IEEE Std C37.90.3:2001 pdf free download

IEEE Std C37.90.3:2001 pdf free download.IEEE Standard Electrostatic Discharge Tests for Protective Relays.
The discharge generator shall be grounded directly to the ground reference plane. close to the EUT. using a ground cable 2rn long with a width of at least 20mm. A ground cable longer than 2m may be used when required to reach test points on large equipment. Also, the test supplies and monitoring equipment shall be grounded to the ground reference plane. During the test, the grounding cable of the discharge generator shall be kept at least 0.1 m from the EUT. and at least 0.2 m from metal surfaces other than the ground reference plane. Cables interconnecting the FLiT, test supplies, and monitoring equipment shall be kept at least 0.1 m from the ground plane.
For small equipment, a horizontal coupling plane (HCP) shall be used between the table and the EUT. Insulation with thickness of 0.5 mm or smaller shall be placed between the HCP and the EUT. A vertical coupling plane (VCP) may be needed for both floor-mounted equipment and table-mounted equipment (see Figure I).
The HCP and VCP are to be constructed from the same material and thickness as the ground reference plane. The HCP shall be a minimum of I.6m by 0.m and project beyond the EUT by at least 0.1 m on each side. The VCP shall be 0.5 m by 0.5 m and located 0.1 m from the vertical face of the EUT. Each coupling plane shall be grounded through resistors as shown in Figure 3 and Figure 4. The I M resistors RH) located at each end of the charge bleed strap must have a transient withstand voltage of 10kv or greater to prevent breakdown which would cause false current loops. The 2k?rcsistor(RL) located between the two RH resistors prevents the stray capacitance of the high-voltage resistor from forming a ringing circuit.
3.2.5 Test point selection
The points selected for the application of the test shall be those that arc accessible under normal in- service conditions. Test points shall include relay case, knobs, push buttons, switches, terminals, data ports. keypads, target resets. cLc.
The application of discharge to any point of (he equipment that is accessed only for repair and maintenance purposes is outside the scope of this standard. Examples are
a) Terminals normally wired at installation.
b) Setting adjustments that are not accessed during normal service conditions.
Categorize all test points as conductive or nonconductive and follow the testing procedure given in Figure 1. Test both horizontal and vertical coupling planes when coupling plane testing is required by Figure I. Vertical coupling plane testing shall be performed in all four positions relative to the EUT.