RH top-extenders are used for in-situ concrete moisture testing, when the measuring depth for the RH probe is less than 1.5″.
When the sleeves are cut shorter (see ASTM F2170 for required measuring depth), the RH probes could be either too close to the surface or sticking out above the sleeve. The blue and red caps do not fit anymore, then the top-extenders have to be used to seal the opening. They fit tightly into the sleeves and cover the RH probes.
The top-extender consists of two pieces, a blue hood and a black cylinder. The blue hood is removed to obtain a measurement and has to be put back into place after the measurement is done. The concrete cable can be used in the black cylinder, the same way as it is used in the sleeve.
The RH top-extenders stick out 1 3/8″ above the sleeves. If the sleeves have to be cut 3/4″ or shorter, then two of the black cylinders can be stacked into each-other to cover the RH BluePeg probe. Order 2 top-extenders per sleeve. The black cylinders can be stacked and one of the blue cap hoods not used.
The RH cable with sleeve-cover (#RH-CB) can be used instead of the top-extenders. With the top extenders, you have to remove the blue hood every time you take a measurement. With the RH-CB cable, the open cable is connected whenever readings have to be obtained. The sleeve, RH probe, blue hood and cable connection are throughout the test series undisturbed. The RH-CB cable has to be used to monitor RH probes in the sleeve with any of the data loggers.
Lignomat offers three moisture meters and two data loggers for RH measurements:
If you need longer sleeves than 1.8″, click here to order longer sleeves.
For more information please contact Customer Service at 1-800-227-2105.
Lignomat USA Ltd, 14345 NE Morris Ct., Portland OR 97230, USA,
Email: sales@Lignomat.com, www.Lignomat.com