Ground Bond – IEC 60335 / IEC 62368 / IEC 61010

What Is Ground Bond — IEC 60335?

The ground bond test is a test in which connection resistance is measured by applying high current between the protective earth terminal and accessible metal parts. It shows that fault current can flow safely.

Purpose of Ground Bond — IEC 60335

The purpose is to verify that, under a fault condition, leakage current can flow through the protective conductor at low resistance to trip the protective device.

Which Products Is Ground Bond — IEC 60335 Applied To?

Class I electrical appliances
Machinery and panel installations
Electric hand tools
White goods
Laboratory instruments

In Which Sectors Is Ground Bond — IEC 60335 Used?

ElectricalElectronicsMachineryMedical Device

Standards Related to Ground Bond — IEC 60335

IEC 60335Safety in home and similar electrical devices test
IEC 62368Security in audio, video and information technology devices test
IEC 61010Safety in measuring, control and laboratory devices test

Ground Bond — IEC 60335 Conditions

Test current: Defined in the product standard; typically 10 A – 25 A, or a multiple of rated current
Time: Defined in the standard; typically 60 s, or a short-duration application
Acceptance limit: Maximum resistance defined in the product standard (typically on the order of 0.1 Ω)
Measurement points: All accessible metal parts

Equipment for Ground Bond — IEC 60335

Ground bond tester
Four-wire measurement connection
Probe and clamp set
Calibration shunt

Sample Requirements for Ground Bond — IEC 60335

All accessible metal parts must be determined
Care must be taken at painted and coated contact points
The insulation class must be documented
The effect of connection resistance on the measurement must be separated out

Duration of Ground Bond — IEC 60335

Depends on the number of measurement points; typically half a working day.

Ground Bond — IEC 60335 Procedure

1Accessible metal parts are determined.
2Test current and duration are set per the product standard.
3Current is applied between each point and the earth terminal.
4Resistance is calculated from the voltage drop.
5Results are compared with the limit.

Ground Bond — IEC 60335 Acceptance Criteria

The acceptance criterion is the maximum resistance value in the product standard. Exceeding the limit indicates an inadequate earth connection.

Evaluation of Results

Probe contact resistance can distort the result; a four-wire measurement and a clean contact surface are critical.

Ground Bond — IEC 60335 Report

Standard applied
Test current and duration
Measurement points
Measured resistances and limit

Accreditation

EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.

Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.

Scope and authorisations

Related Regulations

LVD 2014/35/EU
Machinery Directive

Electrical Safety — What Does This Testing Field Cover?

The section below describes the field that the Ground Bond test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.

Electrical safety testing shows that a device poses no risk of electric shock, fire or injury to the user in normal use and under foreseeable fault conditions. This family is the test group most often requested when a product enters the market; almost every electrically operated product passes through this gate.

The logic of the field rests on a single assumption: FAULTS WILL HAPPEN. Insulation will age, a component will short, a cable will break, the user will misuse the device. Standards therefore test not only normal operation but also single fault conditions. The sentence "the device works correctly" is not evidence in this field; the evidence is that the device stays safe when it fails.

Assessment addresses three layers together. In the constructional layer, insulation distances (creepage and clearance), protective barriers, earthing continuity, enclosure strength and component selection are examined — this layer is largely a matter of inspection and measurement rather than testing. In the electrical layer, dielectric strength, leakage current, insulation resistance and behaviour under fault conditions are measured. In the thermal layer, temperature rise in normal and abnormal operation is monitored; an overheating component is both a fire risk and a risk of insulation breakdown.

Which standard applies is determined by WHAT THE PRODUCT IS, and that decision affects the entire outcome. Household appliances fall under the IEC 60335 series, information technology and audio/video products under IEC 62368-1, measurement and laboratory equipment under IEC 61010-1, and medical devices under IEC 60601-1. A report obtained under the wrong standard is not accepted in the file even if the measurements it contains are correct.

Component conformity is often overlooked in this field. The safety of the device rests on the conformity of the transformer, optocoupler, fuse, switch and power supply it uses. The list of critical components and the certification status of each is part of the technical file; a change of component reopens the safety assessment.

Method groups in this field

Constructional examination
Insulation distances, barriers, earthing arrangement, accessibility and selection of critical components are examined. It comes before testing and many non-conformities are caught here.
Dielectric strength
It is verified that the insulation withstands the defined voltage. It must not be confused with the routine test on the production line; the type test is more severe.
Leakage current and earthing
The current that could reach the user is measured; the continuity and resistance of the protective earthing path are verified.
Heating tests
Temperatures of components, windings and accessible surfaces are measured in normal and abnormal operation.
Fault condition tests
Components are deliberately short-circuited or open-circuited; the appliance is expected not to cause a fire and not to make a hazardous part accessible.
Mechanical and enclosure tests
Impact, drop, strain relief, IP protection and the safety of moving parts are assessed.

Commonly confused in this field

A CB certificate is not a CE declaration. CB is the output of a mutual recognition arrangement that eases national certification; the CE declaration is made by the manufacturer under its own responsibility.
A part of IEC 60335 is not sufficient on its own; it is applied together with Part 1.
IEC 60950-1 and IEC 60065 have been withdrawn. Old certificates based on these codes cannot be used in a current file.
Separate certification of the adapter does not cover the conformity of the device; the device is assessed as the system it forms together with its power supply.
A change of critical component (transformer, fuse, optocoupler supplier) is not a silent change; it requires the safety file to be reviewed.

Which decisions these results support

CE declaration under the Low Voltage Directive
IECEE CB certificate and entry into national certification schemes
Assessing the safety impact of design changes
Establishing and maintaining the critical component list
Responding to market surveillance requests

Related Tests

Frequently Asked Questions About Ground Bond — IEC 60335

According to which standard is Ground Bond made?

Ground Bond is executed in scope IEC 60335-1, IEC 60204-1, IEC 62368-1, IEC 61010-1, IEC 60335, IEC 62368 and IEC 61010. The limit values and acceptance criteria to be applied are defined in the product standard; The version valid for your product is confirmed in writing at the offer stage.

Which products does Ground Bond apply to?

Mainly applied to Class I electrical appliances, Machinery and panel installations, Electric hand tools, White goods and Laboratory instruments. Whether your product is included in the scope is determined by examining its technical specifications and intended use.

Under what conditions is Ground Bond done?

The determining parameters are: Test current — Defined in the product standard; typically 10 A – 25 A, or a multiple of rated current, Time — Defined in the standard; typically 60 s, or a short-duration application and Acceptance limit — Maximum resistance defined in the product standard (typically on the order of 0.1 Ω). The full terms are in the "Test Conditions" section on the page and vary depending on the product standard.

What kind of sample is needed for Ground Bond?

All accessible metal parts must be determined, Care must be taken at painted and coated contact points and The insulation class must be documented. The number of samples is determined according to the product standard and the scope to be reported.

How long does Ground Bond take?

Depends on the number of measurement points; typically half a working day. This duration belongs to the experiment itself; sample preparation, queuing and reporting are also evaluated. A realistic schedule for your product is given in the offer.

What is the Ground Bond result called "appropriate"?

The acceptance criterion is the maximum resistance value in the product standard. Exceeding the limit indicates an inadequate earth connection.