Example: electrical installation in a printworks

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
Atmosphere, environment	IP: standard (no dust, no water protection) IK: standard (use of technical pits, dedicated premises) °C: standard (temperature regulation)
Service index	211
Offer availability by country	No problem (project carried out in France)
Other criteria	Nothing particular

Criteria	Category
On-site work time	Secondary
Environmental impact	Minimal: compliance with European standard regulations
Preventive maintenance costs	Standard
Power supply availability	Level I

Choice	Main criteria	Solution
Connection to network	Isolated site	single branch circuit
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: NO link between MLVS if 2 substations: interconnected switchboards
MV Generator	Site activity	No

Fig. D29: Two possible single-line diagrams

“1 substation” solution

Choice	Main criteria	Solution
Layout	Atmospheric constraint	Dedicated premises
Centralized or decentralized 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 servers and office PCs
LV circuit configuration	2 transformers, possible partial redundancy	Two-pole, variant 2 ½ MLVS + NO link (reduction of the Isc by MLVS, no redundancy process (≤ weak) sheddable circuit for non-critical loads

Fig. D30: Detailed single-line diagram (1 substation)

Choice	Main criteria	Solution
MV/LV substation	Atmosphere, environment	indoor (dedicated premises)
MV switchboard	Offer availability by country	SM6 (installation produced in France)
Transformers	Atmosphere, environment	cast resin transfo (avoids constraints related to oil)
LV switchboard	Atmosphere, IS	MLVS: Prisma + P Sub-distribution: Prisma +
Busbar trunking	Installed power to be supplied	Canalis KS
UPS units	Installed power to be supplied, back- up time	Galaxy PW
Power factor correction	Installed power, presence of harmonics	LV, standard, automatic (Average Q, ease of installation)

“2 substation” solution

Ditto apart from:
LV circuit: 2 remote MLVS connected via busbar trunking

Fig. D31: Detailed single-line diagram (2 substations)

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