In the edition, F did allow heat shrink for strain relief if approved by the shrink and ferrule manufacturer. The conductor size for each grade of ferrule also corresponds to the minimum single cable size specified for the clamp of the equivalent grade rating. This is a very good addition during a shut down on a medium-voltage power system, as shown below in Figures 8 and 9. The narrow part of the sleeve is the cable connector that is crimped onto the conductor strands. The steel links, along with their high interlink impedance, make this grounding method extremely dangerous. Work Item s - proposed revisions of this standard. 
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Shrouded ferrules have a two-part compression sleeve at one end of the ferrule. Guest Monday, 30 September The ferrules shall be tested for electrical short-circuit capacity and continuous f8555 rating.
Table 1 represents the clamp and assembly ratings that existed prior to this revision. Use the grounding clamp that is designed to fit the type of bus or connection you're connecting to.
Applying Personal Protective Grounds -- Occupational Health & Safety
The value to safety professionals is that the standard clearly identifies what clamps do, how they are rated, astj which ferrule and cable they are to be mated with. The principal difference in each type is the temperature rating of the insulation and stranding of the conductor.
Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard. These initial fault current levels are the basis for the differences in the 6-,and cycle ratings of the grounding system components. Most substation and transmission systems in the U.
This abstract is a brief summary of the referenced standard. Drilled terminal connections have no internal threads.
Train the Trainer 101: ASTM F855 Grounding Equipment Specs Made Simple
Don't step on them or reposition them using bare hands. Test the voltage detector on a known live circuit, test all circuits that should be de-energized, then retest the voltage detector on a known live circuit.
TPG testing is done on complete assemblies. National equipment standards constantly evolve due to near misses and incidents that occur in the field. Historical Version s - view previous versions of standard.
The values in parentheses are the inch-pound units. Shrouded-type ferrules are designed to be used with ASTM-type grounding cable. To meet ASTM standards, temporary personal protective grounds must use multistranded flexible cable conductor installed in a rated clamp using protective cable ferrules.
Failures of assemblies can include cables fusing, cable pulling out of ferrules, ferrules breaking or melting, and clamps breaking at different locations. This DC offset asymmetry creates the initial high current in the first cycles of a short circuit.
Resistance in the protective ground increases current across the worker in a fault. As an example, don't try to use a clamp designed for tubular bus on a flat bus. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
The slight design difference of this clamp addresses pressure applied to the conductor, eye screw torque, current flow direction, current transfer area contact, material type and jaw style, which results in superior performance.
Ferrules are rated Grade 1 to Grade 7 in withstand, ultimate and continuous current just as clamp grades 1 to 7, making electrical ratings easy to match. Calculating Fault Current Calculation of fault current is best accomplished through the services of an engineer experienced in utility systems. If the system has a nominal voltage above V, grounding is a mandatory requirement. That is where preambles to the standards, interpretations, CPLs and consensus standards are needed. A maintenance program is a must to ensure the integrity of the assembly remains intact.
The assembly creates a short circuit, causing the circuit to relay out, and protects a worker from dangerous differences in voltage while they are working.
In the past, many utilities and manufacturers used a test fixture comprised of aluminum multiconductor suspended between insulator supports. Type I has a hot-stick eye and Type II comes fitted with a hot stick. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.
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