Example: electrical installation in a printworks

Brief description

Printing of personalized mailshots intended for mail order sales.

Characteristic	Category
Activity	Mechanical
Site topology	single storey building, 10000m² (8000m² dedicated to the process, 2000m² for ancillary areas)
Layout latitude	High
Service reliability	Standard
Maintainability	Standard
Installation flexibility	No flexibility planned: - HVAC - Process utilities - Office power supply Possible flexibility: - finishing, putting in envelopes - special machines, installed at a later date - rotary machines (uncertainty at the draft design stage)
Power demand	3500kVA
Load distribution	Intermediate distribution
Power interruptions sensitivity	Sheddable circuits: - offices (apart from PC power sockets) - air conditioning, office heating - social premises - maintenance premises long interruptions acceptable: - printing machines - workshop HVAC (hygrometric control) - Finishing, envelope filling - Process utilities (compressor, recycling of cooled water) No interruptions acceptable: - servers, office PCs
Disturbance sensitivity	Average sensitivity: - motors, lighting High sensitivity: - IT No special precaution to be taken due to the connection to the EdF network (low level of disturbance)
Disturbance capability	Non disturbing
Other constraints	Building with lightning classification: lightning surge arresters installed Power supply by overhead single feeder line

Criteria	Category
Service conditions	IP: standard (no dust, no water protection) IK: standard (use of technical pits, dedicated premises) °C: standard (temperature regulation)
Required service index	211
Offer availability by country	No problem (project carried out in Europe)
Other criteria	Not applicable

Criteria	Category
On-site work time	Standard (see 5.1)
Environmental impact	Minimal: compliance with European standard regulations
Preventive maintenance costs	Standard (see 5.3)
Power supply availability	Pier 1 (see 5.4)

Choice	Main criteria	Solution
Connection to upstream network	Isolated site, 3500 kVA	MV single-line service
MV Circuits	Layout + criticality	single feeder
Number of transformers	Power > 2500kVA	2 x 2000kVA
Number and distribution of substations	Surface area and power distribution	2 possible solutions: 1 substation or 2 substations if 1 substations: Normaly open bus-coupler between MLVS if 2 substations: Main LV switchboard interconnected by a busway
MV Generator	Site activity	No

Fig. D31: Two possible single-line diagrams

Choice	Main criteria	Solution
Layout	Service conditions	Dedicated premises
LV circuit configuration	2 transformers, requested by the power demand	Solution from fig.D22 or D23 are possible
Centralized or distributed layout	Uniform loads, distributed power, scalability possibilities Non-uniform loads, direct link from MLVS	Decentralized with busbar trunking: - finishing sector, envelope filling Centralized with cables: - special machines, rotary machines, HVAC, process utilities, offices (2 switchboards), office air conditioning, social premises, maintenance
Presence of back-up generator	Criticality ≤ low Network availability: standard	No back-up generator
Presence of UPS	Criticality	UPS unit for IT devices and office workstations

Fig. D32 : Detailed single-line diagram (1 substation based on fig.D22)

Choice	Main criteria	Solution
MV/LV substation	Service conditions	indoor (dedicated premises)
MV switchboard	Offer availability by country	SM6 (installation in Europe)
Transformers	Service conditions	cast resin transfo (avoids constraints related to oil)
LV switchboard	Service conditions, service index for LV switchboards	MLVS: Prisma P Sub-distribution: Prisma
Busway	Load distribution	Canalis KS (fig.D32 or D33) Canalis KT for main distribution (fig D33)
UPS units	Installed power to be supplied, back-up time	Galaxy PW
Power factor correction	Reactive power to provide for the minimum up to the full load without harmonic (see chapter L for more information), presence of harmonics	LV automatic compensation (without detuned reactor).

“2 substation” solution

Main LV switchboard interconnected by a busway