Desco TB-3040 Installation Manual

TECHNICAL BULLETIN TB-3040

Digital Static Field Meter
Operation and Maintenance

Its accuracy is dependent upon three factors:

• Grounding of the Meter via a ground cord (not

• The instrument must be properly zeroed.

• The distance from the front edge of the case to the

Charged insulators in the ESD protected area can
adversely impact quality, productivity, and reliability.

“When any object becomes electrostatically charged,
there is an electrostatic eld associated with that charge.
If an ESDS (ESD sensitive) device is placed in that
electrostatic eld, a voltage may be induced on the
device. If the device is then momentarily grounded, a
transfer of charge from the device occurs as a CDM
(Charged Device Model) event. If the device is removed
from the region of the electrostatic eld and grounded
again, a second CDM event will occur as charge (of
opposite polarity from the rst event) is transferred from
the device.” (Handbook ESD TR20.20 section 2.7.5
Field Induced Discharges)

Made in America

included) (Meter is also grounded when held by a
grounded operator).

target or surface under examination must be
accurately dened.

Figure 1. Desco 19492 Digital Static Field Meter

Description

The Desco Digital Static Field Meter is a high quality,
portable non-contacting static eld meter which
consistently produces accurate readings with ease and
provides years of trouble-free operation.

The Digital Static Field Meter indicates surface voltage
and polarity on objects up to ±19.99 kV at a distance of
1 inch with an accuracy of ±5% of the displayed value. It
is chopper-stabilized for use under almost any condition
including ionized environments. The conductive case
and ground snap facilitate grounding for accurate
measurement. Also featured are a zero button and a
display hold function. A unique LED rangender
system provides accurate positioning of the Meter from
the target.

Compliance verication should include periodic checks
with a static eld meter to determine if high charging
material is present in the ESD protected area. All
packaging and other materials that may be electrostatic
generative to 2,000 volts must be kept a minimum of 12"
from ESD sensitive items at all times. It is proper to rub
an item and measure that it can charge.

“In order to mitigate eld-induced CDM (Charged Device
Model) damage, the ESD program shall include a plan
for the handling of process-required insulators. If the
eld exceeds 2,000 volts/inch, steps shall be taken to
either:

A. Separate the insulator from the ESD-sensitive device
by a distance of 30 cm (12 inches); or

B. Use ionization or other charge mitigating techniques
to neutralize the charge.” (ANSI/ESDS20.20 section

8.3)

Other steps that can be taken are to remove the item
from the ESD protected area or replace with a static
control protective version of the item.

TB-3040 Page 1 of 6

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DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 • [phone] • Fax [phone]

Rev. June 2009

© 2009 DESCO INDUSTRIES, INC.

Employee Owned

Packaging

1 Digital Static Field Meter
1 9V Alkaline Battery
1 Data Output Cord
1 Certicate of Calibration

C. Analog Output Jack: A low-voltage replica of the
measured voltage is provided at this output. The voltage
at this output is 1/1000th (±2 kV range) or 1/10,000 (±20
kV range) of the measured voltage.

D. POWER Button: Press to turn the unit ON and OFF.

Features and Components

A

B

FRONT VIEW

E. 4mm Stud: Use this stud to ground the Meter using

a 4mm ground cord (not provided - any standard single
wire wrist strap cord can be used).

F. Battery Cover: Slide the cover down to open the 9V
battery compartment.

Operation

Note: The 19492 Digital Static Field Meter is built in a

conductive case. The instrument senses the difference

C

D

in potential between the case (and the person holding
the case / ground connection) and the surface under
test. Ensure that the person using the instrument is
grounded or that the rear panel ground snap connection
is utilized to achieve accurate measurements.

BATTERY CHECK

The battery should be replaced when “BAT” is indicated
on the display. Always replace the battery with a 9V
alkaline or equivalent battery in order to remain CE
compliant.

ZERO THE METER

Turn the meter on by pressing the POWER button.
Press the RANGE / ZERO button to set the meter to
the 2 kV (3 decimal places) range. Point the top of the
Meter approximately 1 inch away from a grounded metal
surface. Use the red LED range guide. The Meter is
properly positioned when the projected red bullseyes
are centered on top of each other. Press and hold the
RANGE / ZERO button until the meter displays “.000”.

E

F

BACK VIEW

Figure 2. Digital Static Field Meter features and
components

A. HOLD Button: Press to freeze the reading on the
display. Press again to return to normal measurement
operation.

B. RANGE / ZERO Button: Press to select the
measurement range. Press and hold to zero the meter.

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TB-3040 Page 2 of 6

MAKING A MEASUREMENT

Place the meter 1 inch from the object to be measured.
This distance is measured from the front edge of the
meter case to the surface of the object. The meter now
displays a reading (from 0 to ±.200 or ±2.00) of the
electrostatic eld in kilovolts per inch.

Note: The red ranging lights are provided to help place
the meter at the correct distance from the object. The
lights are set to produce a concentric red bullseye
pattern on a at opaque surface 1 inch from the front
edge of the meter. This can be practiced by aiming the
meter at a sheet of white paper.

The display will indicate “1” or “-1” when the meter is
over-ranged. Change the range of the unit if necessary.
If the measurement exceeds 20 kV, move the meter
farther away from the object and multiply the reading
by the distance (in inches) away from the object being
measured. The measurement accuracy is dependent on

© 2009 DESCO INDUSTRIES, INC.

Employee Owned

a stable ground reference and the 1 inch measuring
distance. It is also dependent on the “aspect ratio”,
relating the size of the object to be measured to the
measurement distance.

Thousands
Hundreds
Tens

Figure 3. Reading the Digital Static Field Meter while in
the ±20 kV range

Hundreds
Tens
Ones

Note: This aspect ratio should be at least 3 for best

accuracy, i.e. the object should be at least a 3 inch
square when measuring at a 1 inch distance. Accurate
measurements may be made at other measurement
distances by scaling the meter range and observing the
proper aspect ratio. For example, at a measurement
distance of 3 inches, multiply the meter reading by 3 to
give a range of 0 to 60 kilovolts. For accuracy, the object
being measured at this distance should be at least a 9
inch square.

HOLDING THE LAST READING

With the meter positioned 1 inch from the object being
measured, press the HOLD button. This will freeze the
reading from the object on the display and the analog
output signal. This feature allows the operator to move
the meter where it may be more easily read or saved for
later reference.

Note: The red ranging lights will be off while the meter is
in HOLD mode. It is advised to do this between
measurements to prolong battery life.

ANALOG OUTPUT

The analog output jack labeled “OUT” on the face of
the meter accepts a standard 2.5 mm monaural phone
plug and is provided so the output of the Digital Static
Field Meter may be connected to an oscilloscope, strip
chart recorder, external meter or other device. Use the
included cord to achieve a connection between the eld
meter and alternate measuring instrument. The voltage
at this output is 1/1000th (±2 kV range) or 1/10,000 (±20
kV range) of the measured voltage.

BATTERY REPLACEMENT

The Digital Static Field Meter operates from a standard
9 VDC alkaline battery. Battery life is in excess of 50
hours under normal use. When the battery voltage
drops below 6.5 V, “BAT” will appear on the display.
To change the battery, slide the battery cover down at
the back of the Meter and remove the battery from the
battery clip. Replace the battery with a fresh one and re­install the battery cover. The battery should be removed
from the Meter if its is to be stored for an extended
period of time.

Figure 4. Reading the Digital Static Field Meter while in
the ±2 kV range

DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 • [phone] • Fax [phone]

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TB-3040 Page 3 of 6

Maintenance

The Digital Static Field Meter is factory calibrated and no
maintenance is required. If for any reason you believe
the Meter is not working correctly, please contact Desco
Customer Service. CAUTION - There are no user
serviceable parts. Any unauthorized service will void the
warranty and result in additional repair charges.

Note: This Meter is a precision instrument and should
not be subjected to dropping as that would void the
warranty.

© 2009 DESCO INDUSTRIES, INC.

Employee Owned

Specications

Measurement Range (switch selectable)

Low Range: 0 to ±1.99 kV / inch
High Range: 0 to ±19.99 kV / inch

Measurement Accuracy

Voltage Monitor Output: > ±5% of reading ±10 mV
Voltage Display: > ±5% of reading ±2 counts

Measurement Stability

±10 counts

Automatic Shutoff

Unit will shut off after 20 minutes after last switch activity

Power Requirements

One (1) 9V alkaline battery

Operating Time

Greater than 50 hours, with new battery at 21°C
continuous usage

Operating Conditions

Temperature: 10°C to 30°C
Relative Humidity: Up to 80%, non-condensing
Altitude: Up to 2,000 meters

Dimensions

0.94" H x 2.75" W x 4.94" L
(23.9mm H x 69.9mm W x 125.5mm L)

Weight (with battery)

4.9 oz
(140 g)

Voltage Monitor Connection

2.5mm audio jack

CE Certied

Ionization Test Kit Accessories

Desco offers accessories for the Digital Static Field
Meter designed to facilitate routine auditing and periodic
testing of ionization equipment (Ref: ANSI/ESD SP3.3).
The Meter and accessories combination can be used to
test an ionizer’s overall performance. This highly
portable test kit allows the user to make quick and
accurate offset voltage balance level and neutralization
discharge time measurements (counting or using
stopwatch). These accessories are available as Desco
item# 19496 Test Kit Upgrade which includes the
Conductive Plate and Charger.

Figure 5. Installing the 19498 Conductive Plate

18"

12"

Figure 6. Auditing ionization equipment with the Digital
Static Field Meter and Conductive Plate (Ref: ANSI/ ESD
SP3.3)

Desco 19448 Personal HBM Test Fixture

Note: Desco 19498 Conductive Plate required

The Desco 19448 Personal HBM Test Fixture turns your
model 19492 Digital Field Meter into a Human Body
Model tribo-electric charging tester. This kit will allow
you to measure electrical charges generated on the
human body while walking or moving across an
insulative or conductive surface.

TB-3040 Page 4 of 6

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© 2009 DESCO INDUSTRIES, INC.

Employee Owned

It has been specially designed to measure static charges
produced by walking across substrates such as
carpeting, vinyl oor tile, and sealed concrete. It can
also be used to detect charge generation on surfaces
such as conductive or dissipative oor tiles and
carpeting. An ESD technician may also use this tool to
verify proper grounding between a conductive or
dissipative oor 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 ooring
surface, as well as human body capacitance will also
affect the amount of charge
generated.

Installation

A

ground cord

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, shufe 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.

B

Figure 7. Installing the 19448 Personal HBM Test Fixture
on the Digital Static Field Meter with Conductive Plate

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.

DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 • [phone] • Fax [phone]

DESCO EAST - One Colgate Way, Canton, MA 02021-1407 • [phone] • Fax [phone] • Website: Desco.com

Figure 8. Using the Personal HBM Test Fixture to
measure charges on the body

TB-3040 Page 5 of 6

© 2009 DESCO INDUSTRIES, INC.

Employee Owned

Limited Warranty

Desco expressly warrants that for a period of one (1) year from the date of purchase Desco Digital Static Field Meters will be free of defects in
material (parts) and workmanship (labor). Within the warranty period, a credit for purchase of replacement Desco Digital Static Field Meters, or,
at Desco’s option, the Digital Static Field Meter will be repaired or replaced free of charge. If product credit is issued, the amount will be
calculated by multiplying the unused portion of the expected one year life times the original unit purchase price. Call our Customer Service
Department at 909-627-8178 (Chino, CA) or 781-821-8370 (Canton, MA) for a Return Material Authorization (RMA) and proper shipping
instructions and address. Please include a copy of your original packing slip, invoice, or other proof of date of purchase. Any unit under
warranty should be shipped prepaid to the Desco factory. Warranty replacements will take approximately two weeks.

If your unit is out of warranty, call our Customer Service Department at 909-627-8178 (Chino, CA) or 781-821-8370 (Canton, MA) for a Return
Material Authorization (RMA) and proper shipping instructions and address. Desco will quote repair charges necessary to bring your unit up to
factory standards.

Warranty Exclusions

THE FOREGOING EXPRESS WARRANTY IS MADE IN LIEU OF ALL OTHER PRODUCT WARRANTIES, EXPRESSED AND IMPLIED,
INCLUDING MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE WHICH ARE SPECIFICALLY DISCLAIMED.
The express warranty will not apply to defects or damage due to accidents, neglect, misuse, alterations, operator error, or failure to properly
maintain, clean or repair products.

Limit of Liability

In no event will Desco or any seller be responsible or liable for any injury, loss or damage, direct or consequential, arising out of the use of or
the inability to use the product. Before using, users shall determine the suitability of the product for their intended use, and users assume all
risk and liability whatsoever in connection therewith.

TB-3040 Page 6 of 6

DESCO EAST - One Colgate Way, Canton, MA 02021-1407 • [phone] • Fax [phone] • Website: Desco.com

DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 • [phone] • Fax [phone]

© 2009 DESCO INDUSTRIES, INC.

Employee Owned