Bump Test
IEC 60068 Standard
IEC 60068 is one of the standard series on environmental testing issued by the International Electrotechnical Commission. The IEC 60068 standard series provides a series of environmental test methods for electronic and electrical products to evaluate their performance and reliability under various environmental conditions. The IEC 60068 standard series consists of multiple parts, each part covering different environmental test methods and parameters. The main topic of this section is bump testing.
01 IEC 60068-2-29
This test is applicable to components, equipments and other electrotechnical products, hereinafter referred to as“specimens”, which, during transportation or in use, may be subjected to repetitive shocks. The bump test may also be used as a means of establishing the satisfactory design of a specimen in so far as its structural integrity is concerned and as a means of quality control. It consists basically of subjecting, on a bump tester, a specimen to repetitive shocks of a standard pulse shape with specified peak acceleration and duration.
The purpose of the test is to provide a standard procedure for determining the ability of a specimen to withstand specified severities of bump.
Acceleration and duration of the pulse
Peak acceleration (g) | Corresponding duration of the nominal pulse (ms) | Corresponding velocity change (m/s) |
10 | 16 | 1 |
15 | 6 | 0.6 |
25 | 6 | 0.9 |
40 | 6 | 1.5 |
100 | 2 | 1.2 |
Number of bumps in each direction
100±5
1000±10
4000±10
Examples of severities typically employed for various applications
Severity | Component use | Equipment use | ||
Peak acc. (g) | Duration (ms) | No. of bumps in each specified direction | ||
10 | 16 | 1000 | Transportation of fragile items by road, excluding Cross-country | General robustness test and for items installed or transported in a secured position in wheeled vehicles with no Cross-country requirement |
15 | 6 | 4000 | Minimal robustness test and for items of general application with main mechanical load occurring during transportation | Items installed in control equipment of stationary or heavy mobile machinery, for example in the vicinity of power plants |
25 | 6 | 1000 | Items installed or transported in a secured position in full cross-country vehicles Items installed in mechanical handling equipment, for example, dock cranes, fork-lift trucks | |
40 | 6 | 1000 | Transportation of items intended for use in equipment of a non-portable nature | Items which may be carried loose in wheeled vehicles (road or rail) for occasional journeys, for example, delivery |
40 | 6 | 4000 | Items for use in transportable equipment | Transportable items which are repeatedly carried loose in any type of vehicle, rail, road or Cross-country |
100 | 2 | 4000 | Lamps and spring contacts, for example for keys, telephones or switchboards |
02 KRD20 Pneumatic Bump Test Machine
KRD20 series pneumatic bump test machine replaces the traditional mechanical cam-type crash bench and is suitable for repeated impacts on electronic components, equipment and other electrical and electronic products during transportation or working.
Features:
l Fully pneumatic driven, clean and environmentally friendly, good repeatability and high reliability.
l Control the frequency of bumps by adjusting the gas pressure to achieve continuous high-frequency bumps.
l Test time and bump frequency can be set arbitrarily, and it will stop automatically after the test is completed
Half-sine pulse waveform tolerance band
In the figure:
Tolerance range line
------Nominal pulse line
D ───Nominal pulse duration, ms
A ───The peak acceleration of the nominal pulse, m/s2
T ───Minimum monitoring pulse time
Velocity variation tolerance:
The tolerance of the bump pulse velocity change should be within ±15% of the nominal value. The bump pulse velocity change should be integrated from 0.4D before the pulse to 0.1D after the pulse. As shown in Figure
Transverse movement:
At the detection point, the peak acceleration perpendicular to the bump direction is not more than 30% of the nominal pulse peak acceleration.
The transverse movement ratio is calculated as follows:
In the formula:Ax、Ay——Two transverse peak accelerations perpendicular to the main bump direction and perpendicular to each other in the same measurement (m/s2).
Az——Pulse value acceleration in the main bump direction (m/s2).