No breaking out or drilling of concrete required, as it is a surface test
Simple and accurate testing by sponge insert type sensor
A reference block ensures the reliability of test result
Display hold function
Automatic power off to save battery
4 hours operation by rechargeable batteries
Low battery status display
Rugged aluminum case & carrying pouch
Easy to carry in a rugged aluminium bag

The corrosion of steel in concrete is an electro-chemical process which creates a current flow causing metal to dissolve so that it is possible to assess the probability of reinforcement corrosion by evaluating the electrical resistance of the concrete. The factor is measured in terms of resistivity and expressed in Ohm.
The resistivity of concrete varies over a complete structure due to a variety of changing site conditions from day to day so that other methods, like half-cell potential or impact testing, should be combined to ensure the data. Generally, the probability of the steel corrosion increases, the concrete resistivity deceases.
One of the practical problem of concrete resisitivity testing is to ensure the good electrical contact between the electrodes and concrete surface. In Resitest-400, Sponge insert type sensor is used for good electrical contact. Resitest-400 is supplied with Wenner sensor,carrying pouch, reference block, connection cable, AC adaptor, sensor cleaning bottle, insert sponge, aluminium bag and instruction manual.
Resitest-400 electrical circuit for measuring concrete resistivity
Resitest-400 Kit
  Resitest-400 main body
Wenner sensor
Insert sponge (8 pcs)
Connection cable
Reference Block
Sensor cleaning Bottle
Carrying pouch
AC adaptor for rechargeable battery
Aluminium carrying bag
Instruction manual
Specifications of Resitest-400
  Measuring Method: Concrete resistivity testing by Wenner array sensor (50mm spacing)
Measuring Range: 0 2,000 k
Display: 3 1/2 digit LCD
Resolution: 1 k
Display Stability: 1 k
Input impedance: 100 M
Automatic Shut-Off: After 5 minutes without use
Hold Function: Hold the display
Display Function: Low Battery and Hold status
Power: 12V (1.5V x 6 rechargeable batteries)
Battery Life: About 5 hours
Operating Temperature: -10~50
Size: 1638941mm
Weight: 750 grams (main body including battery)
Warranty: one year

 R-1 type
W-2 type  
HM-3 type  

Concrete Resistivity Inspection. using RT-4000

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