TB-3066
Page 1 of 8
© 2017 DESCO INDUSTRIES, INC.
Employee Owned
DESCO WEST
- 3651 Walnut Avenue, Chino, CA 91710 • (909) 627-8178
DESCO EAST
- One Colgate Way, Canton, MA 02021-1407 • (781) 821-8370 • Website:
Desco.com
Combo Tester X3
Installation, Operation and Maintenance
Description
The Desco Combo Tester X3 verifies the functionality
of an operator’s wrist strap and footwear. It determines
if an operator’s wrist strap and footwear will function
correctly. The operator’s wrist strap and footwear will
test simultaneously with no need for separate tests.
Green lights indicate that the wrist strap and footwear
are passing. Red lights and an audible alarm indicate
when the wrist strap and/or footwear (left or right) are
failing. If failure occurs, the tester will also display if the
grounding device’s resistance is too low or too high.
The Combo Tester X3 features a reliable and durable
solid-state switch which replaces the traditional
mechanical test switch with a spring and moving parts.
The outer and inner portions of the solid-state switch are
designed to be bridged by a person’s skin. The Combo
Tester X3 is compatible with both single-wire and
dual-wire wrist straps.
The factory test limits are set to:
Wrist Straps: 750 kilohms and 10 megohms
Footwear:
750 kilohms and 35 megohms
(See page 3 for alternate test limit settings)
Each Combo Tester X3 is calibrated with accepted
procedures and standards traceable to the National
Institute of Standards and Technology (NIST) and
includes a NIST certificate.
December 2017
The Combo Tester X3 and its accessories are available
as the following item numbers:
Item
Description
19278
Combo Tester X3
19279
Combo Tester X3 with Stand
19255
Stand, for Combo Tester X3
50755
ESD Glove Test Fixture
50424
Limit Comparator
19262
Power Adapter, 100-240VAC Input, 12VDC
0.5A Output, All Plugs
50406
Replacement Dual Foot Plate
Per ANSI/ESD S20.20 section 7.3 “A Compliance
Verification Plan shall be established to ensure the
Organization’s fulfillment of the technical requirements
of the ESD Control Program Plan. Process monitoring
(measurements) shall be conducted in accordance
with a Compliance Verification Plan that identifies the
technical requirements to be verified, the measurement
limits and the frequency at which those verifications
shall occur. The Compliance Verification Plan shall
document the test methods and equipment used for
process monitoring and measurements. … The test
equipment selected shall be capable of making the
measurements defined in the Compliance Verification
Plan.”
Per ANSI/ESD S1.1 Annex A.3 Frequency of System
Testing “The wrist strap system should be tested daily to
ensure proper electrical resistance.”
Per ESD Handbook ESD TR20.20 section 5.3.2.4.2
Additional User Wrist Strap Testing “Proper testing of
the wrist strap includes the resistance of the groundable
point on the end of the cord, the cord itself, the resistor,
the cord-to-cuff snap connector, the resistance of the
interface of the cuff, the cuff/wrist interface, and the
resistance of the person between the wrist and the hand
that contacts the test electrode.”
Per ESD Handbook ESD TR20.20 section 5.3.2.2.2
Wrist Strap Ground Cord “At first glance, the ground
cord appears to be a relatively simple assembly.
However, the design requirements are considerable,
given the wide range of user applications and the
durability requirements of constant tugging, flexing,
and dragging over the edge of workstation tops and
equipment chassis.”
Made in the
United States of America
Figure 1. Desco Combo Tester X3 and Dual Foot Plate
TECHNICAL BULLETIN TB-3073
