Frequently Asked Questions

CONTEMP tracks concrete temperature on every pour and estimates in-place strength with the maturity method of ASTM C1074, so you can decide when formwork can come off or a slab can take load without waiting on cylinder breaks. It has two parts: the CONTEMP logger (part number CONTMP), a battery-powered logger with an ambient sensor and two embedded sensors, and the CONTEMP dashboard at dashboard.contemp.live for readings, alarms, pours and reports.

CONTEMP is a brand of LoggerFlex Smart Devices Ltd. in Vancouver, Canada, which makes, invoices and supports CONTEMP products. CONTEMP is a registered trademark.

CONTEMP is “Hybrid”: it has built-in cellular and WiFi. Cellular works out of the box, with no gateway and no site network. Where there is no cellular coverage (for example a remote site with only Starlink, a tunnel or a mine), connect the logger to WiFi. When a WiFi network is set up, the logger always uses WiFi first, automatically.

Register the logger in your CONTEMP account first, then long-press the SYNC button to start setup. The logger opens its own setup hotspot: join it from a phone or laptop, pick your 2.4 GHz network and enter the password. WPA2-Personal, WPA3-Personal and WPA2/WPA3 mixed mode work; WPA2-Enterprise, WPA3-Enterprise and captive-portal networks do not. The logger gets its IP address from the router automatically (DHCP); a fixed IP address cannot be set.

Three temperatures: the logger’s own ambient sensor and two embedded sensors on plug-in leads, one white (SENWHT) and one black (SENBLK). Only the two embedded sensors are used for maturity; ambient air is shown for context, because air temperature is not concrete temperature. Put one sensor where strength must be certified (usually deep in the section, which runs warmest) and the other near the exposed face (coldest and slowest to cure). Formwork comes off on the colder one, so that is normally the primary sensor.

The embedded sensors are sacrificial: they are cast into the concrete and stay there, so every pour needs new sensors. The system works only with original CONTEMP sensors from CONTEMP or its distributors. If a sensor from another source is plugged in, the logger blinks red and blue: the sensor is not authorized, and the system will not work until an original sensor is fitted.

Each sensor has a 1.5 m (4.9 ft) lead. With CONTEMP extensions (EXTBLK for the black sensor, EXTWHT for the white one) a leg can run up to 16.5 m (54 ft) in total, sensor lead included, which is up to 15 m (49 ft) of extension. Keep the two legs within 3 m (10 ft) of each other in length.

Item	Part number
CONTEMP logger	CONTMP
Black sensor	SENBLK
White sensor	SENWHT
Black sensor extension	EXTBLK
White sensor extension	EXTWHT

Sensors and extensions are sold one by one.

An accessory pack holds up to 4 sensors or up to 4 extensions, for example 2 black and 2 white sensors. It also has 4 × AA alkaline batteries, a permanent marker and plastic tags to name the sensors. The CONTEMP logger itself is not part of the pack.

By 4 × AA batteries: alkaline cells (what we ship) or Energizer Ultimate Lithium. Changing them needs no tools: undo the two stainless-steel D-shaped screws at the bottom by hand, open the enclosure gently, replace the batteries and refit the screws. We do not give a battery-life figure per pour, because it depends on how long the pour runs, the reporting interval, the signal and the temperature. Spare batteries come in every accessory pack, so they can always be replaced on site.

No. CONTEMP loggers have no subscription at all: full access to the CONTEMP dashboard is included for 10 years, and a logger is never billed and never stopped for non-payment. Email alerts are free; text-message alerts use the logger’s prepaid alert credit.

CONTEMP is sold through distributors, including Gilson and Solid EDGE. Suggested retail prices (MSRP, CAD, as of October 2026): CONTEMP logger (CONTMP) $299; each sensor (SENBLK or SENWHT) $49; each sensor extension (EXTBLK or EXTWHT) $49. Distributors set their own prices. For a quote or a distributor near you, email [email protected].

In the Concrete section of the dashboard you create a calibration formula for each mix (its strength-maturity curve) and a project for each pour. CONTEMP adds up the temperature history of each embedded sensor into maturity, using Nurse-Saul (temperature-time factor) or Arrhenius (equivalent age), and reads the estimated strength off your curve. The pour is complete when every sensor that counts toward completion reaches the target strength or maturity. Learn more about the maturity method →

Both functions of ASTM C1074: Nurse-Saul, with a datum temperature (ASTM C1074 recommends 0 °C (32 °F) when none has been determined by test; −10 °C (14 °F) is the classic alternative), and Arrhenius, with an activation parameter and a reference temperature (23 °C (73 °F) by default). The method is locked once a formula is saved, because the measured points are in that method’s units.

Yes. A strength estimate is only as good as the mix-specific curve built from specimen breaks. Enter the maturity and strength pairs from your lab breaks and choose straight lines between points, a logarithmic fit (3 or more points) or a hyperbolic fit (4 or more points); the curve and its R² are previewed as you type. Once a pour uses a formula, its numbers are locked, so a published pour record cannot be quietly restated. Follow your project specification for acceptance testing. Learn about calibration curves →

It keeps recording and uploads the stored readings when the connection returns. If its memory fills, it pauses recording until the data has uploaded. In a pour, a silence longer than the formula’s “longest gap to bridge” (180 minutes by default) earns no curing credit, and the project shows how many intervals were skipped.

• Min/Max temperature alarms on each channel.
• Differential alarms on the gap between the white and black sensors, or between either sensor and ambient, for example core-to-surface limits on mass concrete. You set the gap; the alarm fires when it is exceeded.

Alarms are sent by email and text message; repeat notifications are limited to one per hour per logger.

CONTEMP sends a completion notice once per pour: an email to the logger’s owner and everyone it is shared with (except Silent Viewers), and a text message to the project owner’s verified phone number if the logger has alert credit.

• PDF pour record for each finished pour: the pour’s particulars, each sensor’s formula, the calibration curve, a day-by-day table, the site photo and temperature, maturity and strength charts, on the letterhead of the pour’s owner.
• Excel file with the summary and every raw reading.
• Logger reports for any logger: all readings, hourly and daily min/max/average reports, and several sensors combined in one report.

Pour reports always cover the whole pour and are issued only once it is finished, because a strength that is still climbing is not a result.

Yes. Each pour is its own project with its own loggers and formulas, and the dashboard lists all of them with their status and progress.

Share a logger with your whole team at no extra cost. Each person has their own free account and notification settings, and you choose a role:

• Editor — changes settings and thresholds and acknowledges alarms.
• Viewer — sees data and reports and receives alarms.
• Silent Viewer — sees data but receives no alarms.
• Service & Maintenance — for service partners.

Only the logger’s owner can share it.

Yes. If a logger is already registered to another account, you can request a transfer; the current owner is notified and approves it.

Sign in at dashboard.contemp.live, then register the logger by scanning its QR code or entering its serial number and DUID. The registration wizard then walks you through naming it, choosing °C or °F and setting alarms.

Every setting change, alarm and upload is recorded in the logger’s tamper-proof activity log, which you can download as a PDF. Pour reports are generated on demand and streamed to your browser; nothing is stored on a public link.

Yes. The logger is IP67 (dust-tight and protected against temporary immersion) and has been tested down to −36 °C (−33 °F) with Energizer Ultimate Lithium AA batteries.

A two-year limited warranty against manufacturing defects from the purchase (invoice) date, the same as LoggerFlex hardware. The embedded sensors are sacrificial and stay in the concrete, so plan new sensors for every pour. Opening the logger case, physical damage, water damage and repairs by anyone we have not authorized are not covered.

Yes. CONTEMP is an open platform, and plenty of customers buy the hardware and run everything else in the software their team already uses. Webhooks post to an address of yours as events happen — new readings, temperature alarms, and pours reaching their target — and a documented REST API serves readings, pour status, maturity and estimated strength whenever your system asks for it. The documentation is not published on this site: contact us and we will send it to your team so they can scope the work before you buy anything. More about integrations →

Yes — the dashboard has been rebuilt from the ground up. It takes fewer steps to get from signing in to watching a live pour, setting up a logger, its sensors, a calibration formula and a pour is one guided flow, and there is AI help built in, so you can ask a question in plain language about your pours, alarms or setup instead of searching a manual. Same account, same hardware, same address: dashboard.contemp.live.

Create an account or sign in at dashboard.contemp.live and register your loggers. For questions, a quote or a distributor near you, email [email protected] or use the contact form. Support hours: Monday to Friday, 9:00 to 17:00 Pacific time.