China
Africa
Explore chapters and articles related to this topic
Electrical Installation Methocs, Procecures And Recuirements
Published in Peter Roberts, Electrical Installation Work, 2017
All electrical circuits are also given what is termed additional protection, whereby within the consumer unit at least two residual current devices (RCDs) must be fitted. Within domestic properties, RCD’s are normally rated at 30 mA and is a device which will operate very quickly by sensing that an electrical current is not being returned through the neutral conductor and being fed down the earthing system. It will also trip under electric shock conditions because it senses that the circuit current is travelling through the person. An RCD, such as that shown in Figure 4.16, is designed to protect people.
SANITARY FITMENTS AND APPLIANCES: DISCHARGE AND WASTE SYSTEMS
Published in Fred Hall, Roger Greeno, Building Services Handbook, 2011
consumer unit and added protection provided with an in-line residual current device (RCD) trip switch. All this, of course, is dependent on there being a spare way in the consumer unit. If there is not, there will be additional expenditure in providing a new consumer unit or a supplementary fuse box. A double pole cord operated pull switch is located in the shower room to isolate supply.
Electrical Supply and Installations
Published in Fred Hall, Roger Greeno, Building Services Handbook, 2017
Most used in rural areas where the supply is overhead. An earth terminal and electrode is provided on site by the consumer. As an extra safety feature, a residual current device (RCD), generally known as a trip switch, is located between the meter and consumer unit. The RCD in this situation should be of the time-delayed type – see page 549.
Retrofitting suspended timber ground-floors; comparing aggregated and disaggregated evaluation methods
Published in Building Research & Information, 2020
David Glew, David Johnston, Dominic Miles-Shenton, Felix Thomas
For the pre-retrofit test, an Energy Conservatory Duct Blaster and a DG700 pressure/flow gauge were used to measure the airtightness of the case study dwelling. However, due to the poor air tightness of the dwelling it was only possible to achieve a maximum pressure difference of 40 Pa using this equipment. Given this, an alternative blower door, an Energy Conservatory Model 3 Blower Door with a DG700 pressure/flow gauge, was used for the post-retrofit test. However, both are calculated to a 50 Pa pressure differential the only difference being the size of the fan and the flow rates that can be achieved with the fan. The pressure and flow gauge and door fabric are identical and the same number of pressure and flow measurements were undertaken during both tests, under both pressurization and depressurization. The only difference between the tests is the range of pressures under which the tests were undertaken. By only undertaking the pre-retrofit pressurization tests with a maximum pressure differential of 40 Pa, as opposed to greater than 50 Pa, this should have minimal impact on the test results and any potential difference would be less than the level of uncertainty associated with the test method. The reason for undertaking the pre retrofits at lower pressure was because at higher pressures the increased inductive load required for the fan was enough to trip the circuit breaker on the domestic consumer unit.