Grounding requirements

Each electric motor and connected control gear is grounded separately at least two points. The ground resistance should be checked to ensure continuity of ground conductors. Refer to Chapter 21 for more details on grounding requirements. 

Grounding requirements All components that handle flammable gases and dusts are electrically grounded to provide a safe path lor an electrostatic charge to leak away. 

The vertical cylindrical column provides, in a compact form and with the minimum of ground requirements, a large number of separate stages of vaporisation and condensation. In this chapter the basic problems of design are considered and it may be seen that not only the physical and chemical properties, but also the fluid dynamics inside the unit, determine the number of stages required and the overall layout of the unit. 

When installing conductive nonmetallic piping and metallic pipe with nonmetallic linings, consideration should be given to the need to provide electrical continuity throughout the system and to grounding requirements. This is particularly critical in areas with potentially explosive atmospheres. 

Electromagnetic and gravitational surveys on the ground require that the appropriate sensor or sensors be moved over the site following a surveyed grid, so that the sensor readings are correlated with location. Some sensors are small enough to be carried in a backpack, while others are carried on a motorized vehicle. 

Low-level input sensors such as thermocouples, turbine meters, speed transmitters and a number of process analyzers complicate system selection. Signal conditioning equipment is required for low-level inputs to both the back-up system and computer data acquisition systems. If the system is to be installed as an intrinsically safe system, multiple grounding requirements conforming to intrinsic safety grounding must be referenced to the same safety ground to avoid multiple ground problems. 

Others try to sit on the fence. Many believe in the God of the Bible, but contend that the Creation was the result of evolutionary processes. These are the proponents of theistic evolution. A later chapter takes a closer look at the theistic evolutionist s attempts to synthesize the polar opposites of the Bible and evolutionary theory, but in short this middle ground requires twice as much faith as the two other belief systems because it requires faith in both. 

Anon, An Exploratory Study to Determine the Integrated Technological Air Transportation System Ground Requirements of Liquid-Hydrogen-Fueled Subsonic, Long-Haul Civil Air Transports, NASA CR-2699 (May 1976). 

The protective grounding required by 1926.962 iimits to safe vaiues the potentiai differences between acces-sibie objects in each empioyee s work environment, ideaiiy, a protective grounding system wouid create a true equipotentiai zone in which every point is at the same eiectric potentiai. in practice, current passing through the grounding and bonding eiements creates... 

The corresponding ground productivity Pg, which is defined as the biomass produced per unit time and ground required for the installation, is related to the height of bubble column, the distance between adjacent column installations (L), and the biomass concentrations at the beginning (xq) and at the end of operation (xf) [87],... 

When designing a grounding system, consideration of developing a grounding map that identifies ah grounding requirements and voltage/current/frequency requirements... 

At 1910.106(e)(6)(ii), OSHA says only that Class I liquids shall not be dispensed into containers unless the nozzle and container are electrically interconnected. As such, flammable liquid storage cabinets do not need to be grounded under the OSHA standard. However, published materials from OSHA s Hazardous Materials course (Course 201), indicate that the requirement to ground flammable storage cabinets is found in NFPA77, Recommended Practice on Static Electricity. If NFPA77 has been adopted as by an employer s state or local fire code, then compliance with this grounding requirement would be necessary. 

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