IET Labs 1409 Series User manual

¨PRECISION INSTRUMENTS FOR TEST AND MEASUREMENT ¨
Email: inf[email protected]
TEL: [phone] • FAX: [phone]
www.ietlabs.com
IET LABS, INC.
1409 Series
Capacitance Standard
Operation Manual
Copyright © 2022 IET Labs, Inc.
Visit www.ietlabs.com for manual revision updates
1409 im/May 2022

¨PRECISION INSTRUMENTS FOR TEST AND MEASUREMENT ¨
Email: inf[email protected]
TEL: [phone] • FAX: [phone]
www.ietlabs.com
IET LABS, INC.

i
WARRANTY
We warrant that this product is free from defects in material and workmanship and, when properly used,
will perform in accordance with applicable IET specifications. If within one year after original shipment,
it is found not to meet this standard, it will be repaired or, at the option of IET, replaced at no charge when
returned to IET. Changes in this product not approved by IET or application of voltages or currents greater
than those allowed by the specifications shall void this warranty. IET shall not be liable for any indirect,
special, or consequential damages, even if notice has been given to the possibility of such damages.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED,
INCLUDING BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTABILITY OR
FITNESS FOR ANY PARTICULAR PURPOSE.

ii
1409 Series
Safety Symbols
General definitions of safety symbols used on the instrument or in manuals are listed below.
Caution symbol: the product is marked with this symbol when it is necessary for the user to
refer to the instruction manual.
Hazardous voltage symbol: the product is marked with this symbol when high voltage maybe
present on the product and an electrical shock hazard can exist.
Indicates the grounding protect terminal, which is used to prevent electric shock from the
leakage on chassis. The ground terminal must connect to earth before using the product
Direct current.
Alternating current.
Frame or chassis terminal. A connection to the frame (chassis) of the equipment which
normally includes all exposed metal structures.
On supply.
Off supply.
Hot surface. Avoid contact. Surfaces are hot and may cause personal injury if touched.
Disposal
Waste Electrical and Electronic Equipment (WEEE) Directive 2002/96/EC
This product complies with the WEEE Directive (2002/96/EC) marking requirements.
The affixed label indicates that you must not discard this electrical/ electronic product in domestic
household waste.
Product Category: With reference to the equipment types in the WEEE directive Annex 1, this product
is classified as a “Monitoring and Control instrumentation” product.
Do not dispose of electrical appliances as unsorted municipal waste, use separate collection facilities.
Contact your local government for information regarding the collection systems available. If electrical
appliances are disposed of in landfills or dumps, hazardous substances can leak into the groundwater
and get into the food chain, damaging your health and well-being.
When replacing old appliances with new one, the retailer is legally obligated to take back your old ap-
pliances for disposal.
Proposition 65 Warning for California Residents
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov.
This product may contain chemicals known to the State of California to cause cancer, birth defects, or
other reproductive harm

iii
1409 Series
SAFETY PRECAUTIONS
The following general safety precautions must be observed during all phases of operation, service, and repair of
this instrument. Failure to comply with these precautions or with specific WARNINGS elsewhere in this manual
may impair the protection provided by the equipment. Such noncompliance would also violate safety standards
of design, manufacture, and intended use of the instrument.
IET Labs assumes no liability for the customer’s failure to comply with these precautions.
If an instrument is marked CAT I (IEC Measurement Category I), or it is not marked with a measurement category,
its measurement terminals must not be connected to line-voltage mains.
The 1409 is an indoor use product.
DANGEROUS PROCEDURE WARNINGS
Comply with all WARNINGS - Procedures throughout in this manual and instructions on the instrument prevent
you from potential hazard. These instructions contained in the warnings must be followed.
CAUTION
• DO NOT Operate in an Explosive Atmosphere
• Do not operate the instrument in the presence of inflammable gasses or fumes
• Operation of any electrical instrument in such an environment clearly constitutes a safety hazard
• Use Caution around live circuits and whenever hazardous voltages > 45 V are present
• Operators must not remove instrument covers
• Component replacement and internal adjustments must be made by qualified maintenance personnel only
• DO NOT substitute parts or modify the instrument
• When working with high voltages; post warning signs, train personnel and keep unauthorized personnel away.
Do not apply any voltage or currents to the terminals of the instrument in excess of the maximum limits
indicated in the specifications section of this manual.
To avoid the danger of introducing additional hazards, do not install substitute parts or perform unauthorized
modifications to the instrument.
Return the instrument to an IET Labs for service and repair to ensure that safety features are maintained in
operational condition.

iv
WARNING
OBSERVE ALL SAFETY RULES
WHEN WORKING WITH HIGH VOLTAGES OR LINE VOLTAGES.
Dangerous voltages may be present inside this instrument. Do not open the case
Refer servicing to qualified personnel
HIGH VOLTAGES MAY BE PRESENT AT THE TERMINALS OF THIS INSTRUMENT
WHENEVER HAZARDOUS VOLTAGES (> 45 V) ARE USED, TAKE ALL MEASURES TO
AVOID ACCIDENTAL CONTACT WITH ANY LIVE COMPONENTS.
USE MAXIMUM INSULATION AND MINIMIZE THE USE OF BARE
CONDUCTORS WHEN USING THIS INSTRUMENT.
Use extreme caution when working with bare conductors or bus bars.
WHEN WORKING WITH HIGH VOLTAGES, POST WARNING SIGNS AND
KEEP UNREQUIRED PERSONNEL SAFELY AWAY.
CAUTION
DO NOT APPLY ANY VOLTAGES OR CURRENTS TO THE TERMINALS OF THIS
INSTRUMENT IN EXCESS OF THE MAXIMUM LIMITS INDICATED ON
THE FRONT PANEL OR THE OPERATING GUIDE LABEL.

Contents
Chapter 1 Introduction ..............................................................................1
1.1 Introduction........................................................................................................... 1
Chapter 2 Specifications ...........................................................................2
Speci!cations ................................................................................................................ 2
Chapter 3 Operation ..................................................................................4
3.1 Initial Inspection and Setup .................................................................................. 4
3.2 Connections to Capacitor...................................................................................... 4
3.3 Environmental Conditions .................................................................................... 4
3.3.1 Operating Temperature ............................................................................... 4
3.3.2 Storage Temperature ................................................................................... 5
3.4 Shipping and Handling ......................................................................................... 5
Chapter 4 Maintenance..............................................................................7
4.1 Preventive Maintenance........................................................................................ 7
4.2 Calibration............................................................................................................. 7
4.2.1 Calibration Interval..................................................................................... 7
4.2.2 General Considerations............................................................................... 7
4.2.3 Calibration Procedure ................................................................................. 8
4.3 Replaceable Parts .................................................................................................. 8
v

vi

1
1409 Series
1Introduction
Chapter 1
INTRODUCTION
1.1 Introduction
The 1409 Standard Capacitors (Figure 1-1) consist of
highly stable mica capacitors. They are used as two or
three-terminal reference or standards in a laboratory.
Typical capacitors, observed over decades, have
shown a stability of <±0.01% in measured capacitance
with no systematic drift.
The capacitors are made out of silvered-mica and foil,
spring-held in a heavy metal camp for mechanical
stability. The units are heat-cycled for stability, placed
in a cast aluminum case with silica gel for continuous
desiccation, and sealed with high-temperature potting
compound.
A well is provided in the wall of the case for insert-
ing a dial-type thermometer. For convenient parallel
connection without error, three jack-top binding posts
are provided on the top case, with removable plugs
on the bottom.
Figure 1-1: 1409 Series Capacitance
Standards

2
1409 Series
2 Specifications
Chapter 2
SPECIFICATIONS
For convenience to the user, the pertinent speci•cations are given in a label, shown in Figure 2-3 a•xed to the
case of the instrument.
Calibration and Test Conditions:
Calibrated at 23°C, <50% RH, Traceable to SI
1 nF - 1 µF: Units are calibrated as both 2-terminal and as
3-terminal capacitors. For 2-terminal measurements, the LO
terminal is shorted to the GND terminal. The Adjustments
to Nominal speci•ed in the table above apply to 2-terminal
measurements.
10 µF - 1000 µF: Units are calibrated as 5-terminal
capacitors, "series model"
Series Inductance:
for 0.01 µF - 1 µF: typically < 0.06 µH
Series Resistance:
for 0.01 µF - 0.1µF: 0.02 Ω
for 1 µF: 0.03 Ω
Nominal
value Model
Initial
Adjustment
to nominal*
Temperature
coefficient
(ppm/°C)
Calibration
frequency
Dissipation
(typical)
Stability
(per year)
Max voltage
Terminals Capacitor type
Peak (V) Max
Frequency
1 nF 1409-F ±0.02% 20 1 kHz 0.0003 ±100 ppm 500 10 kHz
2 bp's + gnd
Silvered Mica
mechanically stabilized
hermetically sealed
10 nF 1409-L ±0.02% 20 1 kHz 0.0003 ±100 ppm 500 10 kHz
100 nF 1409-T ±0.02% 20 1 kHz 0.0003 ±100 ppm 500 10 kHz
1 µF 1409-Y ±0.02% 20 1 kHz 0.0002 ±100 ppm 500 10 kHz
10 µF 1409-10µF ±0.04% ±50 100 Hz 0.0005 ±200 ppm 22 Vrms† 1 kHz
4 bp's + gnd
Metallized Polypropyl-
ene Sulfide (MPPS)
hermetically sealed
100 µF 1409-100µF ±0.05% ±50 100 Hz 0.001 ±500 ppm 22 Vrms† 1 kHz
1,000 µF 1409-1000µF ±0.4% -150 100 Hz 0.001 ±500 ppm 22 Vrms† 1 kHz
Custom 1409-X customer-selected value and power specifications
† Maximum allowable Vrms; subject to maximum Vdc = 50 V and max Vrms = (39000/f) for C = 10 µF;
(26000/f) for C = 19 µF; (13000/f) for C ≤100µF, where f = frequency (in Hz).
* Initial Adjustment to nominal is only applicable when manufactured
Frequency Characteristics:
Varies as √f above 100 kHz. See figure 1.
Leakage Resistance:
5,000 ohm-Farads or 100 GΩ, whichever is less
Environment:
Operating: +10 to +40°C, <80% RH
Storage: -20 to +65°C
Specifications
1409 Mechanical Information:
Values Dimensions Weight
1 nF - 100 nF
10.2 cm H x 8.3 cm W x 5.1 cm D
(4.0" x 3.3" x 2.0") 0.6 kg (1.25 lb)
1 µF
14.3 cm H x 8.3 cm W x 6.9 cm D
(5.6" x 3.2" x 2.7") 1.1 kg (2.25 lb)
10 µF - 100 µF
8.6 cm H x 10.5 cm W x 12.7 cm D
(3.4" x 4.15" x 5.0") 0.73 kg (1.6 lb)
1,000 µF
31 cm W x 8.9 cm H x 10.2 cm D
(12.2" x 3.5" x 4") 1.7 kg (3.8 lb)

3
1409 Series
3Specifications
Frequency characteristics:
Figure 2-1: Change in capacitance as a function of
frequency
Dissipation characteristics
See •gure 2-2 and table above.
Figure 2-2: Dissipation factor as a function of
frequency
Figure 2-3: Sample label attached to a 1409 unit
Capacitor Type: Silvered mica and foil pile, spring-held in a
heavy metal clamping structure for mechanical stability.
Calibration: Measured value is capacitance added when
standard is plugged directly into binding posts.
Stability: <0.01% per year.
Temperature Coefficient of Capacitance: +20 ppm/oC,
between 10oand 50oC.
Leakage Resistance: 5000 ohm-farads or 100 GΩ.
SCA CAPACITANCESTANDARD
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GenRad
Westbury, NY 11590
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4
1409 Series
4 Operation
Chapter 3
OPERATION
3.1 Initial Inspection and Setup
This instrument was carefully inspected before ship-
ment. It should be in proper electrical and mechanical
order upon receipt.
To provide ready reference to speci•cations, a label,
shown in Figure 2-3, is attached to the case of the
instrument.
3.2 Connections to Capacitor
1 nF - 1 µF 1409 capacitors have 3 binding posts --
HI, LO, and GND -- as shown in •gure 3-1.
10 µF - 1000 µF 1409 capacitors have 5 binding
posts -- Sense HI, Current HI, Sense LO,
Current LO and GND -- as shown in •gure 3-2
and 3-3.
Figure 3-1: 1409 capacitor standards
Figure 3-2: 10 and 100 µF standard
Capacitors
Figure 3-3: 1000 µF capacitor Standard
3.3 Environmental Conditions
3.3.1 Operating Temperature
For optimal accuracy, 1409 models should be used
in an environment of 23°C ±5°C. They should be
allowed to stabilize at those temperatures after any
signi•cant temperature variation.

5
1409 Series
5Operation
3.3.2 Storage Temperature
The 1409 units should be maintained within the
storage temperature range of 0°C to 40°C to retain
its accuracy within the speci•ed limits.
3.4 Shipping and Handling
The 1409 Series should not be exposed to any excessive
shock or temperature extremes.

6
1409 Series
6 Operation

7
1409 Series
7Maintenance
Chapter 4
MAINTENANCE
4.1 Preventive Maintenance
Keep the unit in a clean environment. This will help
prevent possible contamination.
The 1409 is packaged in a closed case, which limits
the entry of contaminants and dust into the instrument.
4.2 Calibration
The 1409 units may be employed as stand-alone in-
struments or as an integral components of a system.
If used as part of a system, they should be calibrated
as part of the overall system to provide an optimum
system calibration.
4.2.1 Calibration Interval
The recommended 1409 Series calibration interval is
twelve (12) months.
The calibration procedure may be carried out by the
user if a calibration capability is available, by IET
Labs, or by a certi!ed calibration laboratory.
If the user should choose to perform this procedure,
then the considerations below should be observed.
4.2.2 General Considerations
It is important, whenever calibrating the 1409 unit,
to be very aware of the capabilities and limitations
of the test instruments used.
Recommended Instruments:
• IET Model 1689 Digibridge (direct
reading)
or
• IET Model 1620 or 1621 Precision
Capacitance Measurement System
(bridge)
The test instruments must be signi!cantly more
accurate than ±0.02% for all ranges, allowing for
a band of uncertainty of the instrument itself.
It is important to allow both the testing instrument
and the 1409 to stabilize for a number of hours at
the nominal operating temperature of 23°C, and at
nominal laboratory conditions of humidity. There
should be no temperature gradients across the unit
under test.

8
1409 Series
8 Maintenance
4.2.3 Calibration Procedure
To calibrate the 1409, proceed as follows
1. Determine and employ proper metrological
practices.
Allow a confidence band for the uncertainty
of the measuring instrument and setup.
2. Set test conditions:
See Calibration conditions in Specifications
Chapter 2 above.
If a Digibridge is used, set to 1 Vrms, series
model.
Calibrated value is the capacitance added
when the standard is plugged into binding
posts.
3. Determine the allowable drift limits for the
capacitance reading.
<0.1% per year
4. Con!rm that the readings fall within these
drift limits, allowing for the uncertainty
band.
If the reading falls outside the limits,the unit
may need to be monitored or returned to
IET,
There are no adjustments in the 1409.
4.3 Replaceable Parts List
Reference IET Pt No Description
132-21 Binding Post, Red
232-20 Binding Post, Black
332-19 Binding Post, Gold
3BP-1000-RED Binding Post, Red
3BP-1000-BLK Binding Post, Black
3BP-1000-GRN Binding Post, Green
Not Shown UG-194 bnc connecor
Not Shown SCA-*-Cap SCA capacitor assembly
Replace * with nominal capacitance value
4
5
6
Figure 4-1 10 µF - 1000 µF Replaceable parts