Knowledgebase

Achieving electrostatic discharge (ESD) immunity by design

Power Regulating Methods

Download the pdf below for a chart comparing different regulating methods.

Power Quality Fact Sheets 1-10

Techniques for assessing the electromagnetic environment

How to assess the EMC environment plus guidelines and simple calculations.

Where does Electromagnetic Interference come from?

Electromagnetic interference (EMI) can manifest in a variety of ways and the emission source is usually frequency dependent. The interference can be conducted, through mains...

Electronic regulators

THYRISTOR CONTROLLERS

Thyristor regulators are used to control the energy supplied to a wide variety of loads. There are a number of circuit configurations that can be...

Harmonics

Harmonics are always present but may not be apparent - so be aware!

Power Quality Standard EN 50160

How good is our electricity supply?

Switch mode power supplies

Most computers and television sets derive their power from a switch mode source. In industry the pattern is the same with varying levels of complexity. The main driving forces...

The effects of line reactors on mains harmonics

The harmonic solution

Harmonics are a serious problem and cannot be ignored for a variety of practical and legislative reasons.

In identifying the problem, probably one of the toughest...

Column transformers

Nowadays these very large variable transformers are used mainly for test applications, where it is important to have a variable voltage with a nearly perfect sine wave. However,...

Motorised transformers

Both variable transformers and potentiometers can be motorised. Normally the reversible motor is powered from the mains supply and the setting time selected, from a few seconds...

Ohm

Everybody has heard about Ohm's Law it states that Voltage, Current and Resistance in a circuit are all related:

Voltage/Current = Resistance
or V/I = R

Potentiometer dimensions

A potentiometer is a three terminal voltage divider, often shortened to pot. The resistance change with shaft rotation may follow different laws - stepped linear, logarithmic. A...

Safety Fact Sheets 1 - 8

Essential information on electrical safety issues. Including - Selection of Fuses - Earthing and Bonding - New Cable Colours - Electic Shock Data - Residual Current Devices -...

Subscriber Letter

To subscribe to our mini guide series please enter your details into the letter and fax it back to REO (UK) LTD.

The history of power regulation

In 1837 Thomas Davenport a Vermont blacksmith built the first DC electrical rotating machine. Some time after, when Thomas Edison created the light-bulb in 1879 and subsequently...

Transformer dimensions

In a similar way to resistors, variable transformers are available in two forms, toroidal and linear (or column type).

What are the most commonly used solutions for solving power quality problems?

A summary of the different solutions used for solving power quality problems with the results of a survey from 1400 sites in 8 countries.

What causes power quality problems?

This fact sheet summarises the main EMC phenomena that cause power quality problems in an industrial environment

Electric Shock Data

Have you ever considered what is the lowest current that is capable of causing a fatality? This interesting fact sheet provides lots of useful information relating to electric...

Low Voltage Directive

A fact sheet produced by Ken Lawrence - Electrical Safety Consultant on the key points of the Low Voltage Directive (LVD).

The new EMC Directive 2004/108/EC

The new UK EMC Regulations, implementing the second EMC Directive 2004/108/EC, are now in force. Brian Jones, secretary of the European EMC standards committee CENELEC/TC210 has...

An overview of variable transformers

In a similar way to resistors, variable transformers are available in two forms, toroidal and linear (or column type).

The toroidal transformer comprises...

Braking Resistors Application Sheet

The braking resistor is connected in the DC link, between the recifier and the switching semi-conductors. When the DC voltage rises, to a preselected limit, a chopper circuit...

Electromagnetic field theory

It was the scientist Michael Faraday who first studied in detail the phenomena involving the interaction between electricity and magnetism. Amongst his many achievements, he is...

EMC Fact Sheets 1 - 7

A set of fact sheets on basic EMC issues including - Introduction - Good Practice - Installation and Cabling - EMC Filters - Electromagnetic Spectrum - Electrostatic Discharge -...

EMC Filters installation guide

This information sheet explains where to postion a filter, cable routing considerations, how to bond to earth correctly, the importance of leakage current, cooling and current...

Filter Installation Guidelines

Essential information on how and where to install an EMC Filter; bonding, earth-leakage currents; current rating and cooling.

Isolation Transformers

An explanation of the various ways in which isolation transformers provide protection against shock hazards.

BANANA SKIN REPORT OF ELECTRICAL/ELECTROMAGNETIC INTERFERENCE

New kidney dialysis machines very susceptible to power quality issues

Power quality is especially critical in hospitals, where life sustaining...

BANANA SKIN REPORT OF ELECTRICAL/ELECTROMAGNETIC INTERFERENCE

Examples of interference from NASA

NASA Reference Publication 1374 (RP-1374), “Electronic Systems Failures and Anomalies Attributed to...

BANANA SKIN REPORT OF ELECTRICAL/ELECTROMAGNETIC INTERFERENCE

Some thoughts on EMC and safety, and the security of bank accounts

Personally, I could list a ton of stuff that would instil fear and loathing...

Using UL ‘Yellow Cards’ to speed up your UL product safety approvals.

By John Showell of Product Approvals Ltd

This article gives guidance on how to use the Underwriters Laboratories (UL) 'yellow card' system to help in obtaining your...

BANANA SKIN REPORT OF ELECTRICAL/ELECTROMAGNETIC INTERFERENCE

10MW power converters interfere with wired telephones over 12 miles away

To cope with increased North Sea oil production, two new pumping stations...

BANANA SKIN REPORT OF ELECTRICAL/ELECTROMAGNETIC INTERFERENCE

Variable speed motor drive interferes with plastics moulding machine

The moulding machines concerned use high pressures and high temperatures to...