TB-3040
Page 5 of 6
© 2009 DESCO INDUSTRIES, INC.
Employee Owned
Figure 8. Using the Personal HBM Test Fixture to
measure charges on the body
It has been specially designed to measure static charges
produced by walking across substrates such as
carpeting, vinyl floor tile, and sealed concrete. It can
also be used to detect charge generation on surfaces
such as conductive or dissipative floor tiles and
carpeting. An ESD technician may also use this tool to
verify proper grounding between a conductive or
dissipative floor surface and a person wearing personal
grounding devices such as foot grounders.
The amount (or size) of the charge generated will vary
from one human body to another. Other factors such as
humidity, contamination between the foot and flooring
surface, as well as human body capacitance will also
affect the amount of charge
generated.
Installation
Figure 7. Installing the
19448
Personal HBM Test Fixture
on the Digital Static Field Meter with Conductive Plate
A
B
To obtain the desired result, a ground cord must be
installed onto the 4mm snap on the back of the Field
Meter and attached to a equipment ground or common
ground point.
Operation
In order to obtain the desired test results, the Meter must
be properly grounded as stated in the Installation and
Removal section. Once installed on the Field Meter, the
HBM Test Fixture itself is isolated from the meter case
and ground and should remain that way.
Cradle the Test Fixture in the palm of your hand. Once
the Meter is grounded and you are standing on the
substrate to be tested, simply walk around, shuffle your
feet, raise a foot or use the walking pattern per Figure 1
of ANSI/ESD STM 97.2 to determine if the combination
of footwear and substrate produces an electrical charge.
If an electrical charge is generated and induced onto the
human body, the Test Fixture will transfer that charge
onto the Field Meter, and the amount of the charge will
be registered. If it is necessary to record the amount of
charge, you can save the result by simply pressing the
Hold button on the front of the Field Meter, and
pressing the button with an insulated object. This
test can be done regardless of the type of footwear or
substrate combination. Other items in your ESD Control
Program may also be tested such as conductive or
dissipative chairs. Simply sit in the chair on the desired
substrate and move the chair back and forth to
determine if the chair and human body combination
produces and electrical charge.
A.
Slide the Digital Static Field Meter down into the
Personal HBM Test Fixture.
Note:
The Conductive Plate is required to use the
Personal HBM Test Fixture
B.
Insert the screw from the back of the Personal HBM
Test Fixture.
ground cord
