If you do not require as great a measurement range as the RM3-AR Test Unit provides, you might be interested in the:

CYL Probe with HM21 Hand Held Meter

Jandel CYL-RM3AR Four Point Probe System

General Purpose Portable Four Point Probing System for Measuring Sheet Resistance or Volume Resistivity

About the RM3-AR Test Unit

• The RM3-AR Test Unit is a specialty electronics instruments designed specifically for the four point probe meas-urement. It features high accuracy, an excellent range, and many features which simplify the four point probing measurement. The following are features of the RM3-AR Test Unit: The measurement range of the RM3-AR Test Unit is from 1 milliohm-per-square (10^-3) up to 5 x 10^8 ohms-per-square with 0.3% accuracy. The volume resistivity range is from 1 milliohm-cm (10^-3) up to 10^6 ohms-cm.
• The RM3-AR includes PC control software which can be used for data logging (storing data in the CSV format) and measurement conversion to ohms-per-square or ohms-cm.
• The RM3-AR reads-out directly in ohms-per-square (or toggle to millivolts) without requiring the use of the software or a PC.
• The RM3-AR has onboard non-volatile memory so that up to 50 measurements can be stored internally and then downloaded and saved all at one time using the software. Alternately, each measurement can be saved to a PC as it is made.
• The RM3-AR has an auto-range button that can be used to automatically determine the optimum input
  current for a given material without using the trial and error method.
• The RM3-AR has forward (FWD) and reverse (REV) buttons to reverse the direction of current flow. A
  common way to determine if a measurement is valid is to reverse the direction of current flow and then
  check to see if the forward and reverse voltage readings correlate well, i.e., the values should be similar,
  but with the reverse current voltage being a negative value. More about reversing the input current:
  reversing_current.pdf

About the Jandel Cylindrical Probe

The Jandel Cylindrical probe is built to a high level of mechanical accuracy as are all Jandel four point
probe heads. Specifications for radii, spacing, planarity, and spring load are verified by calibrated instruments
including a video inspection system, an optical interferometer, and an electronic force gauge. Each
probe tip is guided by upper and lower jeweled needle guides. Additional information about probe quality can be found in the Jandel probe head application notes.

Jandel Engineering Ltd. RM3-AR Test Unit Four Point Probe Measurement Electronics

The RM3-AR Test Unit reads out directly in ohms-per-square (or millivolts), and it includes a USB connection and PC software to save the data as either sheet resistance or as volume resistivity. Information regarding the PC software can be found here:

http://www.fourpointprobes.com/rm3ar_instructions.pdf

Cylindrical Probe with Small Nosepiece Shroud combined with the RM3-AR Test Unit*

*Inclues a 1 meter long cable

Small Shroud Installed on Cylindrical Probe Nosepiece

Cylindrical Probe Pressure Adjustment

The Cylindrical Probe has spring loads which are user adjustable within one of three ranges. The probe shown here has been factory set to 100 grams per tip, however, the user can increase the load to as high as 150 grams per tip or as low as 60 gram per tip by moving the red Teflon knob towards either the “H” for higher or towards the
“L” for lower.

Four-Point-Probes is a division of Bridge Technology. To request further information please call Bridge Technology at (480) 988-2256 or send e-mail to Larry Bridge at: sales@bridgetec.com