Betacom Earthing’s portable earthing devices (PEDs) are tested to establish the maximum current they can carry for a specific duration.
High temperatures from the current can soften and melt the cable strands and insulation.
The initial inrush fault current can cause strong magnetic fields which create significant mechanical forces on the clamps and their joints to cables.
A common rating example is 25,000 amps for 0.5 seconds or 1 second. This means the device can safely conduct 25,000 amps of current for half a second or 1 second without failing.
The energy capability of a PED is I2t, which is known as the Joule integral.
To convert a 0.5 second rating to a 1-second rating, you divide the current rating for 0.5 seconds by 1.414. For instance, a device rated at 10,000 amps for 0.5 seconds would be thermally equivalent to 7,100 amps for 1 second.
High current testing ensures that the PED can handle the electrical load and protect workers in case of accidental energization.
All our devices have been independently tested, and their certified current and time ratings will be quoted in their specifications.
We supply the following nominal cable sizes:
Current capacities are estimated for Copper (25mm2, 35mm2, 0.5s) and Aluminium (147mm2, 0.5s).
