Temperature String

A temperature string is essentially a cable with multiple digital or analog temperature sensors fixed at predetermined intervals, allowing continuous vertical or horizontal profiling. It’s used in groundwater studies, permafrost monitoring, concrete curing, and tailings dams. Kingmach’s approach is to configure each string around the project’s physical constraints and data resolution needs, rather than forcing off-the-shelf spacing. Sensor spacing can be uniform or varied—closer near the surface where gradients are steeper, wider at depth. Typical sensor types include NTC thermistors or digital sensors like DS18B20, depending on accuracy requirements and cable length. The cable itself is a key differentiator: we use polyurethane or polyethylene jackets with Kevlar strength members, permitting direct burial or suspension in wells without conduit. For groundwater wells, the diameter can be as small as 6 mm to minimize flow disturbance. For harsh environments, stainless steel encapsulation is an option. Kingmach manufactures these strings in-house, so lead time for custom designs is usually 2–3 weeks. Each string is pressure-tested to simulate submersion depth before shipping, and we provide calibration certificates for the sensors. While we don’t publish fixed specifications (every order is different), a recent 50-point string for a tailings dam monitoring project operated reliably at 60 m depth and -20°C. This flexibility and field focus is what makes our temperature strings a practical choice for geotechnical instrumentation projects.