Consumer units

Waste Treatment. Microwave energy has been studied for the desulfurization of coal (qv) and treatment of wastes (190). Developments in microwave incinerators for medical and radioactive wastes have occurred (191,192). Even a consumer unit for consumption of sohd household waste has been proposed (193). Economic factors remain a key barrier in these developments. 

When a flow was started along the steam main by opening a M-in. valve leading to a consuming unit, the movement of the condensate fractured the main [6]. 

Redosing within a single episode Redosing may start 15 minutes after the previous unit has been completed (30 minutes after the start of the previous unit). Do not give more than 2 units for each individual breakthrough cancer pain episode while patients are in the titration phase and consuming units which individually may be subtherapeutic. 

Calculate the PER based on weight gained by test group in grams divided by the total amount of protein consumed (unit bi.2). Total protein is calculated based upon measurement of total nitrogen in the diet. 

Sites contaminated by POPs The Methods for the Prevention and Control of Environmental Pollution Caused by Abandoned Hazardous Chemicals promulgated and implemented in 2005 states that if hazardous chemical production, stockpiling, and consuming units want to change the line of production, stop production, close off, or dissolve, they should report the environmental restoration program to the environmental protection department above the county level. Upon obtaining the approval of the department, the contaminated sites shall be restored within a stipulated time period. 

Senior engineers shall decide in consultation with experienced plant operating personnel the order of importance of all critical water consuming units and the requirement at each of them for about half an hour. The ESR shall have a volume about 20 % more than the total of these individual requirements. Management shall invest an amount towards the cost of tank, its support structure, water piping for filling, automatically (opening) solenoid valves, etc. 

Monitoring performance of steam consuming units such as process reactors, multiple effect evaporators (measuring their steam consumption and condensate recovery)-,... 

Switchgear assemblies including consumer unit enclosures must be ... 

This new regulation has been introduced to protect against fire that can result from the overheating of connections within consumer units. Overheating may occur because connections have not been properly made or because they have become loose. 

Figure 3.28 MCBs - B Breaker, fits Wylex standard consumer unit (courtesy of Wylex).

Consumer units are now supplied which incorporate one or more RCDs, as shown in the On Site Guide Figs 3.6.3 (iv) to 3.6.3 (v). 

In a split-board consumer unit, about half of the total number of final circuits are protected by the RCD. A fault on any one final circuit will trip out all of the RCD protected circuits, which may cause inconvenience. 

Figures 3.34 to 3.36 show circuits protected by RCBOs. The use of RCBOs wiii minimize inconvenience and disruption in the event of a fauit occurring, because oniy the fauity circuit wiii be disconnected by the RCBO. However, aiternative consumer unit arrangements using MCBs and RCDs are permissibie and are shown in the On Site Guide at Section 3.6.3.

A house extension has a total load of 6 kW installed some 18m away from the mains consumer unit for lighting. A PVC insulated and sheathed twin and earth cable will provide a sub-main to this load and be clipped to the side of the ceiling joists over much of its length in a roof space which is anticipated to reach 35°C in the summer and where insulation is installed up to the top of the joists. Calculate the minimum cable size if the circuit is to be protected by a type B MCB to BS EN 60898. Assume a TN-S supply, that is, a supply having a separate neutral and protective conductor throughout. 

Extensions or alterations to existing single-phase installations do not require marking at the interface between the old and new fixed wiring colours. However, a warning notice must be fixed at the consumer unit or distribution fuse board which states ... 

Implementation - Amendment 3 published in January 2015. The changes become law on 1 July 2015. First January 2016 is the date at which Regulation 421.1.200, domestic consumer units, comes into effect. 

Consumer units - Recent fire statistics have shown that a large number of domestic fires involved plastic consumer units as a source of the fire. Consumer units are often located at the entrance or exit door or under stairs, raising the possibility that a fire starting as a result of faulty wiring could spread to coats or other household items and block the emergency escape routes. Regulation 421.1.200 now requires that consumer units be manufactured from non-combustible material, for example metal, or be enclosed in a non-combustible enclosure. Consumer units and switchgear must comply with BS EN 61439-3. 

Consumer units can now be supplied which incorporate an RCD, split boards, where half of the final circuits are RCD protected so that any equipment supplied by the consumer unit to socket outlet circuits or out of doors circuits which are outside the zone created by the protective equi-potential bonding, such as a garage or greenhouse, can have the special protection required by lEE Regulations 411.3.3 and 415.1.1. 

In this table, I am assuming a standard 230V domestic installation, having a sheathed earth or PME supply terminated in a 100 A HBC fuse at the mains position. Final circuits are fed from a consumer unit, having Type B, MCB protection and wired in PVC insulated and sheathed cables with copper conductors having a grey thermoplastic PVC outer sheath or a white... 

The testing of a ring circuit protected by a general-purpose RCD to BS EN 61008 in a split-board consumer unit is carried out as follows ... 

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