to compare against.
Yes. SensyRoc II is a Bluetooth LE sensor with a free iOS and Android app, built for the same walk-up-and-read workflow, with a one-year battery and a sensor body that is recovered and reused with replaceable probes. You do not have to buy the plant-scale tier to get the simple one.
Where the stack ends. Converge sells sensors and the ConcreteDNA platform that interprets them. Sensytec sells a Bluetooth tier and a long-range two-signal tier, plus match-cure hardware and plant QC software, so the same vendor covers a one-off jobsite pour and a PCI-certified plant.
Converge publishes no electrical resistivity capability. On their current sensor pages, the stated measurement is concrete temperature, with strength derived in software by the maturity method. SensyCast measures electrical resistivity in place, alongside temperature, per AASHTO T-358 and ASTM C1876.
It depends which one. Converge states that “Signal Long Range is a single-use embedded sensor, designed to stay permanently in the concrete.” Helix is reusable, its Node stays outside the pour and detaches from an embedded Thermal Tail probe, and Mesh is also marketed as reusable. Both Sensytec sensors are recovered and reused, SensyRoc II as a body with replaceable probes and SensyCast as a logger that cycles for years.
Converge is strong here. They list Signal Bluetooth at up to 15 m line of sight and 8 m when submerged by up to 100 mm of concrete, Signal Long Range at up to 300 m, and Helix at up to 1.5 miles node-to-hub, with cellular on the Mesh Hub. SensyRoc II is Bluetooth, for crews at the pour. SensyCast reaches a gateway from roughly a mile (1.6 km) on sub-GHz and keeps transmitting after burial. If range is your only criterion, compare Helix against SensyCast directly.
Their published lineup includes no match-curing hardware, no chamber, controller or heater. They do sell a product named Cure, but it is a monitoring and prediction app, not a match-curing system. Sensytec's SensyCure holds companion cylinders within an average of 0.79°F of the bed and pairs natively with SensyCast and SensyHub, which is what transfer-strength and detensioning decisions rest on.
Not the method. Converge's Helix page states the app is developed in “Compliance with ASTM C1074 Standards”, and Sensytec implements the same maturity method on both tiers. Both require a mix-specific calibration before use, and accuracy comes from that calibration rather than the brand on the sensor. What differs is what sits around the method: a second measured signal on SensyCast, match-cure hardware, and the QC records.
Sensytec, and mostly for reasons that sit above the sensor. Converge's precast-facing product, FieldAtlas, is a logistics and element-tracking platform offered on “Request Early Access”, and its published feature set does not include QC, batch records, or demould and detension decision support. Their compliance module is aligned to BS EN 206, a European standard, and we found no PCI, NPCA, AASHTO or state DOT plant-certification workflow in their published documentation. Precast and prestressed is Sensytec's core market, from bed monitoring through match-cure to PCI and NPCA audit exports.
Tell us how you pour and we will tell you which tier fits: SensyRoc II on a phone, or SensyCast with resistivity and a mile of range. Match-cure and PCI / NPCA / DOT QC included in the conversation. Made in the USA.
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