Resipod fully integrated surface resistivity instrument

Resipod fully integrated surface resistivity instrument

Resipod fully integrated surface resistivity instrument
for corrosion assessment
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The CN700 Resipod is a fully integrated 4-point Wenner probe, designed to measure the electrical resistivity of concrete in a completely non-destructive test. It is the most accurate instrument available, extremely fast and stable and packaged in a robust, waterproof housing designed to operate in a demanding site environment.
Complies with the proposed AASHTO standard for a surface resistivity test for estimating hardened concrete permeability.
Surface resistivity measurement provides extremely useful information about the state of a concrete structure. Not only has it been proven to be directly linked to the likelihood of corrosion and the corrosion rate, recent studies have shown that there is a direct correlation between resistivity and chloride diffusion rate and even to determination of early compressive strength. This makes it one of the most versatile NDT methods for concrete.


  • Simple to use
  • Fully integrated surface resistivity instrument
  • Highest resolution available for a surface resistivity instrument
  • Hold, save and delete function, with onboard memory
  • USB connection and dedicated PC software
  • Designed to float (waterproof)


  • Surface resistivity test on standard cylinders 4" x 8", 100mm x 200mm or 6" x 12", 150mm x 300mm) with a maximum aggregate size of 1.5", 38mm. Fixed probe spacing (1.5", 38mm)
  • Correction factor for probe spacing
  • Surface resistivity mapping on site for: estimation of likelihood of corrosion, corrosion rate & implementation of cathodic protection systems

Resipod Surface Resistivity (SR) Method

In 2011 the American Association of State Highway and Transportation Officials (AASHTO) became the first standards body to define permeability classes based on resistivity measurements (TP95-11 Standard Method of Test for Surface Resistivity Indication of Concrete’s Ability to Resist Chloride Ion Penetration).
Since that time this test has established itself as a simple, economical alternative to the ASTM C 1202 Rapid Chloride Permeability test with several clear advantages:

  • Much faster to perform
  • No sample preparation necessary
  • Test can be repeated at different ages e.g. 28 days, 56 days
  • The same cylinder can be used for compressive strength testing

CN700 Resipod with 1.5” (38mm) probe spacing is fully compliant with the above mentioned standard.


All measurements saved on the Resipod may be downloaded for analysis with the software included with all
models. User defined correction parameters may also be defined in the software and uploaded to Resipod.


Resolution (nominal current 200µA) ±0.2 kΩcm or ±1% (whichever is greater)
Resolution (nominal current 50µA) ±0.3 kΩcm or ±2% (whichever is greater)
Resolution (nominal current <50µA) ±2 kΩcm or ±5% (whichever is greater)
Frequency 40 Hz
Memory Non volatile, ca. 500 measured values
Power Supply >50 hours autonomy
Charger connection USB type B, (5V, 100mA)
Dimensions 197 x 53 x 69.7 mm (7.8 x 2.1 x 2.7 inch)
Weight 318 g (11.2 oz)
Operating temperature 0° to 50°C (32° to 122°F)
Storage temperature -10° to 70°C (14° to 158°F)

CN700 supplied as:

Resipod, 50mm probe spacing, test strip, foam contact pads, charger with USB cable,software, carrying strap, documentation and case.

Standard warranty

Electronic portion of the instrument: 24 months
Mechanical portion of the instrument: 6 months