Posts Tagged 'relays'

We are pleased to present below all posts tagged with 'relays'. If you still can't find what you are looking for, try using the search box.

Differential protection, the good old days
Electromechanical Relays
Frame Leakage Protection
Tips for a better Low Voltage Protection Discrimination Study


How to Calculate Motor Starting Time

Request to look at induction motor starting time have come up a few times on the site. Hopefully in this post, I give you guys some idea on how to calculate...

Why is electricity so hard to understand?

It's been a busy few months on different projects or busy couple of decades depending on how I look at it. I can say that on the odd (frequent) occasion...

Lightning Risk Assessment (IEC 62305)

IEC 62305 'Protection against lightning' requires a risk assessment be carried out to determine the characteristics of any lightning protection system...

Cable Sizing Tool

Our cable sizing tool is one of the more popular tools on the site.  The tool enables cables to be sized in compliance with BS 7671 (the IEE Wiring Regulations...

Power Factor

Power factor is the ratio between the real power (P in kW) and apparent power (S in kVA) drawn by an electrical load. The reactive power (Q in kVAr)...

Large Hadron Collider

The 27 km, Euro 6 billion  Collider lies on the border between France and Switzerland, took nearly 30 years to complete.  Some of the lofty goals for the...

The ac resistance of conductors

In a previous article I looked at the dc resistance of conductors and in this article we turn our attention to ac resistance. If you have not read the...

How to Size Current Transformers

The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...

HTML Symbol Entities

HTML supports a variety of entity symbols which can be entered using either numbers or an entity name.  The number or name is preceded by the ‘&’ sign...

Software Usage Guidelines

Using software in our  work is essential for most of us and we are becoming even more dependant on it's use.  While software is a great asset, many times...

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