Grounding Audit Report | Interstates

Using an AEMC 6416 Clamp-On Ground Resistance Tester (Test Current: 1mA – 30A), the resistance to ground was measured at all accessible ground whips. A clamp-on ground resistance meter is effective in measuring the resistance at any point in the grounding system to earth but will not provide accurate readings if the meter is measuring a closed loop of the grounding system. However, for the purposes of this audit, this method was sufficient in identifying points where a grounding connection was ineffectively grounded to earth or was disconnected from the ground loop. The recommended standard target for grounding is 5.00 Ohms or less for ground resistance which is under the NEC required value and 0.50 Ohms or less for Point to Point resistance. The planview drawings in Appendix A: Planview Drawings indicate all areas where grounds were tested, and Table 1: Test Point Table indicate the ground resistance and continuity values that were measured. In regards to the magnet equipment, issues were found on site and suggestions, as well as actions, were discussed on site to remediate the bad ohm readings. The system was grounded from the steal frame with no jumper from the already solidly bonded frame to a steal handguard. A jumper was installed to properly ground the frame, the metal detector, and the surrounding chutes.

Conditions The Ambient Temperature of the areas on the days the grounding audit was conducted are as follows:

• Electric Rooms: 75° F • Outside Areas: 45° F • Bagging/ Production Area: 65° F • Warehouse: 85° F


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