# Electricity: Part 2 - Protection

Electrical safety is extremely important, and a combination of technology and procedures helps achieve adequate protection.

Fig.1 - In an earthed system, the electrical parts are inside a metallic enclosure that is grounded. Any contact between live parts and the enclosure will cause a fault current to ground that blows the fuse and cuts the power.

Fig.2 At a) the ELCB cuts the power if it senses even a small ground current from the protected wiring. It can work if a poor ground is inadequate to pass heavy ground currents under fault conditions. At b) the RCCB constantly compares the currents at two points in the circuit, which should balance. Any imbalance must be due to current leaving the circuit, which is a fault condition and trips the power.

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Every TV viewer compares live content with what they regularly see on TV, with multimillion-dollar talent with more multimillions in technical equipment and support.

# Information: Part 3 - Applying Statistics

We are not done with statistics yet. In a sense we will never be done with it and it is better to know how to deal with it than to ignore it. It is better still to know how others…

# Transforms: Part 5 - OFDM

Thus far we have looked at transforms from a somewhat abstract viewpoint. In contrast, here we look at an application where transforms take center stage.

# Electricity: Part 3 - AC Systems

Here we look at alternating current (AC) systems and how generating AC often requires an intermediate step of converting to DC to improve the efficiencies of AC generators.

# Information: Part 2 - Gaussian Distribution

Information can never be separated from its nemesis, which is uncertainty. The former is only possible by limiting the latter.