How To Choose System’s Earthing Point And What Is The Practice Throughout The World

Normally in directly earthed and effectively earthed systems every available neutral point is earthed. Deviations from this occurs when the transformers neutral points are left unearthed. This is done to... Read more
By EEE, ADBU

Differential Protection Of Feeders For Transformers And Tee-Offs (Tapped Lines)

On transformer feeders, the transformer and line or cable are connected in series and form a unit. In this manner, one CB can be saved. On feeders with tee-offs, transformers... Read more
By EEE, ADBU

How To Control Reactive Power In Larger Electrical Plants With Multiple Incomers

Most compensation banks are controlled stepwise. For this purpose it is essential to ‘know’ when it is allowed to (de)activate a capacitor step by the power factor relay (controller). The... Read more
By EEE, ADBU

Overhead vs. Underground Residential Distribution Circuits. Which One Is ‘Better’?

This debate continues. Both designs have advantages (see Table 1). The major advantage of overhead circuits is cost. An underground circuit typically costs anywhere from 1 to 2.5 times the... Read more
By EEE, ADBU

We can load distribution transformer heavily when it is cold, but when it’s hot…

Distribution transformers (commonly mineral-oil-immersed type) are output rated and their loading and sizing guidelines of many utilities are based on ANSI/IEEE C57.91. Distribution transformers can deliver their rated kVA without... Read more
By EEE, ADBU

The Practical Basics Of Synchronous Motors That Every Electrical Engineer Should Know

Like the asynchronous motor, the synchronous motor consists of a stator and a rotor separated by the air gap. It differs from the asynchronous motor in that the flux in... Read more
By EEE, ADBU

Troubleshooting Transformer In Power Substation And Detailed Failure Investigation

Failure of transformer in power substation is not a sudden phenomenon, for that matter each and every failure will take place only after alerting through some pre-signs. If they went... Read more
By EEE, ADBU

Simple Calculation of Flood Light, Facade Light, Street Light & Signage Light-(Part2)

(B) Facade Lighting:

• Normally Facade Lighting are used to illuminate Building area from Outer Side. 
• There are three factor should be consider while designing of outdoor Facade Lighting.

1. Setback
2. Spacing
3. Aiming

1) Setback:

• The recommended setback should be 3/4 times the building height. 
• If a building is 10 Meter tall, the recommended setback is 7.5 Meter from the building. 
• If the locating the floodlight closer to the building will sacrifice uniformity and If setting it further back will result in loss of efficiency.
• Setback distance = 3/4 x Building height
• Setback distance =3/4 x (10 Meter) = 7.5 Meter 

2) Spacing:

• Spacing of floodlights should not be exceeding two times the setback distance. 
• If the setback is 7.5 Meter the floodlights should not be placed more than 15 Meter apart.
• Spacing = 2 x setback distance
• Spacing=2 x 5  = 15 Meter

3) Aiming:

• The floodlight should be aimed at least 2/3 the height of the building.
• If a building is 10 Meter high, the recommended aiming point is approximately 6.6 Meter high. 
• After installation aiming can be adjusted to produce the best fine appearance. 
• Aiming Point = 2/3 x Building Height.
• Aiming Point =2/3 (10 Meter) = 6.6 Meter high

(C) Sinage Lighting:

• Normally Sinage Lighting are used to illuminate Sinage Board either Floor Mounted or Pole Mounted
• There are three factor should be consider while designing of Sinage Board Lighting.

1. Setback
2. Spacing
3. Aiming

1) Setback:

• When using floodlights to light a sinage, the setback should be 3/4 the sign height
• If the sinage height is 18 Meter then the setback distance would be 13.5 Meter. 
• If the floodlight closer to sinage will sacrifice uniformity while setting it further back will in a loss of efficiency.
• Setback distance = 3/4 x sinage height
• Setback distance =3/4 (18 Meter) = 13.5 Meter.

2) Spacing:

• The spacing floodlights should not be exceed two times the setback distance. 
• If the setback is 13.5 Meter, the floodlights should not be placed more than 27 Meter apart. 
• Spacing = 2 x setback distance.
• Spacing = 2 x 5 (Meter) = 27 Meter.

3) Aiming:

• The floodlight should be aimed at least 2/3 up the sign.
• If a sign is 18 Meter tall, then the floodlight should be aimed approximately 12 Meter high. 
• Aiming can be adjusted to produce the best appearance. 
• Mounting a full or upper visor to the floodlight can reduce unwanted glare. 
• Aiming point = 2/3 x sign height
• Aiming point =2/3 (18 Meter) = 12 Meter high

Street Light Pole Height & Spacing (as per CPWD):

• There are four type of Street Light Pole arrangement.
• One side Type.
• Staggered Type.
• Opposite Type.
• Central Type.
• As per CPWD we can calculate Pole Height and Spacing as per under

(1) One side Street Light Pole arrangement.

• Pole Height = Width of Road.
• Pole Spacing = 3 to 4 Times Height of Pole.
• If the Road width is 8 Meter than
• Pole Height=8 Meter
• Pole Spacing =24 to 32 Meter.

(2) Staggered Type Street Light Pole arrangement.

• Pole Height = 0.8 time Width of Road.
• Pole Spacing = 3 to 4 Times Height of Pole.
• If the Road width is 8 Meter than
• Pole Height=6.4 Meter
• Pole Spacing =24 to 32 Meter.

(3) Opposite side Street Light Pole arrangement.

• Pole Height = 0.5 time Width of Road.
• Pole Spacing = 3 to 4 Times Height of Pole.
• If the Road width is 8 Meter than
• Pole Height=6.4 Meter
• Pole Spacing =24 to 32 Meter.

(4) Central Street Light Pole arrangement.

• Pole Height = 0.8 time Width of Road.
• Pole Spacing = 3 to 4 Times Height of Pole.
• If the Road width is 8 Meter than
• Pole Height=4 Meter
• Pole Spacing =24 to 32 Meter.

November 02, 2017 at 08:46PM

Facebook Banned Electrical Technology Official Page #JusticeForElectricalTechnology

Facebook Deleted Electrical Technology Official Page

#JusticeForElectricalTechnology #FacebookBannedElectricalTechnology

Dear All

We are getting lots of mail from you about the new tutorials and Electrical Technology page here on Facebook.

We are very sorry to show that #Electrical Technology Official Page on Facebook (http://ift.tt/2iSCwzU) has been taken out without a specific reason, warning or even an automated response.

We have submitted an appeal, but there is no response from their side (even we didn’t get an automated reply that our case has been registered).

We have spent lots of $$ and efforts since last 6 years on the page as well as main blog to bring the free & quality content for you.

To support the campaign, Please share the hashtag (given below) around the social media networks. If they reinstated the page, We would be able to continue the free education distribution around the world.

#JusticeForElectricalTechnology

#FacebookBannedElectricalTechnology

Thanks for your patience and support.

Electrical Technology

The post Facebook Banned Electrical Technology Official Page #JusticeForElectricalTechnology appeared first on Electrical Technology.

November 02, 2017 at 05:02PM

Calculate and Draw a Single Line Diagram For The Power System (Generators, Motors, Transformers & Lines)

This technical article explains how to calculate and draw a single line diagram of the three-phase, 60-Hz system power system with generators, motors, transformers and lines. The following components comprise... Read more
By EEE, ADBU