ETS 230 User manual

NANOCOULOMBMETER
Model 230
Operating Manual
8/17

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1.0 INTRODUCTION
The evaluation of triboelectric charge generation is performed either by measuring the
voltage build up on material after it has been separated from the same or different
material or by measuring the amount of charge developed on the material. When used
with a suitable Faraday cup, the charge on a wide range of material types and sizes can
accurately be measured by the Model 230 Nanocoulombmeter.
The Model 230 is a complete instrument for measuring charge directly in
nanocoulombs. The instrument is available with either a 3.125” (79mm) diameter
Faraday cup, a 12” (305mm) diameter Faraday pail, a 24”x24”x22” (610x610x559mm)
Faraday Bucket; a detector probe or it can be used alone to measure the charge on
capacitors or from capacitive discharge systems (with adequate protection).
The Nanocoulombmeter has 3 user selectable ranges of 20, 200 and 2000
nanocoulombs to cover a wide range of charge measurement applications. The
resolution of the 20 nC scale is 0.01 nC. Drift is <0.05 nC/minute. The instrument
incorporates a built in precision 1.0 Volt output along with a precision 0.10 µF, 1%
capacitor for checking system calibration.
The Model 230 meets the requirements for charge measurement as specified in
applicable ESDA, ASTM, EIA, DOD as well as many other industry standards.
2.0 EQUIPMENT DESCRIPTION
The Model 230, shown in Figure 1.0-1, is powered by two 9-Volt alkaline batteries that
are readily accessible from the rear of the instrument. An optional AC Power module is
available to operate the unit from 95-240VAC, 50/60Hz. A “Low Battery” function warns
of low battery voltage (<12.2 Volts). The instrument is housed in a 7.5"L x 10"D x 3"H
(190x245x70mm) aluminum case that provides extra shielding from external fields.
Figure 2.0-1: Model 230 Nanocoulombmeter front panel
The front panel consists of a 2 line / 16 character LCD digital readout with 0.171 inch
numerals, a 3 push-buttons for RANGE selection, a READ/ZERO push-button, a 1.0
Volt CAL output, POWER ON/OFF switch, and a standard BNC input signal connector.
Each depress of a push-button will either select a range (20nC, 200nC, 2000nC) or flip
it (between READ/ZERO).

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The rear panel, shown in Figure 2.0-2, consists of the battery compartment, a ground
(GND) terminal for referencing the instrument to ground as well as grounding the
reference capacitor, a remote READ/ZERO output jack, and a Recorder Output BNC
connector.
Figure 2.0-2: Model 230 Nanocoulombmeter rear panel
The remote READ/ZERO jack enables a remote push-button to be used to place the
instrument in the READ mode. When the optional remote push-button is plugged into
this jack it parallels the READ/ZERO push-button on the front panel, allowing either
button to control this function. This feature makes operating the Model 230 very easy
while making measurements in locations such as humidity controlled glove boxes.
A 0-1.99 Volt signal is available at the Recorder Output corresponding to a 0-full scale
reading of the RANGE selected.
Three different standard size Faraday cups/buckets shown in Figures 2.0-3a, b &c are
available. Special Faraday cups or buckets can also be provided on special order. The
Model 231, 3.125" (79mm) and the Model 232, 12" (305mm) units consist of two round
concentric aluminum containers assembled together with Teflon insulators between
them. The outer can is connected to ground and the inner can comprises the sensing
input. A cover is supplied to completely shield the inner can when making critical
measurements in a high electrostatic field environment.
a
. Model 231 b. Model 232 c. Model 233
Figure 2.0-3: Standard Faraday cups/buckets
The large 24"x24"x22" (610x610x589mm) Faraday Bucket (Model 233) is a welded
assembly that is fabricated from 0.093" aluminum. This bucket is designed for

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evaluating large material samples or complete assemblies. All Faraday cups and
buckets are connected to the instrument by a 3-foot Tefloninsulated cable.
The Model 234 Charge Detector Probe shown in Figure 2.0-4 is designed to measure
charge on the surface of an object while it is being triboelectrically charged due to motion
of another media flowing, rubbing or separating from the test object.
Figure 1-1: Model 234 Charge Detector Probe
3.0 OPERATION
Connect the Faraday cup or bucket to the BNC INPUT connector located on the front
panel of the instrument as shown in Figure 3.0-1. If the remote READ/ZERO push-
button and or a recording device are being used, connect them to the respective output
connectors located on the rear panel.
Figure 3.0-1: Faraday cup connections
Signal output
Remote
ZERO/READ cable
Plug-in
Conical Tip

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3.1 Preliminary Checkout
Push the POWER button to turn it on. At power on, unit defaults to ZERO
STANDBY mode and RANGE is set to 200nC.
Connect the 0.10 µF test capacitor supplied with the instrument to the ground
jack located on the rear panel and touch the other terminal to the 1.0 Volt output
jack located on the front panel. Push READ/ZERO button or depress and
release the remote foot switch to switch to READ mode and touch the charged
capacitor to the inner can of the Faraday cup. The DPM should indicate
100±2nC.
Place the cover on the Faraday cup or bucket. With the RANGE switch set to the
20 nC position, place the READ/ZERO switch in the READ position and observe
the DPM for one minute. The reading should not exceed 0.05nC. Return the
switch setting to the ZERO STANDBY. This provides an initial checkout of the
system performance.
To make a measurement, first select the RANGE desired (20, 200 or 2000nC).
Then place the READ/ZERO switch in the READ position or activate the remote
READ/ZERO switch immediately prior to placing the charged object to be
measured into the cup or bucket. Allow approximately 2 seconds before taking a
reading. If the reading is very low (measurable in the next lower range) or is over
scale, change the RANGE switch setting and repeat the measurement.
Each time a new measurement is taken the READ/ZERO button must first be
placed in the ZERO STANDBY. When using the ETS Foot Operated Remote
READ/ZERO switch the system is functioning as normal. When the foot switch is
depressed and released the system flips between the READ/ZERO mode and
remains in that mode until the switch is depressed again to switch mode.
When making a measurement it is extremely important that the operator
minimize the generation of any electrostatic fields. These fields can be
detected and they will adversely affect the measurement. Cable movement also
may cause a triboelectric charge to be generated on the inner conductor of the
shielded input cable and thus any cable movement should be avoided. If the
measurement cannot be performed without generating extraneous electrostatic
fields, the cover should be placed over the Faraday cup immediately after the
charged object has been placed inside, and then the reading taken.
The instrument can also be used to precisely determine the total capacitance of
an electronic network by charging the network with a given precise voltage and
then discharging the network into the Nanocoulombmeter. If voltages over 10
Volts are used then a 1 MegOhm resistor must be placed in series with the input.
Taking measurements using the Model 234 Detector Probe is covered in its
respective Instruction Manual.
Otherwise, damage to the instrument may occur. The maximum voltage allowed
for this type of measurement SHOULD NOT EXCEED 1000 Volts. Using the

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relationship Q=CV, the desired capacitance of the network (C) may be calculated
by dividing the indicated charge (Q) by the known charging voltage (V).
For example, in a number of specifications such as Mil-Std-263A and EIA-541
the capacitance of an ESD simulator discharge network is specified at a voltage
of 1000 Volts. To determine the capacitance, connect a 1 MegOhm resistor in
series with the simulator output and the Model 230 input. Set the charging
voltage to precisely 1000 Volts, then discharge the capacitor into the
Nanocoulombmeter. A reading of 100nC on the DPM will correspond to a
capacitance of 100pF using the formula:
C = Q/V
= 100x10-9/1x103
= 100pF
4.0 CALIBRATION
The Model 230 is calibrated at the factory using instrumentation traceable to N.I.S.T.
Periodic recalibration of any measuring instrument is required if measurement
accuracies and proper system performance are to be assured. In most applications,
recalibration should be performed on a yearly basis. Contact ETS for recalibration
service.
The user can check the calibration of the instrument at any time by using the supplied
0.10µf, 1% polystyrene capacitor, and a calibrated voltmeter having an input impedance
greater than 1 MegOhm to verify the accuracy of the built-in voltage source. The
capacitor, when charged to 1.00 Volt will produce a reading on the DPM of 100±2nC.
This procedure provides a system check and is not a substitute for periodic laboratory
calibration.
To check the calibration of the measurement set-up, connect the clip lead of the
calibration check capacitor to the ground terminal on the rear panel or to the outer shell
of the Faraday cup or bucket. Select the 200nC RANGE. Touch the lead from the
capacitor to the CAL output connector on the front panel. Push the READ/ZERO button
to switch to READ mode and then touch the capacitor lead to the inner can or directly to
the BNC input connector if a Faraday cup or bucket is not being used. The DPM should
read 100±2 nC
The other ranges can also be checked with the same capacitor if a precision voltage
source is available. 0.10 Volts applied to the capacitor will produce a reading of 10nC in
the 20nC RANGE and 10.0 Volts applied to the capacitor will produce a reading of
1000nC in the 2000nC RANGE.
Additional points can also be checked by using different voltages and/or capacitor
values (must be known to within 1% and be of the low leakage type). Using the
relationship Q(nC)=C(µF) V(Volts) any calibration value can be obtained.
5.0 MAINTENANCE

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The Model 230 Nanocoulombmeter is designed with low current circuits that provide
approximately 20 hours of continuous use from a pair of 9-Volt Alkaline (Duracell Type
MN 1604 or equivalent) batteries. When the “Low Battery” shows 12.2 Volts, the
batteries should be replaced to retain measurement accuracy.
To change batteries, remove the battery cover mounted on the rear panel. The
batteries are connected to the instrument by a pair of standard 9-Volt battery clips. Both
batteries should be replaced at the same time. Replace the battery cover.
If the instrument fails to operate properly it should be returned to ETS for repair and
recalibration. A Return Material Authorization (RMA) must be obtained from ETS prior
to sending in the instrument. The instrument should be packed in adequate packaging
to avoid incurring any shipping damage.
6.0 SPECIFICATIONS
READOUT: 2 line / 16 character LCD digital meter
RANGE: 20, 200, 2000 nC full scale
RESOLUTION:
20 nC RANGE: 0.01 nC
200 nC RANGE: 0.1 nC
2000 nC RANGE: 1.0 nC
DRIFT: <0.05 nC/minute
ACCURACY: 2.0% full scale (max), ±1 digit
ZEROING: Fully Auto, Front Panel READ/ZERO button & Remote button input
RECORDER OUTPUT: 0 - ±1.99 Volts, Source Impedance: 1 Ohm (max), BNC
connect
CALIBRATION OUTPUT: +1.00 Volts, ±1%
CALIBRATION CAPACITOR: 0.100 µF, ±1%
BATTERY: 2 each, 9 Volt Alkaline (Duracell MN1804 or equiv.)
Battery Life: 20 hours (min) continuous use, 6-12 months (est.) under normal use
AC Power Module (+ center): 90-260VAC, 50/60Hz (Optional)
OPERATING ENVIRONMENT: 20±10º C, 0-60% R.H. (non-condensing)
DIMENSIONS: 7.5"L x 10"D x 3"H (190x245x70mm)
WEIGHT: 3.3 lbs. (1.5kg)
FARADAY CONTAINERS:
Model 231 Cup: 3.125" (79mm) Diameter
Model 232 Pail: 12.0" (305mm) Diameter
Model 233 Bucket: 24"x24 x22" (610x610x559mm)
Model 234 Probe:
ACCESSORIES: PART#230-5844: Foot operated READ/ZERO switch
PART#230-5845: 90-260VAC, 50/60Hz (Optional)
PART#230-5847: 0.01 & 1.0 µF Test Capacitors
PART#705-5848: Foot Operated Accessory ON/OFF Switch for
ionizer
7.0 WARRANTY
Electro-Tech Systems, Inc. warrants its equipment, accessories and parts of its

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manufacture to be and remain free from defects in material and workmanship for a
period of one (1) year from date of invoice. It will, at the discretion of Seller, either
replace or repair without charge, F.O.B. Glenside, similar equipment or a similar part to
replace any equipment or part of its manufacture which, within the above stated time, is
proved to have been defective at the time it was sold. All equipment claimed defective
must be returned properly identified to the Seller (or presented to one of its agents for
inspection). This warranty only applies to equipment operated in accordance with
Seller's operating instructions.
Seller's warranty with respect to those parts of the equipment that is purchased from
other manufacturers shall be subject only to that manufacturer's warranty.
The Seller's liability hereunder is expressly limited to repairing or replacing any parts of
the equipment manufactured by the manufacturer and found to have been defective.
The Seller shall not be liable for damage resulting or claimed to result from any cause
whatsoever.
This warranty becomes null and void should the equipment, or any part thereof, be
abused or modified by the customer of if used in any application other than that for
which it was intended. This warranty to replace or repair is the only warranty, either
expressed or implied or provided by law, and is in lieu of all other warranties. The Seller
denies any other promise, guarantee, or warranty with respect to the equipment or
accessories. In particular, as to its or their suitability for the purposes of the buyer or its
or their performance, either quantitatively or qualitatively or as to the products which it
may produce and the buyer is expected to expressly waive rights to any warranty other
than that stated herein.
ETS must be notified before any equipment is returned for repair. ETS will issue an
RMA (Return Material Authorization) number for return of equipment.
Equipment should be shipped prepaid and insured in the original packaging. If the
original packaging is not available, the equipment must be packed in a sufficiently large
box (or boxes if applicable) of double wall construction with substantial packing around
all sides. The RMA number, description of the problem along with the contact name and
telephone number must be included in formal paperwork and enclosed with the
instrument. Round trip freight and related charges are the owner’s responsibility.