Associated Research 7704 Operation manual

OPERATION AND SERVICE MANUAL
MODEL 7704
MODEL 7700
Electrical Safety Compliance Analyzers
500VA AC/DC HIPOT WITH INSULATION RESISTANCE TESTER
7704 includes GROUND BOND TESTER
7700 includes CONTINUITY TESTER
STANDARD USB/RS-232 INTERFACE
OPTIONAL IEEE-488 (GPIB)
SERIAL NUMBER
Models
7700/7704
©Associated Research, Inc., 2014
13860 West Laurel Drive
Lake Forest, Illinois, 60045
U.S.A.
Item 38701
Ver 1.16
Printed November 07, 2014

DECLARATION OF CONFORMITY
Manufacturer: Associated Research, Inc.
Address: 13860 W. Laurel Dr.
Lake Forest, IL 60045
USA
Product Name: 7700/7704 Electrical Safety Compliance Analyzer
Model Number: 7700/7704
Conforms to the following Standards:
Safety: IEC 61010-1:2010
IEC 61010-2-030:2010
IEC 61010-031:2002+A1
EN 61010-1:2010
EN 61010-2-030:2010
EN 61010-031:2002
EMC: EN 61326-1:2006
(EN 55011:1998/A2:2002 Class A,
EN 61000-3-2:2006,
EN 61000-3-3:1995/ A1:2001/A2:2005
EN 61000-4-2:1995/A2:2000, EN 61000-4-3:2002,
EN 61000-4-4:2004, EN 61000-4-5:1995/A1:2000,
EN 61000-4-6:2003, EN 61000-4-8:1993/A1:2000,
EN 61000-4-11:2004)
Supplementary Information
The product herewith complies with the requirements of the Low
Voltage Directive 2006/95/EC and the EMC Directive 2004/108/EC.
Last two digits of the year the CE mark was first affixed: 05
The technical file and other documentation are on file with
Associated Research, Inc.
______________________________
Joseph Guerriero
President / General Manager
Associated Research, Inc.
Lake Forest, Illinois USA
November 07, 2014

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TABLE OF CONTENTS
1. Introduction....................................................................................................................1
1.1. Warranty Policies..............................................................................................1
1.2. Safety Symbols.................................................................................................2
1.2.1. Product Marking Symbols.......................................................................2
1.2.2. Caution and Warning Symbols................................................................2
1.3. Glossary of Terms.............................................................................................3
1.4. Safety................................................................................................................4
1.4.1. Service and Maintenance.........................................................................4
1.4.2. Test Station..............................................................................................5
1.4.3. Test Operator...........................................................................................6
1.4.4. Instrument Connections...........................................................................6
1.4.5. Device Under Test...................................................................................7
1.4.6. Key Safety Points to Remember..............................................................7
1.5. Introduction to Product Safety Testing.............................................................8
1.5.1. The Importance of Safety Testing ...........................................................8
1.6. The Different Types of Safety Tests.................................................................8
1.6.1. Principles and Uses of Dielectric Withstand Testing..............................8
1.6.2. Insulation Resistance Test .....................................................................11
1.6.3. Ground Bond Test..................................................................................11
1.7. Key Features and Benefits..............................................................................13
2. Getting Started.............................................................................................................15
2.1. Unpacking and Inspection ..............................................................................15
2.1.1. Packaging...............................................................................................15
2.1.2. Contents of Carton.................................................................................15
2.2. Installation ......................................................................................................15
2.2.1. Work Area .............................................................................................16
2.2.2. Power Requirements..............................................................................16
2.2.3. Basic Connections .................................................................................16
2.2.4. Environmental Conditions.....................................................................17
3. Specifications and Controls ........................................................................................19
3.1. Specifications..................................................................................................19
3.2. Instrument Controls........................................................................................25
3.2.1. Front Panel Controls..............................................................................25
3.2.2. Rear Panel Controls...............................................................................28
3.3. Quickstart........................................................................................................30
4. Operation......................................................................................................................32
4.1. General Operating Procedures........................................................................33
4.1.1. Key Lock Setting...................................................................................33
4.1.2. Memory Configuration..........................................................................34

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4.1.3. Memory Program Selection...................................................................34
4.1.4. Step Selection ........................................................................................35
4.2. Setting Up Test Parameters ............................................................................35
4.2.1. AC Withstand Test Parameter Setting...................................................35
4.2.2. DC Withstand Test Parameter Setting...................................................39
4.2.3. Insulation Resistance Test Setting.........................................................44
4.2.4. Ground Bond test setting model 7704 only...........................................48
4.3. System Parameter Settings .............................................................................52
5. Operating Instructions................................................................................................55
5.1. Setup...............................................................................................................55
5.2. Power-Up........................................................................................................55
5.3. Settings Screen................................................................................................55
5.4. Ground Continuity Test (7700 only) ..............................................................57
5.5. Smart GFI (Ground Fault Interrupt) ...............................................................57
5.6. Reviewing Test Results ..................................................................................58
5.7. Displayed Messages........................................................................................58
5.7.1. Ground Bond Displayed Messages........................................................58
5.7.2. AC Withstand Displayed Messages.......................................................59
5.7.3. DC Withstand Displayed Messages.......................................................61
5.7.4. Insulation Resistance Displayed Messages ...........................................64
6. Remote Control............................................................................................................66
6.1. Signal Outputs on Remote I/O........................................................................66
6.2. Signal Inputs on Remote I/O and Memory.....................................................67
7. Adapter Box Connection.............................................................................................69
8. Bus Remote Interface GPIB / RS-232........................................................................70
8.1. A Brief History of IEEE-488..........................................................................70
8.2. GPIB Messages...............................................................................................70
8.3. Functions.........................................................................................................71
8.4. Signals and Lines............................................................................................71
8.5. GPIB Connector..............................................................................................72
8.6. Interface Functions .........................................................................................72
8.7. GPIB Address.................................................................................................73
8.8. RS-232 Interface.............................................................................................73
8.9. Interface Bus Command List..........................................................................75
8.10. GPIB Service Request ..................................................................................78
8.11. Example of communicating over the IEEE bus............................................79
8.12. Non Volatile Memory...................................................................................79
9. Options..........................................................................................................................80
10. Calibration Procedure...............................................................................................89
10.1. Calibration Initialization...............................................................................89
10.2. Security Settings...........................................................................................89
10.2.1. Password Setting..................................................................................89

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10.2.2. Memory Lock selection.......................................................................89
10.3. Calibration Points .........................................................................................90
10.3.1. Calibration of AC Hipot Voltage.........................................................90
10.3.2. Calibration of DC Hipot Voltage.........................................................90
10.3.3. Calibration of IR DC Voltage..............................................................91
10.3.4. Calibration of AC 100mA Range........................................................91
10.3.5. Calibration of DC 10mA Range..........................................................92
10.3.6. Calibration of AC 3.5mA Range.........................................................92
10.3.7. Calibration of DC 3500A Range.......................................................93
10.3.8. Calibration of DC 350A Range.........................................................93
10.3.9. Calibration of IR XXX.XMrange....................................................94
10.3.10. Calibration of IR XXXXMrange...................................................94
10.3.11. Calibration of Ground Bond AC Voltage (Model 7704 only)...........94
10.3.12. Calibration of Ground Bond AC Current (Model 7704 only)...........95
10.3.13. Calibration of Real Current for units with option 51 only ................95
11. Replacement Parts List .............................................................................................97
Index is located at the back of the manual

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1. Introduction
1.1. Warranty Policies
Associated Research, Inc., certifies that the instrument listed in this manual meets or exceeds
published manufacturing specifications. This instrument was calibrated using standards that
are traceable to the National Institute of Standards and Technology (NIST).
Your new instrument is warranted to be free from defects in workmanship and material for a
period of (2) year from date of shipment. You must complete the on-line registration at
www.asresearch.com/register or call 1-800-858-TEST ext. 0 to register over the phone
5-Year Program
All Associated Research instruments include the opportunity to extend the standard warranty
for up to a period of 5 years. Returning instruments to Associated Research for their annual
calibration and inspection will extend the instrument's warranty for an additional year. This
warranty is extendable for up to five years and annual returns must be made in succession
starting one year after the original purchase date. There are no additional costs for the 5 year
product warranty. The only annual costs to the customer are the standard calibration fees and
shipping costs. This extended warranty is non-transferable and is offered only to the original
purchaser. A return material authorization (RMA) must be obtained from AR before returning
this instrument for warranty service. Please contact our Customer Support Center at 1-800-
858-TEST (8378) to obtain an RMA number. It is important that the instrument is packed
properly for safe transport. Please contact our customer support center for proper instructions
on packaging. Damages sustained as a result of improper packaging will not be honored.
Transportation costs for the return of the instrument for warranty service must be prepaid by
the customer. AR will assume the return freight costs when returning the instrument to the
customer. The return method will be at the discretion of Associated Research.
3-Year Program
A 3-Year warranty is also available for instruments purchased and used in North America. All
costs for this warranty are paid with the initial purchase and include warranty coverage, annual
calibration and standard ground return freight for three years. However, unlike our 5-year
program annual calibration and inspection by Associated Research is not required.
Except as provided herein, Associated Research makes no warranties to the purchaser of this
instrument and all other warranties, express or implied (including, without limitation,
merchantability or fitness for a particular purpose) are hereby excluded, disclaimed and
waived.
Any non-authorized modifications, tampering or physical damage will void your warranty.
Elimination of any connections in the earth grounding system or bypassing any safety systems
will void this warranty. This warranty does not cover batteries or accessories not of Associated
Research manufacture. Parts used must be parts that are recommended by AR as an acceptable
specified part. Use of non-authorized parts in the repair of this instrument will void the
warranty.

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1.2. Safety Symbols
1.2.1. Product Marking Symbols
Product will be marked with this symbol when it is necessary to refer to the
operation and service manual in order to prevent injury or equipment damage.
Product will be marked with this symbol when hazardous voltages may be present.
Product will be marked with this symbol at connections that require earth
grounding.
1.2.2. Caution and Warning Symbols
Calls attention to a procedure, practice, or condition that could possibly
cause bodily injury or death.
Calls attention to a procedure, practice, or condition that could possibly
cause damage to equipment or permanent loss of data.

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1.3. Glossary of Terms (As used in this manual)
Alternating Current, AC: Current that reverses direction on a regular basis, commonly in the U.S.A. 60
per second, in other countries 50 times per second.
Breakdown: The failure of insulation to effectively prevent the flow of current sometimes evidenced by
arcing. If voltage is gradually raised, breakdown will begin suddenly at a certain voltage level. Current flow is
not directly proportional to voltage. Once breakdown current has flown, especially for a period of time, the next
gradual application of voltage will often show breakdown beginning at a lower voltage than initially.
Conductive: Having a volume resistivity of no more than 103 ohm-cm or a surface resistivity of no more than
105 ohms per square.
Conductor: A solid or liquid material which has the ability to let current pass through it, and which has a
volume resistivity of no more than 103 ohm-cm.
Current: The movement of electrons through a conductor. Current is measured in amperes, milliamperes,
microamperes, nanoamperes, or picoamperes. Symbol = I
Dielectric: An insulating material that is positioned between two conductive materials in such a way that a
charge or voltage may appear across the two conductive materials.
Direct Current, DC: Current that flows in one direction only. The source of direct current is said to be
polarized and has one terminal that is always at a higher potential than the other.
Hipot Tester: Common term for dielectric-withstand test equipment.
Hypot®: Registered trademark of Associated Research, Inc., for its dielectric-withstand test equipment.
Insulation: Gas, liquid or solid material which has a volume resistivity of at least 1012 ohm-cm and is used
for the purpose of resisting current flow between conductors.
Insulation Resistance Tester: An instrument or a function of an instrument capable of measuring
resistance's in excess of 200 megohms. Usually employs a higher voltage power supply than used in ohmmeters
measuring up to 200 megohms.
Leakage: AC or DC current flow through insulation and over its surfaces, and AC current flow through a
capacitance. Current flow is directly proportional to voltage. The insulation and/or capacitance are thought of as
a constant impedance, unless breakdown occurs.
Resistance: That property of a substance that impedes current and results in the dissipation of power, in the
form of heat. The practical unit of resistance is the ohm. Symbol = R
Trip Point: A minimum or maximum parameter set point that will cause an indication of unacceptable
performance during a run test.
Voltage: Electrical pressure, the force which causes current through an electrical conductor.
Symbol = V

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1.4. Safety
This product and its related documentation must be reviewed for familiarization with safety
markings and instructions before operation.
This product is a Safety Class I instrument (provided with a protective earth terminal).
Before applying power verify that the instrument is set to the correct line voltage (110 or 220)
and the correct fuse is installed.
A Hipot produces voltages and currents that can cause harmful or
fatal electric shock. To prevent accidental injury or death, these
safety procedures must be strictly observed when handling and using
the test instrument.
1.4.1. Service and Maintenance
User Service
To prevent electric shock do not remove the instrument cover. There are no user serviceable
parts inside. Routine maintenance or cleaning of internal parts is not necessary. Avoid the use
of cleaning agents or chemicals on the instrument, some chemicals may damage plastic parts or
lettering. Any external cleaning should be done with a clean dry or slightly damp cloth.
Schematics, when provided, are for reference only. Any replacement cables and high voltage
components should be acquired directly from Associated Research, Inc. Refer servicing to an
Associated Research, Inc. authorized service center.
ASSOCIATED RESEARCH, INC.
13860 WEST LAUREL DRIVE
LAKE FOREST, IL 60045-4546 U.S.A.
PHONE: [phone]
1 (800) 858-TEST (8378)
FAX: [phone]
E-MAIL : [email protected]
www.asresearch.com
Service Interval
The instrument, its power cord, test leads, and accessories must be returned at least once a year
to an Associated Research authorized service center for calibration and inspection of safety
related components. Associated Research will not be held liable for injuries suffered if the
instrument is not properly maintained and safety checked annually.
User Modifications
Unauthorized user modifications will void your warranty. Associated Research will not be
responsible for any injuries sustained due to unauthorized equipment modifications or use of
parts not specified by Associated Research. Instruments returned to Associated Research with
unsafe modifications will be returned to their original operating condition at the customers
expense.

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1.4.2. Test Station
Location
Select an area away from the main stream of activity which employees do not walk through in
performing their normal duties. If this is not practical because of production line flow, then the
area should be roped off and marked for HIGH VOLTAGE TESTING. No employees other
than the test operators should be allowed inside.
If benches are placed back-to-back, be especially careful about the use of the bench opposite
the test station. Signs should be posted: "DANGER - HIGH VOLTAGE TEST IN
PROGRESS - UNAUTHORIZED PERSONNEL KEEP AWAY."
Work Area
Perform the tests on a non-conducting table or workbench, if possible. If you cannot avoid
using a conductive surface, be certain that it is connected to a good earth ground and the high
voltage connection is insulated from the grounded surface.
There should not be any metal in the work area between the operator and the location where
products being tested will be positioned. Any other metal in the work area should be
connected to a good ground, never left "floating".
Position the tester so the operator does not have to reach over the product under test to activate
or adjust the tester. If the product or component being tested is small, it may be possible to
construct guards or an enclosure around the device to be tested. Construct the guards of a non-
conducting material such as clear acrylic, so that the item being tested is within the guards or
enclosure during the test. If possible, the guards or enclosure should also contain safety
switches that will not allow the tester to operate unless the guards are in place or the enclosure
closed.
Keep the area clean and uncluttered. All test equipment and test leads not necessary for the
test should be removed from the test bench and put away. It should be apparent to both the
operator and to any observers, the product that is being tested and the product that is waiting to
be tested, or has already been tested.
Do not perform Hipot tests in a combustible atmosphere or in any area where combustible
materials are present.
Power
Dielectric Voltage-Withstand Test Equipment must be connected to a good ground. Be certain
that the power wiring to the test bench is properly polarized and that the proper low resistance
bonding to ground is in place.
Power to the test station should be arranged so that it can be shut off by one prominently
marked switch located at the entrance to the test area. In case of an emergency, anyone can cut
off the power before entering the test area to offer assistance.

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1.4.3. Test Operator
Qualifications
This instrument generates voltages and currents that can cause harmful or fatal electric shock
and must only be operated by a skilled worker trained in its use.
The operator should understand the electrical fundamentals of voltage, current, and resistance.
They should recognize that the test instrument is a variable high-voltage power supply with the
return circuit directly connected to earth ground, therefore, current from the high-voltage
output will flow through any available ground path.
Rules
Operators should be thoroughly trained to follow all of the aforementioned rules, in addition to
any other applicable safety rules and procedures. Defeating any safety system should be
considered a serious offense with severe penalties such as removal from the Hipot testing job.
Allowing unauthorized personnel in the area during a test should also be dealt with as a serious
offense.
Dress
Operators should not wear jewelry that could accidentally complete a circuit.
Medical Restrictions
Personnel with heart ailments or devices such as pacemakers should be informed that the
voltages and currents generated by the instrument are very dangerous. If contacted it may
cause heart-related problems that a person of good health may not experience. Please have the
test operator consult their physician for recommendations.
1.4.4. Instrument Connections
Never perform a hipot test on energized circuitry or equipment.
The instrument is equipped with a safety ground connection, be sure that this is
connected to a good earth ground.
Always connect the return lead first, regardless of whether the item under test is a sample of
insulating material, a component tested with the high voltage test lead, or a cord-connected
device with a two or three prong plug. The return lead should be connected first for any type
of hipot testing.
Plug in the high voltage test lead only when it is being used. Handle its clip only by the
insulator---never touch the clip directly. Be certain that the operator has control over any
remote test switches connected to the Hipot. Double check the return and high voltage
connections from the Hipot and the Line, Neutral, Ground and Case connections from the Line
Leakage tester to be certain that they are proper and secure.

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1.4.5. Device Under Test
Do not touch the device under test, high voltage test lead, alligator
clip, or clip insulator once the test has been started.
Do not touch the front panel when testing or after a malfunction
has occurred.
When testing with DC, always discharge the capacitance of the item under test and anything
the high voltage may have contacted--such as test fixtures--before handling it or disconnecting
the test leads.
HOT STICK probes can be used to discharge any capacitance in the device under test as a
further safety precaution. A hot stick is a non-conducting rod about two feet long with a metal
probe at the end that is connected to a wire. To discharge the device under test, two hot sticks
are required. First, connect both probe wires to a good earth ground. Then touch one probe tip
to the same place that the return lead was connected. While holding the first probe in place,
touch the second probe tip to the same place where the high voltage lead was connected.
1.4.6. Key Safety Points to Remember
Keep unqualified and unauthorized personnel away from the test area.
Arrange the test station in a safe and orderly manner.
Never touch the product or connections during a test.
In case of any problem, turn off the high voltage first.
Properly discharge any item tested with DC before touching connections.

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1.5. Introduction to Product Safety Testing
1.5.1. The Importance of Safety Testing
Product Safety Tests are specified during the design and development stages of a product as
well as in the production of the products to insure that it meets basic safety requirements.
These tests are designed to verify the safety of the electrical products in that they do not
jeopardize the safety of the people, domestic animals, and property of anyone who may come
in contact with these products. In an era of soaring liability costs, original manufacturers of
electrical and electronic products must make sure every item is as safe as possible. All
products must be designed and built to prevent electric shock, even when users abuse the
equipment or by-pass built in safety features.
To meet recognized safety standards, one common test is the "dielectric voltage-withstand
test". Safety agencies which require compliance safety testing at both the initial product design
stage and for routine production line testing include: Underwriters Laboratories, Inc. (UL), the
Canadian Standards Association (CSA), the International Electrotechnical Commission (IEC),
the British Standards Institution (BSI), the Association of German Electrical Engineers (VDE)
and (TÜV), the Japanese Standards Association (JSI). These same agencies may also require
that an insulation resistance test and high current ground bond test be performed.
1.6. The Different Types of Safety Tests
1.6.1. Dielectric Withstand Test
The principle behind a dielectric voltage - withstand test is simple. If a product will function
when exposed to extremely adverse conditions, it can be assumed that the product will function
in normal operating circumstances.
Common Applications of the Dielectric Withstand Test:
Design (performance) testing: Determining design adequacy to meet service conditions.
Production Line testing: Detecting defects in material or workmanship during processing.
Acceptance testing: Proving minimum insulation requirements of purchased parts.
Repair Service testing: Determine reliability and safety of equipment repairs.
The specific technique used to apply the dielectric voltage - withstand test to each product is
different. During a dielectric voltage - withstand test, an electrical device is exposed to a
voltage significantly higher than it normally encounters, for a specified duration of time.
During the test, all current flow from the high voltage output to the return is measured. If,
during the time the component is tested, the current flow remains within specified limits, the
device is assumed safe under normal conditions. The basic product design and use of the
insulating material will protect the user against electrical shock.
The equipment used for this test, a dielectric-withstand tester, is often called a "hipot" (for high
potential tester). The "rule of thumb" for testing is to subject the product to twice its normal

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operating voltage, plus 1,000 volts.
However, specific products may be tested at much higher voltages than 2X operating voltages
+ 1,000 volts. For example, a product designed to operate in the range between 100 to 240
volts can be tested between 1,000 to 4,000 volts or higher. Most "double insulated" products
are tested at voltages much higher than the "rule of thumb".
Testing during development and prototype stages is more stringent than production run tests
because the basic design of the product is being evaluated. Design tests usually are performed
on only a few samples of the product. Production tests are performed on every item as it
comes off the production line.
The hipot tester must also maintain an output voltage between 100% and 120% of
specification. The output voltage of the hipot must have a sinusoidal waveform with a
frequency between 40 to 70 Hz and has a peak waveform value that is not less than 1.3 and not
more than 1.5 times the root-mean-square value.
Types of Failures only detectable with a Hipot test
Weak Insulating Materials
Pinholes in Insulation
Inadequate Spacing of Components
Pinched Insulation
Dielectric Withstand Test; AC verses DC
Please check with the Compliance Agency you are working with to see which of the two types
of voltages you are authorized to use. In some cases, a Compliance Agency will allow either
AC or DC testing to be done. However, in other cases the Compliance Agency only allows for
an AC test. If you are unsure which specification you must comply with please contact our
CUSTOMER SUPPORT GROUP at 1-800-858-TEST (8378).
Many safety agency specifications allow either AC or DC voltages to be used during the hipot
test. When this is the case, the manufacturer must make the decision on which type of voltage
to utilize. In order to do this it is important to understand the advantages and the disadvantages
of both AC and DC testing.
AC testing characteristics
Most items that are hipot tested have some amount of distributed capacitance. An AC voltage
cannot charge this capacitance so it continually reads the reactive current that flows when AC
is applied to a capacitive load.

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AC testing advantages
AC testing is generally much more accepted by safety agencies than DC testing. The main
reason for this is that most items being hipot tested will operate on AC voltages. AC hipot
testing offers the advantage of stressing the insulation alternately in both polarities, which
more closely simulates stresses the product will see in real use.
Since AC testing cannot charge a capacitive load the current reading remains consistent from
initial application of the voltage to the end of the test. Therefore, there is no need to gradually
bring up the voltage since there is no stabilization required to monitor the current reading.
This means that unless the product is sensitive to a sudden application of voltage the operator
can immediately apply full voltage and read current without any wait time.
Another advantage of AC testing is that since AC voltage cannot charge a load there is no need
to discharge the item under test after the test.
AC testing disadvantages
One disadvantage of AC testing surfaces when testing capacitive products. Again, since AC
cannot charge the item under test, reactive current is constantly flowing. In many cases, the
reactive component of the current can be much greater than the real component due to actual
leakage. This can make it very difficult to detect products that have excessively high leakage
current.
Another disadvantage of AC testing is that the hipot has to have the capability of supplying
reactive and leakage current continuously. This may require a current output that is actually
much higher than is really required to monitor leakage current and in most cases is usually
much higher than would be needed with DC testing. This can present increased safety risks as
operators are exposed to higher currents.
DC testing characteristics
During DC hipot testing the item under test is charged. The same test item capacitance that
causes reactive current in AC testing results in initial charging current which exponentially
drops to zero in DC testing.
DC testing advantages
Once the item under test is fully charged, the only current flowing is true leakage current. This
allows a DC hipot tester to clearly display only the true leakage of the product under test.
Another advantage to DC testing is that the charging current only needs to be applied
momentarily. This means that the output power requirements of the DC hipot tester can
typically be much less than what would be required in an AC tester to test the same product.
DC testing disadvantages
Unless the item being tested has virtually no capacitance, it is necessary to raise the voltage
gradually from zero to the full test voltage. The more capacitive the item the more slowly the
voltage must be raised. This is important since most DC hipots have failure shut off circuitry

11
which will indicate failure almost immediately if the total current reaches the leakage threshold
during the initial charging of the product under test.
Since a DC hipot does charge the item under test, it becomes necessary to discharge the item
after the test.
DC testing unlike AC testing only charges the insulation in one polarity. This becomes a
concern when testing products that will actually be used at AC voltages. This is an important
reason that some safety agencies do not accept DC testing as an alternative to AC.
When performing AC hipot tests the product under test is actually tested with peak voltages
that the hipot meter does not display. This is not the case with DC testing since a sinewave is
not generated when testing with direct current. In order to compensate for this most safety
agencies require that the equivalent DC test be performed at higher voltages than the AC test.
The multiplying factor is somewhat inconsistent between agencies which can cause confusion
concerning exactly what equivalent DC test voltage is appropriate.
1.6.2. Insulation Resistance Test
Some "dielectric analyzers today come with a built in insulation resistance tester. Typically,
the IR function provides test voltages from 500 to 1,000 volts DC and resistance ranges from
kilohms to gigaohms. This function allows manufacturers to comply with special compliance
regulations. BABT, TÜV and VDE are agencies that may under certain conditions, require an
IR test on the product before a Hipot test is performed. This typically is not a production line
test but a performance design test.
The insulation resistance test is very similar to the hipot test. Instead of the go/no go indication
that you get with a hipot test the IR test gives you an insulation value usually in Megohms.
Typically, the higher the insulation resistance value the better the condition of the insulation.
The connections to perform the IR test are the same as the hipot test. The measured value
represents the equivalent resistance of all the insulation which exists between the two points
and any component resistance which might also be connected between the two points.
Although the IR test can be a predictor of insulation condition it does not replace the need to
perform a dielectric withstand test.
1.6.3. Ground Bond Test
The Ground Bonding test determines whether the safety ground circuit of the product under
test can adequately handle fault current if the product should ever become defective. A low
impedance ground system is critical in ensuring that in case of a product failure, a circuit
breaker on the input line will act quickly to protect the user from any serious electrical shock.
International compliance agencies such as CSA, IEC, TÜV, VDE, BABT and others, have
requirements calling out this test. This test should not be confused with low current continuity
tests that are also commonly called out in some safety agency specifications. A low current
test merely indicates that there is a safety ground connection. It does not completely test the
integrity of that connection.

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Compliance agency requirements vary on how different products are to be tested. Most
specifications call for test currents of between 10 and 40 amps. Test voltages at these currents
are typically required to be less than 12 volts. Maximum allowable resistance readings of the
safety ground circuit are normally between 100 and 200 milliohms.
If you are testing a product that is terminated in a three-prong plug, you are required to perform
a continuity or ground bond test on the ground conductor to the chassis or dead metal of the
product.
IF YOU SHOULD HAVE ANY QUESTIONS RELATING TO THE OPERATION OF
YOUR INSTRUMENT CALL 1-800-858-TEST(8378) IN THE U.S.A.