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GENERAL INSTRUCTIONS FOR PREFORMA PF-4 / 5
ASSEMBLY AND USE OF PREFABRICATED PRIVATE
STATIONS (LV METERING)
IG-138-FR
version 02
02.10.2007
Page 24 of 28
ANNEX 1: SUBSTATION LAYOUT PLAN
Minimum recommended dimensions of the excavations:
Length (L)
Width (l)
Depth
PF-3 / PF-4
4.3 m
2.8 m
0.85 m
PF-5
5.1 m
3.0 m
0.85 m
Possible bottoms of excavations:
If good ground stability: sand or gravel.
If insufficient stability: lean blinding concrete (type 5% gravel-cement, hardness
<15 MPa).
If the soil is loose: concrete sand bed (50 mm), essential to make up for flatness
defects and ensure water drainage.
N.B.:
The difference in level of the excavation bottom must be +/- 10 mm.
