TB-2004 March 2011 Page 1 of 3
Figure 1. Model
Figure 2.
The wrist strap being tested may be plugged directly to the tester
or any convenient common ground point. The wrist strap will test
properly as long as both the Touch Tester and the wrist strap are
connected to a common ground. Therefore, any number of wrist strap
wearers may use the Touch Tester if they can conveniently reach
it. Desco item
straps.
When the Touch Tester and a
(utility ground) wrist straps plugged into the
Description
Per ANSI/ESD S20.20, test equipment is required to enact
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 program
plan.
The Touch Tester is an “on demand” wrist strap tester that also
functions as a common-point ground for two wrist straps and a mat.
When the wearer of a wrist strap touches the metallic surface of the
Touch Tester, a path for current flow is completed from the wearer’s
skin, through the wrist strap, to the metallic surface to ground. This
action will cause the green “test good” LED to light (and the optional
audible signal to sound) as long as the resistance of the circuit path
is between 750k ohms and 10 megohms.
Touch Tester - Operation,Installation
and Calibration Instructions
Pass Range 750K Ohms to 10 Megohm 120VAC Operation
GROUND (09740)
WRIST STRAP
19350
09740
19350
Testing Circuit
DESCO EAST -
provides two banana jacks for grounding wrist
Wrist Strap Tester / Common Point Ground
09740
DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 • (909) 627-8178 • Fax (909) 627-7449
One Colgate Way, Canton, MA 02021-1407 • (781) 821-8370 • Fax (781) 575-0172 • Web Site: Desco.com
TECHNICAL BULLETIN TB-2004
are tied to a common ground
09740
19350
can also be tested.
Figure 3. Testing a wrist strap
Figure 4. Installation of Touch Tester
Installation
The Touch Tester is easily attached at the workstation. A snap stud
at ground reference is provided on the back of the unit, allowing it to
be snapped directly to a mat. In this configuration, the unit provides
a common-point ground for both the mat and the wrist strap, and is
easily accessible for frequent testing. A piece of adhesive backed
hook and loop fastener is provided for the user as an alternative
mounting method preventing the tester from rotating.
The hook-and-loop type fastener also allows fast mounting to smooth
surfaces. This method is convenient for mounting the tester on a
workstation leg or on an upright support for shelving or lights. (Note -
the snap does not have to be connected for proper grounding).
Equipment Rating:
AC Adapter rated 120 Vac, 60 Hz, 6 W.
Ground Touch Tester rated 6.5 Vdc, 50 mA.
Environmental Conditions
• Suitable for indoor use only at altitudes not exceeding 6500 ft.
• Temperature range of 41°F (5°C) to 104°F (40°C)
• Maximum relative humidity of 80% up to 88°F (31°C) decreasing
• Pollution degree 2 per IEC 664
• Installation Category II
CAUTION: If this equipment is used in a manner not specified by
the manufacturer, the protection provide by the equipment may be
impaired.
(2Km)
linearly to 50% @ 104°F (40°C)
© 2011 DESCO INDUSTRIES INC.
Made in America
Employee Owned
