TB-2024
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Figure 8. Clean before testing.
Cleaning
Work surfaces or materials to be tested should be cleaned
prior to testing to ensure that surface dirt and contamination
do not affect the test results. Periodically clean the built-in
parallel electrodes and the two 5 lb. electrode conductive
rubber probe surfaces. Use solvent-free and silicone-free
cleaners. We recommend using Desco Reztore™ anti-static
surface and mat cleaner (item 10435). Be sure the surface
is dry before testing.
Power Requirements
The meter is powered by a rechargable 9 volt
Nickel/Cadium battery or a special AC to DC adapter. The
adapter is also used to recharge the 9 volt battery.
Surface Resistance Measurements (RTT)
Complies with ESD S4.1
Point to point surface resistance measurements are made
using the meter along with both of the 5 pound electrodes.
This test will determine the resistance between two points,
independent of a groundable point. To perform surface
resistance tests you must first determine what test
procedure you will be using. The test procedure will help
you to determine proper preparation of the material to be
tested and the spacing of the weights. Once testing
parameters are determined you can proceed with the
following instructions:
A. Connect the test leads to the meter by inserting the
banana termination end of a test lead into the 5 lb.
electrode and the 2.5 mm mini phone plug end into the
megohmmeter.
B. Place both electrodes on the material at positions
determined by the procedure selected. Set the meter to the
required test voltage determined by the test procedure and
the resistance of the material. Conductive material 10
4
ohms or less is usually tested at 10 volts. Dissipative
material is usually tested at 100 volts. If material to be
tested is unknown, it is recommended to first test at 10
volts.
C. Press and hold the red test button for 10-20 seconds
(the unit will be making numerous measurements and
calculations.) The measured resistance value will appear on
the display. This reading is expressed in ohms. You may
want to record the temperature, humidity and test voltage.
Figure 9. Setting up for RTT testing.
Surface-to-Ground Measurements (RTG)
Complies with ESD S4.1
The Surface-to-Ground readings will measure the surface
resistance between selected locations on a work surface
and a groundable point or points. Ground points are usually
in the form of snaps installed on the material so that the
material can be grounded via ground cords. The charge
dissipation rate of all ESD protective materials is related
directly to electrical resistance to ground. When making
Surface-to-Ground measurements, follow this prodedure:
A. Connect one of the 5 pound electrodes to the
megohmmeter using one of the test leads.
Figure 10. Setting up for RTG testing.
B. Using the other lead, connect one end to the
megohmmeter. Insert the grounding clip included with the
test clip onto the banana plug on the other end of the lead.
Now, connect the grounding clip to the groundable point on
the surface to be tested.
DESCO WEST
- 3651 Walnut Avenue, Chino, CA 91710 • (909) 627-8178 • Fax (909) 627-7449
DESCO EAST
- 90 Hudson Road, Canton, MA 02021-1407 • (781) 821-8370 • Fax (781) 575-0172 • Web Site: http://www.desco.com
