defa.com
8
English
9
English
defa.com
7. Margin of safety
MARGIN OF SAFETY FOR SITE MAIN FUSE
The power sharing system makes it possible to deviate from a strict principle in the
regulations, with concurrence factor of 1. Make sure the facility in planning and in practice
never exceeds its limitations.
For installations with power-sharing systems, DEFA recommends the use of conservative
safety margins. All values should be rounded down and have at least 5% margin of safety
on site and fuse size of the charging point.
Please note that the margin of safety must be calculated based on the fuse size without
the fixed building loads (lighting, heating etc.) deducted.
NB! The signalling between the vehicle and the charging infrastructure will normally never be
more precise than ± 5%. DEFA therefore recommends a minimum of 5% margin of safety.
NUMBER OF CHARGE POINTS
The standardization for charging electric vehicles limits the number of vehicles that can
charge simultaneously. Because of this, every vehicle should at all times have at least 6A
available.
A facility is normally defined as overnight charging in shared car parks, such as home
cooperatives. The management principle requires a power allocation for charging with an
overload protection that does not supply other fixed loads.
!
SUPPLY FROM 230V / 3-PHASE / DELTA IT NETWORK
Site current
per phase [A]
Site current per phase with
5% margin of safety [A]
Maximum number of
charging vehicles per phase
Maximum number of
charging vehicles in total
32
30
2
6
35
33
3
9
40
38
3
9
50
47
4
12
63
59
5
15
80
76
7
21
100
95
9
27
125
118
11
33
150
142
13
39
180
171
16
48
200
190
18
54
250
237
22
66
300
285
27
81
350
332
31
93
400
380
36
108
Allowing the system to create queues is an option if there are more charge points installed
than recommended in a facility with limited capacity. Queuing is supported by the CLU, but
since certain types of vehicles do not wake from hibernation when taken out of the queue,
the maximum number of charging vehicles should never exceed what is advised in the
tables below.
