Checklist for Electrical Distribution Architecture Design


I listed and explained the Tasks required for application of Electrical Distribution architecture design process in the following previous topics: 




This Checklist is exclusive for our blog, you will not find it anywhere in the web, when you use it , it will make your design more professional, more applicable and give more Credibility in front of the client.

This checklist is a summary for all the previous tenth topics and By using this Checklist, you will be able to list all the characteristics, factors and conditions that affect the design of the power architecture design (single line diagram) for any project.

What you need to do is putting ( ) in the check box in front of the right choice , the previous topics listed above will help you for determining the right choice and you can review them for this purpose.

A solved example in the next topic will show how using this Checklist to design and draw an optimal single line diagram for the project under study. Please, review this check list very well and inform me if there is any question.

Here is the check list,





Checklist For Application Of Electrical Distribution Architecture Design Process
(Put Brief Description About The Installation/Building)
First: Assigning Of Electrical Installation Characteristics
#
Characteristic
Choice
1
Activity

Industrial Buildings 

Commercial Buildings 

Residential Buildings 

Agricultural Buildings 

Educational Buildings 

Transportation Buildings 

Religious Buildings 

Parking And Storage 

Military Buildings 

Governmental Buildings 

Cultural Buildings 

Other Buildings
2
Site Topology

Single Storey Building,(Low Rise)

Multi-Storey Building, ,(Low Rise)

Multi-Building Site,

High-Rise Building
3
Layout Latitude

Low (≤ 2,000 m2)

Medium (2,000 m2- 2,500 m2)

High (> 2,500 m2)
4
Service Reliability

Minimum

Standard

Enhanced
5
Maintainability

Minimum

Standard

Enhanced
6
Installation Flexibility

No Flexibility

Flexibility Of Design

Implementation Flexibility

Operating Flexibility
7
Power  Demand

< 630 kVA

630 – 1250 kVA

1250 -  2500 kVA

> 2500 kVA
8
Load Distribution

Uniform Distribution

Intermediate Distribution

Localized Loads
9
Power Interruption Sensitivity

“Sheddable” Circuit

Long Interruption Acceptable

Short Interruption Acceptable

No Interruption Acceptable.
10
Disturbance  Sensitivity

Low Sensitivity

Medium Sensitivity

High Sensitivity
11
Disturbance Capability  Of Circuits

Non Disturbing

Moderate Or Occasional Disturbance

Very Disturbing
12
Other Considerations Or Constraints

Environment

Specific Rules

Rule Of The Energy Distributor

Attachment Loads

Load Power Supply Constraints
Second: Assigning Of Technological Characteristics
1
Environment And Atmosphere

Standard (IP,IK,C°)

Enhanced (IP,IK,C°)

Specific (IP,IK,C°)
2
Service Index

111

211

223

232

233

332

333
3
Other Considerations

Designer Experience

Utilities Requirements

Specific Technical Criteria
Third: Using Architecture Assessment Criteria
1
On-Site Work Time

Secondary

Special

Critical
2
Environmental  Impact

Non significant

Minimal

Proactive
3
Preventive Maintenance Level

Standard

Enhanced

Specific
4
Availability Of Electrical Power Supply

Availability Level (%) = (1 - MTTR/ MTBF) x 100
Forth: Step (1): Choice Of Distribution Architecture Fundamentals
1
Connection To The Upstream Network

LV Service

MV Single Line Service

MV Single Line- One Substation - One Ring Main Unit Service

MV Double Line - One Substation - Double Ring Main Unit - One Loop Service

MV Duplicate Supply Service,

MV Duplicate Supply Service With Double Busbar.
2
MV Circuit Configuration

Single Feeder, One Or Several Transformers

Open Ring, One MV Incomer

Open Ring, 2 MV Incomers
3
Number And Distribution Of MV/LV Transformation Substations

 1 Substation With N Transformers (If Power < 2500KVA)

N Substations With N Transformers (Identical Substations) (If Power >2500KVA)

N Substations With M Transformers (Different Powers) (If Power >2500KVA) (For Several Buildings)
4
Number Of MV/LV Transformers

 The Number Of Transformers (> 1) (If Power > 1250 KVA) (Area > 5000m2)

The Number Of Transformers (= 1) (If Power < 1250 KVA)
5
MV Back-Up Generator

Yes (Site Activity - Total Power Of The Installed Loads - Sensitivity Of Circuits To Power Interruptions -Availability Of The Public Distribution Network)

No
Fifth: Step (2): Choice Of Architecture Details
1
Layout

Place power sources as close as possible to the barycenter of power consumers,

Reduce atmospheric constraints: building dedicated premises

Placing heavy equipment (transformers, generators, etc) close to walls or main exists for ease of maintenance,
2
Centralized Or Distributed Layout

Centralized Layout

Decentralized Layout
3
Presence Of Back-Up Generators

Yes (Sensitivity of loads to power interruption, Availability of the public distribution network)

No
4
Presence Of An Uninterruptible Power Supply (UPS)

Yes (Sensitivity of loads to power interruptions, Sensitivity of loads to disturbances)

No
5
Configuration Of LV Circuits

Radial single feeder configuration

Two-pole configuration

Variant: two-pole with two ½ MLVS

Shedable switchboard (simple disconnectable attachment)

Interconnected switchboards

Ring configuration

Double-ended power supply

Configuration combinations
Sixth: Step (3): Choice Of MV/LV Equipment (Atmosphere, Environment, IP, IK - Service Index - Offer Availability Per Country - Utilities Requirements )
Seventh: Recommendations For Architecture Optimization
1- Use of proven solutions and equipment that has been validated and tested by manufacturers (“functional” switchboard or “manufacturer” switchboard according to the application criticality)
2- Prefer the implementation of equipment for which there is a reliable distribution network and for which it is possible to have local support (supplier well established)
3- Prefer the use of factory-built equipment (MV/LV substation, busbar trunking) allowing the volume of operations on site to be limited
4- Limit the variety of equipment implemented (e.g. the power of   transformers)
5- Avoid mixing equipment from different manufacturers.
6- Appropriate metering and analysis of loads actual consumption
7- Power factor correction solutions
8- Appropriate organisation and design of site and use of busbar truncking instead of cables wherever accurate
9- Reducing the length of LV circuits in the installation by Placing MV/LV substations as close as possible to the barycenter of all of the LV loads to be supplied
10- Clustering LV circuits wherever possible to take advantage of the factor of simultaneity ks  by:
a- Setting up sub-distribution switchboards as close as possible to the barycenter of the groups of loads if they are localized
b- Setting up busbar trunking systems as close as possible to the barycenter of the groups of loads if they are distributed.
11- Focus maintenance work on critical circuits,
12- Standardize the choice of equipment,
13- Use equipment designed for severe atmospheres (requires less maintenance).
14- Reduce the number of feeders per switchboard, in order to limit the effects of a possible failure of a switchboard
15- Distributing circuits according to availability requirements
16- Using equipment that is in line with requirements (SI index)
17- Follow the selection guides proposed for steps 1 & 2
18- Change from a radial single feeder configuration to a two-pole configuration,
19- Change from a two-pole configuration to a double-ended configuration,
20- Change from a double-ended configuration to a uninterruptible configuration with a UPS unit and a Static Transfer Switch
21- Increase the level of maintenance (reducing the MTTR, increasing the MTBF)


Download your copy Here.

In the next topic, I will explain an example for using Electrical Distribution Architecture Design Process Checklist. So, please keep following.



2 comments:

  1. I cant believe ALL of this fantastic information is FREE.... Thank You, Thank you, Thank you .....

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  2. Amazing stuff! Like so many others, my company is cutting back on expenses and training has taken a big hit. I am in charge of a team of junior designers and using this site will enable them to be more self sufficient whilst leaving me to do more of the boring management stuff that I'm paid to do. Thank you to all of the contributors for helping knowledge to grow by sharing their skills.

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