Controlgear assemblies

Low voltage switchgear and controlgear assemblies. Type tested and partially type tested assemblies 8623 (Part-1) 1993 BS EN 60439 1/1994... 

General guidelines during installation and maintenance of a switchgear or a controlgear assembly 13/384... 

Appendix Painting procedure of switchgear and controlgear assemblies and treatment of effluent A13.1 Introduction 13/400... 

Depending upon their application, a switchgear or a controlgear assembly can be one of the following types ... 

A switchgear or a controlgear assembly will be designed to fulfil the following design parameters ... 

Switchgear and controlgear assemblies 13/345 Table 13.3 Standard insulation (impulse) levels for range II voltage systems (V , > 245 kV)... 

Switchgear and controlgear assemblies 13/353 Table 13.8 Typical parameters of a power generating station and Its likely fault levels... 

Switchgear and controlgear assemblies 13/355 Table 13.9 Fault currents (r.m.s.) in a generator circuit under different fault conditions... 

In outdoor type switchgear or controlgear assemblies the normal practice is to provide a double door in the front to house the front panel and protect the door knobs, meters, lights, pushbuttons, reset knobs or other accessories mounted on the door and thus prevent water or dust leaking through joints, knockouts and fitments etc. It is also recommended to have a canopy on the top of the enclosure to protect the panel from direct rain. Figures 13.6 and 13.28 illustrate this type of construction. 

Installations prone to heavy vibrations and shocks stich as on the mounting platform near a laige power-generating unit, on a ship, locomotive and similar installations may require provisions to absorb shocks and dampen vibrations to prevent loosening of components and wire connections in a switchgear or a controlgear assembly. Some economical methods to achieve this can be by providing ... 

Below we discuss briefly the constructional requirements and general manufacturing practices for cubicle-type switchgear and controlgear assemblies, and the electrical and the mechanical design considerations to comply with the above design parameters and service conditions. 

The above are the more obvious constructional, design and safety features for a switchgear or a controlgear assembly. For more details and additional requirements refer to lEC 60439-1 for LT, lEC 60298 and lEC 60694 for FIT and ANSI-C-37/20C, common for LT and FIT switchgear and controlgear assemblies. 

One may follow field tests as discussed in Section 14.5 before putting the switchgear or the controlgear assembly into service. 

If the insulation resistance is observed to be low the interior of the switchgear or the controlgear assembly should be dried out to attain the required value before energizing it. The procedure to dry the moisture is similar to that for motors and is discussed in Section 9.5.2. In this case during the heating-up period the insulation resistance may first drop and reach its minimum, stabilize at that level and then start to rise gradually. Continue the process until it reaches its required level as shown in Table 14.7. 

Particular requirements for low-voltage switchgear and controlgear assemblies intended to be installed in places where unskilled persons have access to their use. Distribution boards 8623-3/1993 BSEN 604.39-3/1991 ... 

Painting of all metallic surfaces of a switchgear or a controlgear assembly is an essential requirement to provide it with an aesthetic appearance, on the one hand, and to prevent it from rust and corrosion, on the other. Painting serves these purposes by providing the machine with a hard and longer-lasting metallic surface. We describe briefly, the basic procedure to paint and test painted surfaces. In the discussion, we have laid more emphasis on MS sheet-metal surfaces as these are more typical. 

Switchgear and controlgear assemblies 13/403 Table A13.3 Pickling and de-rusting process in mildly scaled and mildly rusted surfaces... 

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