TB-3014
Page 3 of 7
DESCO WEST
- 3651 Walnut Avenue, Chino, CA 91710 • (909) 627-8178
DESCO EAST
- One Colgate Way, Canton, MA 02021-1407 • (781) 821-8370 • Website:
Surface resistance ohm values are expressed with a
mantissa and exponent or power of the number. For
example, if “8” is illuminated by its LED and the LCD
displays a mantissa of “7.14”, the measurement is 7.14 x
10E8 ohms or 714,000,000 ohms
If surface is over 10E12 ohms, the following will appear:
• “1____” on the LCD display indicate Overrange or that
the reading exceeds the display capabilities
C. Test Button:
This red button activates electrical power
to the Meter. The exponent or power of the measurement
is displayed immediately with LED illuminating number. If
“8” is illuminated, the measurement is in the 10
8
or 10E8
ohm range. To make a measurement in accordance
with ANSI/ESD S4.1, the button is to be depressed for
10-20 seconds for the unit to make numerous readings
and calculations. (Testing in accordance with ANSI/
ESD S4.1-1997 requires 15 seconds of electrification; in
contrast, most analog type meters display measurements
instantaneously.) The LCD will display temperature (F),
then temperature (C), then relative humidity, and then the
surface resistance mantissa.
During the entire period, if the measurement is stable,
the surface resistance exponent will be displayed by LED
illuminating number.
D. Override Test Range Voltage Button:
When in the “up”
position, the Meter will automatically switch to the correct
voltage for the resistance range. LED will illuminate noting
selected voltage. Material 10E5
ohms or less should be
measured at 10 volts. Material 10E6 or greater ohms
should be tested at 100 volts. The button is a switch,
which if depressed will override the automatic voltage
selection and test will be performed at 10 volts regardless of
resistance level.
E. Jacks:
One end of Test Leads has 3.5mm plug (fits
Meter left jack). The 3.5mm plug is shielded (identified by
insulated tip and barrel black lead) - see Rtg test procedure:
Per ANSI/ESD S4.1 “The sensing lead of the resistance
meter shall be connected to groundable point.” One end of
Test Lead has a standard banana plug (fits 5# Electrode
jack).
F. AA Battery Compartment.
G. Resistivity Parallel Attachment with Electrodes.
(optional Item number
)
Cleaning
Per ANSI/ESD S4.1 “Clean the electrodes with a minimum
70% isopropanol-water solu tion.” Make sure the 5 pound
electrodes’ conductive pads are dry prior to use.
See specific product test standard for test lab specimen
cleaning instructions. Per ANSI/ESD S4.1 Worksurfaces
“The test specimens and electrodes shall be cleaned twice
with a minimum 70% isopropanol-water solution using a
clean, low-linting cloth each time.” (Note: then conditioned
for 72 hours, minimum).
For compliance verification testing, do not clean surfaces.
However, if any measurements lie outside acceptable
range, then clean the material’s surface and re-test.
NOTE: For worksurfaces, use Desco Item#
Reztore™ Antistatic Surface and Mat Cleaner or other
silicone-free ESD cleaner. Be sure the surface is dry before
testing.
Periodic maintenance
- The area surrounding the cable
jacks at the top end of the meter should be wiped with a
clean cloth moistened with alcohol to remove skin oils that
will accumulate and affect the accuracy at high resistances.
The frequency of cleaning will depend on usage; once a
month would be a good starting point. Other items that
should also be cleaned in this fashion are the cable jackets
and the resistivity attachment.
Power Requirements
The Meter is powered by two replaceable alkaline AA
batteries.
Battery Replacement
Depress buttons on both sides of bottom end cap of meter
housing. Remove exterior cap. The batteries are located
under the raised, black, rectangular cap. Insert small probe
or screwdriver into slot and pry cap up. Carefully replace
batteries with alkaline Type AA. Polarity must be correct
or damage may occur. Close battery door and re-install
bottom end cap on meter housing.
Test Procedure
General Guidelines:
• Use both 5 pound electrodes for Rtt
• Use one 5 pound electrode and one lead to groundable
point for Rtg (note: groundable points are usually snaps
installed on the material or workstation common point
ground)
• Use optional Resistivity Attachment (removing leads &
electrodes) for Resistivity measurements
• Ensure that item being measured is electrically isolated
(i.e. placed on an insulative surface) as Meter will
measure lowest resistance path
• Ensure that test leads are separated as a best practice
• When using 5 pound electrodes:
• Place no closer than 2” from edge of surface being
measured
• Place no closer than 3” to any groundable point
• Place 5 pound electrodes about 10” apart for Rtt of
worksurface and 3’ for floor
• Preferred placements include: most commonly used
surface portion, most worn, center, and furthest from
groundable point.
• For Rtg, connect the sensing lead with shielded plug
to groundable point
• If surface has sections (like floor tiles or garment panels),
for Rtt place a 5 pound electrodes on different sections
• Clean material’s surface for Test Lab, but do not initially
clean surface for installed products (clean and retest if
failure occurs).
© 2013 DESCO INDUSTRIES INC.
Employee Owned
