IEC 61587 5 Edition 1 0 2013 12 INTERNATIONAL STANDARD NORME INTERNATIONALE Mechanical structures for electronic equipment – Tests for IEC 60917 and IEC 60297 – Part 5 Seismic tests for chassis, subra[.]
General
The parameters such as time history, zero period acceleration, damping ratio, and severities
(frequency range, required response spectrum, acceleration per axis) have been derived from methods stated in IEC 60068-3-3, IEC 60068-2-57 and environment zone 4 as defined in
General conditions
The seismic tests will utilize a synthesized waveform, conducted under either single-axis or tri-axis conditions as specified in the standard The duration of the strong segment of the time history is determined from the moment the plot first reaches 25% of its maximum value until it last decreases.
25 % level d) The TRS (Test Response Spectrum) shall equal or exceed the RRS (Required Response
The damping ratio of 2% or 3% is utilized to assess the TRS and RRS, excluding the frequency range below 0.5 Hz and above 50 Hz Additionally, the standard acceleration due to gravity (g) is rounded to the nearest whole number.
The test waveform must meet the requirements of the RRS It is permissible for the TRS to be lower than the RRS, particularly within the frequency range below half or above twice the first natural frequency, but it should not exceed 20% of the RRS.
If the TRS fails to comply with the RRS due to the vibration table's displacement limitations, it must operate within a frequency range of 1 Hz or higher.
Single-axis acceleration
The vibration table must have each axis accelerated independently, with acceleration measurements taken during the test as outlined in sections 6.2.7 b) and 6.3.6 b) The strong portion of the time history should last at least 18 seconds, and the zero period acceleration of the input test wave must be set at 16 m/s², following the RRS as shown in Figure 1 Additionally, the time history of the test wave is detailed in Figure 2.
A cc el er at ion (m /s 2 )
Figure 1 – RRS for the test wave (single-axis acceleration)(damping ratio 2,0 %)
Figure 2 – Time history of the test wave (single-axis acceleration)
Tri-axial acceleration
The vibration table must be accelerated along all three axes simultaneously, with varying acceleration levels for each axis as specified in sections 6.2.7 b) and 6.3.6 b) The strong part of the time history should last at least 30 seconds For the input test waveform, the maximum required acceleration is 12 m/s² for horizontal movement and 6 m/s² for vertical movement, as illustrated in Figure 3 Additionally, Figure 4 provides examples of the time history for each axis.
A cc el er at ion (m /s 2 )
0,1 1 10 100 b) Up-and-down A cc el er at ion (m /s 2 )
Figure 3 – RRS for the test wave (tri-axial acceleration)(damping ratio 3 %)
A cc el er ar tion (m /s 2 ) 8
A cc el er ar tion (m /s 2 ) 8
A cc el er ar tion (m /s 2 )
Figure 4 – Time history of the test wave for each axis (tri-axial acceleration)
Specimen monitoring
a) The functionality of the chassis, subrack or plug-in unit (in accordance to IEC 61587-1,
Before and after the seismic test, it is essential to monitor the intended use as outlined in IEC 61587-3 Additionally, the structural and mechanical condition of the chassis, subrack, or plug-in unit must be verified before and after testing Optional Low Level Contact Resistance (LLCR) testing may also be conducted for further assessment.
6.2.9) monitoring instrumentation shall respond at a rate that is adequate to detect intermittent malfunctions during testing Intermittent malfunctioning time, if acceptable, is considered application specific.
Seismic simulation
The chassis, subrack, or plug-in unit must undergo vibration tests across three axes: longitudinal, transverse, and vertical, as well as seismic simulation tests using a reference waveform The resultant Test Response Spectrum (TRS) will be evaluated to ensure it meets or exceeds the Required Response Spectrum (RRS) within the frequency range of 1.0 Hz to 50 Hz Additionally, the TRS should not surpass the RRS by more than 30% in the amplified region of 3.0 Hz to 7.0 Hz to avoid over-testing of the components.
6 Test setup and parts to be monitored
General
Seismic testing of the chassis, subrack, or plug-in unit must be conducted under intended use and simulated load conditions to evaluate the structural and mechanical integrity of each component individually.
Category A – Plug-in units
General
Plug-in units according to IEC 60917 and IEC 60297 series interface with the subrack or chassis with integrated subrack Plug-in units occupy a corresponding position (also called a
To perform a seismic test on a single plug-in unit, it is essential to replicate the corresponding subrack position and interface conditions in the intended use subrack The guide features of the plug-in unit within the subrack must align with the intended use conditions, including guide width, depth, rigidity, and material.
• The subrack or chassis shall be pre-qualified to Clause 4 of this standard and comply with
The plug-in unit being tested must have the appropriate intended use free connector connected, while the corresponding fixed connector should be securely attached to the subrack or chassis in accordance with its intended use.
The plug-in unit being tested must be placed in the central slot of the subrack and secured using the designated retention devices, tightened to the specified torque values, as illustrated in Figures 7, 8, and 9.
• The subrack or chassis with integrated subrack test fixture shall be rigid, see Figures 7, 8 and 9 The test fixture shall be designed using the practices outlined in IEC 60068-2-47.
Plug-in unit simulated load
The simulated mass of a plug-in unit, as outlined in Clause 4, Categories A1 to A4, encompasses both the mass of the plug-in unit itself and the additional simulated load, reflecting its intended use.
To test a plug-in unit, it must be loaded with a simulated mass that reflects the worst-case scenario, as illustrated in Figure 5 for intended use A (discrete distribution of simulated load) and Figure 6 for intended use B (compact distribution of simulated load).
• The simulated load shall be attached to the plug-in unit PB without loosening during the test
• Single or multiple free connectors shall be placed according to their mechanical and electrical mounting features and according to the intended use of the plug-in unit
• Input and output cable(s) on the plug-in unit front panel shall be attached at their end(s) to the test fixture without loosening during the test
• Intended use plug-in unit covers shall be attached
To secure the plug-in unit within the test chassis or subrack during testing, retention screws must be utilized These screws should be tightened to the specified torque values for optimal performance.
Input/output cable(s) Length 254 mm End attached to the test fixture Simulated load
Intended use plug-in unit covers
Plug-in unit front panel Plug-in unit retention
Figure 5 – Plug-in unit intended use A load distribution (discrete)
Input/output cable(s) Length 254 mm End attached to the test fixture Simulated load
Plug-in unit front panel Plug-in unit retention
Figure 6 – Plug-in unit intended use B load distribution (compact)
Plug-in unit test setup onto the test fixture
The plug-in unit to be tested shall use a 6.2 intended use and pre-qualified subrack or chassis with integral subrack, mounted onto the vibration table using a rigid fixture
Mounting condition is referred to in IEC 60068-2-6, in which there is a reference to
The test fixture must be designed in accordance with IEC 60068-2-47 standards, ensuring a minimum of 1U (as per IEC 60297) or 1SU (according to IEC 60917) of free space above and below the test specimen, as illustrated in Figures 7 and 8.
• The plug-in unit under test shall be mounted into the centre slot of the intended use chassis or subrack (with worst condition in mind)
• Filler panels (any type or size) shall be attached to close any open slot positions in the pre-qualified subrack or chassis
• The choice of pretested chassis or subrack and filler panels shall comply with the type of plug-in unit under test (non-EMC or EMC)
• The plug-in unit under test and the filler panel retention screws shall be tightened to their recommended torque values
• Input and output cable(s) on the plug-in unit front panel under test shall be attached at their end(s) to the test fixture without loosening during the test
• The test fixture shall have at least 1U (per IEC 60297) or 1SU (per IEC 60917) free space above and below the chassis or subrack to be tested
1U or 1SU min n × U or n × SU
Centre positioned plug-in unit with simulated load under test
I/O cable attachment Subrack pre-qualified per 6.2 IEC 2887/13
Figure 7 – Plug-in unit test setup – Subrack
Centre positioned plug-in unit with simulated load under test
1U or 1SU min n × U or n × SU
Subrack integrated Chassis pre-qualified per 6.2 z x y
Figure 8 – Plug-in unit test setup – Chassis with integrated subrack
Plug-in unit test fixture setup to the vibration table
Mounting condition is referred to in IEC 60068-2-6, in which there is a reference to
The chassis or subrack test fixture is to be attached to the vibration table via bolts, see Figure
Motor actuator and Vibration table
Acceleration monitor Displacement transducer Subrack/chassis pre-qualified per 6.2
Plug-in unit under test Front panel z y x
Plug-in unit under test
Figure 9 – Block diagram of the plug-in unit test setup
Plug-in unit mechanical parts under test
• Overall mechanical construction of the plug-in unit
• Guidance feature (guide rail) of the subrack
• Subrack retention device of the plug-in unit
• Plug-in unit mechanical hot-swap functionality
• Free connector/fixed connector mechanical reliability according to connector of choice standard or specification
• Free connector/fixed connector electrical (LLCR) reliability (optional) See 6.2.9
• Earth bond continuity See IEC 61587-1
• ESD contact interface to the Subrack See IEC 60297-3-101
• EMC contact mechanical reliability See IEC 61587-3.
Vibration response monitoring
The control accelerometer must be installed on the front panel of the plug-in unit, which should be positioned in the center slot of the subrack Refer to Figures 7, 8, and 9 for visual guidance.
Plug-in unit measurements
The following measurements must be reported: a) the critical frequency and damping ratio of the plug-in unit under test, assessed through sinusoidal or random waveform sweeps before and after the seismic test; b) the acceleration of the vibration table during testing; c) the acceleration of the plug-in unit; and d) the Low Level Contact Resistance (LLCR) as per IEC 60512-2-1, which can be measured before, after, and/or during the test as an optional step.
Test sequence
• Mount the test fixture in one of the three axes to the vibration table
• Attach the vibration monitoring equipment to the plug-in unit per 6.2.6
• Perform a resonance survey in accordance with 5.2
• Plot all accelerometer data in the format of acceleration versus frequency and record resonant frequency(s)
• Verify the plug-in unit structural/mechanical condition
• Verify all securing mounting parts torque and re-torque as necessary
• Perform a seismic simulation in accordance with 5.5 and 5.6
• Plot all accelerometer’s shock response spectra and the time history of the control accelerometer
• Inspect the plug-in unit and record any structural/mechanical or functional non- conformance
• Verify all securing mounting parts torque and re-torque as necessary
• Repeat the above sequence in the two remaining mutual perpendicular axes.
Plug-in unit electrical parts test (free and fixed connector)
This standard only deals with mechanical reliability under a seismic test condition The associated electrical seismic plug-in unit free and fixed connector contact tests such as LLCR
Low Level Contact Resistance (LLCR) is optional and can be determined through agreement between the supplier and the user, or mandated by specific application requirements Users must specify the parameters for measurement equipment, which should include at least the measurement system's current, voltage, resistance, and the duration for the maximum length of intermittent or high resistance values.
Acceptance criteria
The plug-in unit and its interface with the test chassis or subrack show no permanent deformation, ensuring the integrity of components like the plug-in unit retention, ESD interface, EMC interface, guide rail, and hot swap switch function Additionally, there is no visible damage, such as abrasion, to the fixed and free connectors Furthermore, the earth bond continuity remains intact at less than 0.1 Ω, in compliance with IEC 61587-1 standards.
Category B – Chassis or subracks
General
Subracks, as defined by IEC 60297 and IEC 60917, can either be components of a cabinet or integral parts of a chassis that is itself part of a cabinet, as illustrated in Figure 10.
IEC 60297 and IEC 60917 series Chassis which do not contain a subrack are also a part of a cabinet according to the IEC 60297 or IEC 60917 series
The chassis or subrack undergoing testing must be installed in a pre-qualified cabinet that complies with IEC 61587-2 standards This standard specifies the cabinet position necessary for conducting a generic seismic test on a single chassis or subrack Additionally, the mounting conditions for the chassis or subrack are determined based on its intended use.
The mass of the chassis or subrack, along with its attachment points to the cabinet and the necessary additional support types—such as support rails, telescopic slides, and rear attachments—are crucial for the application It is essential to ensure that the attachment points of the chassis or subrack to the cabinet are secured to the recommended torque values.
• For the purpose of creating an ecosystem 3 mm aluminium front panels in accordance with
For optimal compatibility and standardized test reports across various supplier solutions, the assembly of IEC 60297 or IEC 60917 should be utilized at the unused front and rear mounting positions of the cabinet While front panels with thicknesses other than 3 mm and different materials are allowed, this must be agreed upon with the user It is essential to ensure that the attachment points of the front panel to the cabinet are secured to the specified torque values.
• Chassis with integrated subracks and subracks shall be assembled with simulated load plug-in units complying with Clause 4, Category A1 to A4 and 6.2.1
• Chassis with integrated subracks and subracks shall be assembled with simulated loads complying with Clause 4, Category B1 to B3
• Chassis (without integrated subracks) shall be assembled with simulated loads complying with Clause 4, Category B1 to B3
Plug-in unit 3 Front panel 1
Cabinet pre-qualified per IEC 61587-2 x z y
1 Front panels according to the IEC 60297 or IEC 60917 series are to be assembled to the front/rear of the cabinet
3 Plug-in unit load boards see 6.2.1
Figure 10 – Chassis or subrack test setup
Chassis or subrack simulated load
Subracks must be designed to accommodate the specified mass, which should be evenly distributed through the designated plug-in unit categories (refer to Clause 4, Categories A1 to A4), including the free connector as outlined in section 6.2.1 The fixed connector intended for use within the subrack must be properly attached according to its specifications Additionally, chassis should also support the mass in alignment with their intended use For chassis that incorporate an integrated subrack, they must effectively combine the requirements of both subracks and chassis.
Chassis or subrack test setup onto the vibration table
Mounting condition is referred to in IEC 60068-2-6, in which there is a reference to
The chassis or subrack test cabinet is to be attached to the vibration table in compliance with
Chassis or subrack mechanical parts under test
• Overall mechanical construction of the chassis or subrack
• Guidance feature (guide rail) of the subrack
• Plug-in unit retention device in the subrack
• EMC contact mechanical reliability See IEC 61587-3
• Earth bond continuity See IEC 61587-1.
Vibration response monitoring
• The control accelerometer shall be mounted near one of the specimen mounting bolts
A tri-axial response accelerometer will be installed on the specimen, specifically positioned at the exterior point anticipated to experience the highest levels of acceleration.
Motor actuator and Vibration table
Plug-in unit load boards
Chassis or subrack under test
Chassis or subrack under test
Cabinet pre-qualified per IEC 61587-2 see Figure 8
Figure 11 – Block diagram of the chassis or subrack test setup
Chassis or subrack measurements
The following measurements must be taken and reported: a) the critical frequency and damping ratio of the loaded chassis or subrack, assessed through sinusoidal or random waveform sweeps before and after the seismic test; b) the acceleration of the vibration table during the test; and c) the acceleration of the chassis or subrack.
Test sequence
• Mount the chassis or subrack in one of the three axes to the cabinet on the vibration table
• Attach the vibration monitoring equipment to the chassis or subrack per 6.3.4
• Perform resonance survey in accordance with 5.2
• Plot all accelerometer data in format of acceleration versus frequency and record resonant frequency(s)
• Verify the chassis or subrack structural/mechanical condition
• Verify all securing mounting parts torque and re-torque as necessary
• Perform a seismic simulation in accordance with 5.5 and 5.6
• Plot all accelerometer’s shock response spectra and the time history of the control accelerometer
• Inspect the chassis or subrack and record any structural/mechanical or functional non- conformance
• Verify all securing mounting parts torque and re-torque as necessary
• Repeat the above sequence in the two remaining mutual perpendicular axes.
Acceptance criteria
The chassis and subrack structure, along with their interfaces to the plug-in unit under test, show no permanent deformation, ensuring the integrity of components like the plug-in unit retention, ESD interface, EMC interface, and guide rail Additionally, the test cabinet interface and retention remain undamaged, with no visible wear on the fixed and free connectors Furthermore, the earth bond continuity is maintained at less than 0.1 Ω, in compliance with IEC 61587-1 standards.
Example of test setup reporting
Subrack test setup reporting
The cabinet has been pre-qualified according to IEC 61587-2 standards, and it meets test category B as specified in IEC 61587-5 It falls under subrack mass category B2, also per IEC 61587-5 The plug-in unit load consists of 12 units, each rated at 7HP and weighing 5 kg, with the subrack aperture theoretically divided into 84 horizontal pitches (1 HP = 5.08 mm) For detailed load distribution of the plug-in unit, refer to Figure 6 in accordance with IEC 61587-5.
Plug-in unit test setup reporting
The article discusses a resonance-free (rigid) test fixture compliant with IEC 61587-5 standards It highlights a subrack that has been pre-qualified under IEC 61587-5 category B2 Additionally, it mentions a plug-in unit that falls under mass category A3, with a width of 6HP and a weight of 4 kg, indicating that the subrack's aperture is theoretically subdivided.
84 horizontal pitches, 1 HP=5,08 mm) e) Plug-in unit intended use load distribution per IEC 61587-5, see Figure 5 f) Filler panels 13 × 6HP
ATIS-0600329:2008: Network Equipment – Earthquake Resistance
GR-63-CORE: Network Equipment-Building System (NEBS) Requirements: Physical
NOTE Vibration generators and waveform contact:
• For the synthesized waveform shown in Figure 2 (single axis seismic acceleration test), contact: Telcordia
• For the synthesized waveform shown in Figure 4 (tri-axial seismic acceleration test), contact: NTT Facilities,
5 Forme d'onde d'essai et condition d'accélération 33
6 Configuration de l'essai et parties à surveiller 37
6.2.2 Charge simulée de l'unité enfichable 38
The testing configuration for the plug-in unit is outlined, detailing the setup of the testing device on the vibration table Additionally, the mechanical components of the plug-in unit under test are described, ensuring a comprehensive understanding of the testing process.
6.2.6 Surveillance de la réponse de vibration 42
6.2.9 Essai des parties électriques de l'unité enfichable (fiche et embase) 43 6.2.10 Critères d'acceptation 43
6.3.2 Charge simulée du châssis ou du bac 44
6.3.3 Configuration d'essai du châssis ou du bac sur la table de vibration 45 6.3.4 Parties méchaniques du châssis ou bac soumis à essai 45
6.3.5 Surveillance de la réponse de vibration 45
6.3.6 Mesures du châssis ou du bac 46
Annexe A (informative) Exemple de rapport de la configuration d’essai 48
A.1 Rapport de la configuration d'essai du bac 48
A.2 Rapport de la configuration d'essai de l'unité enfichable 48
Figure 1 – Spectre de réponse pour l'onde d'essai (accélération à axe unique) (taux d'amortissement de 2,0 %) 34
Figure 2 – Accélérogramme de l'onde d'essai (accélération à axe unique) 34
Figure 3 – Spectre de réponse pour l'onde d'essai (accélération sur trois axes) (taux d'amortissement de 3 %) 35
Figure 4 – Accélérogramme de l'onde d'essai pour chaque axe (accélération sur trois axes) 36
Figure 5 – Distribution de charge de l'utilisation prévue de l'unité enfichable A (discret) 38
Figure 6 – Distribution de charge de l'utilisation prévue de l'unité enfichable B
Figure 7 – Configuration dessai de l'unité enfichable – Bac 40
Figure 8 – Configuration d'essai de l'unité enfichable – Châssis avec bac intégré 41
Figure 9 – Schéma de principe de la configuration d'essai de l'unité enfichable 42
Figure 10 – Configuration d'essai du châssis ou du bac 44
Figure 11 – Schéma de principe de configuration d'essai du châssis ou du bac 46
STRUCTURES MÉCANIQUES POUR ÉQUIPEMENT ÉLECTRONIQUE –
ESSAIS POUR LA CEI 60917 ET LA CEI 60297 – Partie 5: Essais sismiques pour châssis, bacs et unités enfichables
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La Norme internationale CEI 61587-5 a été établie par le sous-comité 48D: Structures mécaniques pour équipement électronique, du Comité d'études 48 de la CEI: Composants électromécaniques et structures mécaniques pour équipements électroniques
Le texte de cette norme est issu des documents suivants:
Le rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant abouti à l'approbation de cette norme
Cette publication a été rédigée selon les Directives ISO/CEI, Partie 2
Une liste de toutes les parties de la série CEI 61587, présentées sous le titre général
Structures mécaniques pour équipement électronique – Essais pour la CEI 60917 et la
CEI 60297, peut être consultée sur le site web de la CEI
The committee has determined that the content of this publication will remain unchanged until the stability date specified on the IEC website at "http://webstore.iec.ch" regarding the relevant publication data On that date, the publication will be updated.
• remplacée par une édition révisée, ou
IMPORTANT – The "colour inside" logo on the cover of this publication indicates that it contains colors deemed essential for a better understanding of its content Users are therefore encouraged to print this publication using a color printer.
This standard is based on IEC 61587-2, which pertains to mechanical structures for electronic equipment, specifically focusing on seismic testing for racks and cabinets as outlined in IEC 60917 and IEC 60297 It also references ATIS-0600329:2008, which addresses earthquake resistance for network equipment.
This standard outlines the testing configurations, performance requirements, and acceptance criteria necessary to assess the robustness of chassis, enclosures, and associated plug-in units, in accordance with IEC 60297 and IEC 60917 It aims to ensure durability and protect functionality during and after seismic events, such as earthquakes Importantly, this standard does not replace regional seismic systems, installation standards, or specifications.
The objective of this standard is to establish a common methodology for the execution and reporting of seismic compliance testing for racks, enclosures, and plug-in units, in accordance with IEC 60297 and IEC 60917 for a specified weight category The mass distribution is determined based on the intended use The terms "intended use" or
"simulation de condition de service" ou "configuration simulée la plus défavorable" sont largement utilisés dans l'industrie des télécoms
Seismic ground motion occurs simultaneously and randomly in all directions Testing can be conducted on a single axis or three axes to simulate the seismic environment of the test.
STRUCTURES MÉCANIQUES POUR ÉQUIPEMENT ÉLECTRONIQUE –
ESSAIS POUR LA CEI 60917 ET LA CEI 60297 – Partie 5: Essais sismiques pour châssis, bacs et unités enfichables
La présente partie de la CEI 61587 spécifie les exigences d'essai sismique pour les châssis, les bacs et les unités enfichables tels que définis dans les séries CEI 60297 et CEI 60917