Desco 95402 Installation Manual

TECHNICAL BULLETIN TB-5500

Combo Wrist Strap / Footwear Tester
Installation, Operation and Maintenance

Pass Range 750K - 10M and 750K - 100M

monitoring should be considered or even required.”

Per ESD SP9.2 APPENDIX B - Foot Grounder Usage Guidance
“Compliance verification should be performed prior to each use
(daily, shift change, etc.). The accumulation of insulative materials
on the FCS may increase the foot grounder system resistance. If
foot grounders are worn outside the ESD protected area testing for
functionality before reentry to the ESD protected area should be
considered.”

Per ESD SP9.2 APPENDIX C -Parallel Ground Paths
“A parallel ground path allows a flow of electrical current through a
path that is not intended for the test. Parallel ground paths may be
caused by several different situations.

For example:

Figure 1. SPI 95402 Combo Tester

Description

The SPI 95402 Combo Tester is a 3-state touch tester designed
for fast, frequent testing of ESD personnel grounding devices.
This product can be used as one of the tools to fulfill the ANSI
ESD S20.20 paragraph 6.1.3.2 “Compliance Verification Plan.
Verification should include routine checks of the Technical
Requirements of the Plan.” The Combo Tester incorporates a
unique dual test circuit design which improves accuracy of testing
and eliminates the need for separate wrist strap and foot grounder
test units. The 95402 is equipped with a 750 kilohm - 10 megohm
circuit, ideal for testing of wrist straps and a 750 kilohm - 100
megohm circuit designed for accurate testing of footwear.

Test parameters are factory set but can be adjusted to match your
own specifications. The 95402 is very simple to operate. A green
light signals the user that everything is OK. A red light and an
audible indicator means that the circuit resistance is either too low
or too high.

The Tester operates on either a 9 volt battery or a special AC
adapter. The Combo Tester is calibrated to NIST traceable
standards and is available in three models.

Model Description

95402 Combo Tester, 9 Volt battery
95403 Combo Tester w/ Footplate
95410 Combo Tester w/ Stand
95407 Foot Plate for Combo Tester
95408 Stand for Combo Tester
95409 AC Adapter, 120V

CAUTION: Use only the AC adapter designed for this unit: Item

95409 (120 volt). Using any other adapters may damage the unit

and void the warranty.

Per ESD Handbook ESD TR20.20 paragraph 5.3.2.4.4 Test
Frequency “Typical test programs recommend that wrist straps
that are used daily should be tested daily. However, if the products
that are being produced are of such value that knowledge of
a continuous, reliable ground is needed, and then continuous

a. The path represented by the person standing with one shoe on

the floor and the other shoe on the test apparatus. A parallel
path may be created by the shoe on the floor. Current from the
test instrument is then directed down two paths when it was
intended to be directed down one. The correct path for the test
is with one shoe in the air or on an insulating surface and the
other shoe on the test plate.

b. The path presented by a person inadvertently supporting

themselves by means of one hand on another object such as
a wall, table or supporting member in order to measure the
resistance in one foot contact. The hand has created a parallel
path to ground.

c. The path represented by a person leaning against another

object with other parts of the body in order to provide physical
support during a testing sequence. This can then lead to other
grounding paths and erroneous results.”

Packaging

Remove the Tester from the carton and inspect for damage.

Items included with model 95402:

1 Combo Tester
1 9 volt battery

Items included only with model 95403:

1 Combo Tester
1 Foot plate
1 Ground cord
1 9 volt battery

Items included only with model 95410:

1 Combo Tester
1 Base plate
1 Pedestal tube with bracket and boot installed
1 4” banana plug connector
1 Vinyl insulator cap
1 Wall poster
1 5/32” hex wrench
1 9 volt battery

Model numbers 95403 and 95410 are ideally suited for testing foot
grounding devices.

Made in America

ESD Systems.com • 432 Northboro Road Central • Marlboro, MA 01752 • [phone] • Fax [phone] • Website: ESDSystems.com

TB-5500 October 2009 Page 1 of 4

© 2008 DESCO INDUSTRIES INC.

Employee Owned

Installation

The Combo Tester may be used as a portable unit, or may be
permanently mounted on either a table or a wall. Please refer to
the following instructions when installing your tester.

Stationary Installation

If you will be using the tester as a portable unit, you may prefer
to mount the unit to a table or wall. Three keyhole slots on the
back of the unit are included to allow you to attach the tester to a
stationary surface.

Figure 2. Mounting hole locations

I. Select location for mounting Tester. Install three #6 or #8
screws spaced as illustrated in figure 3, into a wall or other
vertical surface. Make sure that the screw heads do not project
out more than 1/4” from mounting surface. The template on
page four is actual size.

II. Mount the Tester on the screws, pulling down to lock it in place.

Figure 4. Replacing the battery

General Instructions

In the following test configurations, the 95402 can be used to
test wrist straps while they are worn. Models 95403 and 95410

will also allow the user to test footwear. Insertion of the banana
plug on the wrist strap cord activates the wrist strap tester circuit
and deactivates the footwear test circuit. NOTE: When testing or
calibrating, press and hold for test results, then allow 1-2 seconds
for the unit to reset before pressing the test button again.

WRIST STRAP TESTING WITH MODEL 95402

This test safely checks that a continuous path between the
operator, wrist strap and ground cord exists.

I. While wearing the wrist strap, plug the banana plug end of the
cord into the jack on the face of the unit.

II. Press rocker switch toward “WRIST CORD”.

III. Press the test button so that the unit activates. Hold down for
2-3 seconds.

NOTE: DO NOT TOUCH ANY OTHER METAL WHILE
PERFORMING TEST.

Figure 3. Stationary installation of the Combo Tester

Operation

The Combo Tester can be operated either on battery or AC power.
The unit comes equipped with a 9 volt alkaline battery. For AC
operation, plug the optional AC adapter into the mini phone jack
located on the upper left hand corner of the tester. The AC

adapter is sold separately as item 95409 (120 volt).

LOW BATTERY INDICATOR

The Combo Tester includes a low battery indicator alarm circuit.
If both the audible alarm and indicator LED turn on during use,
discontinue testing and replace the battery. The tester will
continue to operate with a weak battery, but results should not be
considered accurate.
The battery can be easily replaced by removing the battery
compartment cover on the back of the unit and installing a new 9
volt battery.

ESD Systems.com • 432 Northboro Road Central • Marlboro, MA 01752 • [phone] • Fax [phone] • Website: ESDSystems.com

TB-5500 Page 2 of 4

Figure 5. Testing the wrist strap

IV. Lighting of the green “PASS” LED indicates that the wrist strap
and ground cord assemblies are functioning properly.

V. If either “FAIL LO” or “FAIL HI” LEDs light and the audible
indicator sounds, the wrist strap wearer should check the wrist
strap assembly immediately.

TESTING FOOT GROUNDING DEVICES

In order to test footwear you will need the model 95403 or 95410
Combo Tester. The following instructions are intended for use
while wearing foot grounding devices. When using a Footwear
Tester that does not use a split footplate, one needs to test one
foot at a time; best practice is to raise the other foot off the floor.
When testing conductive shoes, or foot grounders worn on both
feet, test each foot separately to test the separate path-to-ground.
If the floor is an ESD floor, placing the other foot on the floor may
result in erroneous test results. Care should also be taken not to
create (hand resting on wall or bench) other paths-to-ground.

© 2008 DESCO INDUSTRIES INC.

Employee Owned