TB-6520
Page 3 of 7
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 number 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
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. For example, if the LCD displays a mantissa of
“7.14”, and “8” is illuminates by its LED, the measurement is
7.14 x 10E8
ohms or 714,000,000 ohms.
During the entire period, surface resistance exponent will be
displayed by LED illuminating number.
D. Override Test Voltage Button:
When in the “up”
position, during resistance portion of test, 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 ohms or greater should be tested
at 100 volts. The button is a switch, which if depressed
will override 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 standard banana plug (fits 5#
Electrode jack).
F. AA Battery Compartment.
G. Resistivity Parallel Electrodes Attachment.
(optional Item number
)
Cleaning
Per ANSI/ESD S4.1 “Clean the electrodes with a minimum
70% isopropanol-water solu tion.” Make sure 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 installed product periodic testing, do not clean surfaces.
However, if any measurements lie outside acceptable
range, then clean the surface and re-test (Note: for
worksurfaces, use an ESD cleaner not containing silicone).
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, if included.
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 cap, press on right edge of protruding
battery door, unlatching it, and swing door open. 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 black sensing lead to
equipment ground to groundable point for RTG
• 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 or Meter may
measure lower resistance path
• 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
worksurfaces and about 3' apart for RTT of flooring.
• Preferred placements include: most commonly used
surface portion, most worn, center, and furthest from
groundable point.
• If surface has sections (like floor tiles or garment panels),
for RTT place a 5 pound electrodes on different sections
• Clean surface for Test Lab, but do not initially clean
surface for installed products (if fails, clean and retest).
• Only use an approved ESD cleaner and allow to dry prior
to testing.
• Lay Meter on surface; holding in hand can cause
measurent distortions.
© 2010 DESCO INDUSTRIES INC.
Employee Owned
EMIT
- 3651 Walnut Avenue, Chino, CA 91710 • (909) 664-9980 • Fax (909) 627-7449 • Website:
