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TECHNICAL BULLETIN TB-7594
Portable Wrist Strap Tester
Installation, Operation and Maintenance
Installation
Open the tester’s battery compartment and install
the included 9 V battery. Use the included hook and
loop fastener strip to mount the tester to a wall or
worksurface.
NOTE: The low battery indicator flashes briefly every
time the unit is used. Replace the battery once the
indicator becomes constant during testing.
Operation
1. While wearing a wrist strap, plug the wrist cord
into the wrist strap jack located on the face of the
Portable Wrist Strap Tester.
2. Push down and hold the test switch until the test
results are displayed. Ensure that your finger also
makes contact with the metal ring around the
pushbutton when performing a test.
Figure 1. Vermason 225221 Portable Wrist Strap Tester
Description
Per EN 61340-5-1, test equipment is required to enact
the Compliance Verification Plan Requirement. Test
equipment shall be selected to make measurements of
appropriate properties of the technical requirements that
are incorporated into the ESD programme plan. The
Wrist Strap Tester can be used to fulfill
IEC 61340-4-6. “The typical verification frequency, used
by industry, for wrist cords is once per shift due to the
wrist cord’s importance to the success of the program
and the likelihood of failure.” (CLC/TR 61340-5-2
clause 4.3.3 Verification frequency). Being a portable
battery powered tool, it is perfect for small labs or
for a supervisor to spotcheck workers and/or ensure
compliance.
The Vermason 225221 Portable Wrist Strap Tester is a
battery operated “on demand” wrist strap tester. When
the wearer of a wrist strap plugs in their coiled cord and
touches the metallic surface of the Wrist Strap Tester,
a path for current flow is completed from the wearer’s
skin, through the wrist strap. This action will cause
the green “test good” LED to illuminate as long as the
resistance of the circuit path is between 750 kilohms
and 35 megohms.
DO NOT touch any other metal while performing
your test as this will affect your results.
3. A pass test result is indicated by illumination of the
green PASS LED. A fail low test result is indicated
by illumination of the red LOW LED. A fail high test
result is indicated by illumination of the red HIGH
LED.
If your ESD test fails, check your wrist strap and
ensure that it is being worn correctly and/or needs
to be replaced.
NOTE 1: The Portable Wrist Strap Tester may briefly
display “FAIL HIGH” once the test button is released at
the conclusion of a test. Residual voltage in the circuit’s
capacitors causes the test to continue for a split second
after the button is released.
NOTE 2: Failures may be caused by dry skin or minimal
sweat layer. For wrist straps, try using an approved
dissipative hand lotion such as Reztore® ESD
Hand Lotion to your wrist prior to use.
Made in the
United States of America
Packaging
1 Wrist Strap Tester
1 9 V Alkaline Battery
1 Hook and Loop Fastener Strip
1 Certificate of Calibration
DESCO EUROPE - 2A DUNHAMS LANE, LETCHWORTH, HERTFORDSHIRE, SG6 1BE, UK
Phone: +44 (0) 1462 672005 • E-mail: Service@DescoEurope.com, Website: DescoEurope.com
TB-7594 Page 1 of 2
July 2018
© 2018 DESCO INDUSTRIES INC
Employee Owned
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Figure 2. Using the Portable Wrist Strap Tester and
recording its results
Calibration
The Vermason Portable Wrist Strap Tester is calibrated
to NIST traceable standards. There are no user
adjustments necessary. We recommend that calibration
be performed annually using the Charleswater 99090
Calibration Unit. It is a convenient product which allows
the customer to perform NIST traceable calibration on
single-wire personnel testers. The 99090 is designed
to be used at the workstation, virtually eliminating
downtime, verifying that the continuous monitor is
operating within tolerances.
Specifications
Power Supply 9 V Alkaline Battery
Operating Temperature 32 °F to 104 °F (0 to 40 °C)
Test Limits 750 kilohms to 35 megohms
Test Voltage 4 VDC
Dimensions 3.6" x 2.6" x 1.1"
(91 mm x 66 mm x 28 mm)
Weight 4 oz (113 g)
Limited Warranty, Warranty Exclusions, Limit
of Liability and RMA Request Instructions
See the Desco Europe Warranty -
DescoEurope.com/Limited-Warranty.aspx
View technical bulletin PPE-5034.E for more information
on the Charleswater 99090 Calibration Unit and
instructions to calibrate the Portable Wrist Strap Tester.
Figure 3. Charleswater 99090 Calibration Unit
DESCO EUROPE - 2A DUNHAMS LANE, LETCHWORTH, HERTFORDSHIRE, SG6 1BE, UK
Phone: +44 (0) 1462 672005 • E-mail: Service@DescoEurope.com, Website: DescoEurope.com
TB-7594 Page 2 of 2
© 2018 DESCO INDUSTRIES INC
Employee Owned