Special Arrangements - SDMO R 340 U User And Maintenance Manual

d) Safety guidelines
References: NFC 15-100:2002 (France) - IEC: 60364-5-54
In order to protect personnel against electric shocks, this generating set is equipped with a differential residual current protector
"factory" set to trigger instantly, with a sensitivity of 30 mA.
Any modification to this setting could endanger personnel. Any modification would render the user liable, and
must only be performed by qualified and authorised personnel.
When the generating set is disconnected from a facility after use, the master differential protector must be
returned to its "factory" settings, and this must be checked by trained personnel.
Important
For effective protection against electric shocks, the generating set needs to be earthed. To do this, use a copper wire, with a
minimum cross-section of 25 mm
socket and a galvanised steel earthing rod embedded vertically into the ground.
The earthing rod resistance value should comply with the values shown in the table below.
Note: use the highest differential setting from the installation as a guideline.
The resistance value is calculated in the following way:
Maximum resistance value of the earth socket R (Ω) according to the differential unit operational
current (operation time should not be longer than 1 second).
The Ul value: 25 V is required for work site installations, and livestock buildings, etc.
For a default voltage of 25 V and a default current of 30 mA, this rod must be of a minimum length of: see table below:
Nature of ground
Thick arable land,
moist compact ballast
Lean arable land,
Gravel, coarse ballast
Bare stony soils, dry sand,
impermeable rock
Note: For the United States (National Electrical Code reference NFPA-70).
The generating set must be earthed. To do this, use a copper wire with a minimum cross-section of 13.3 mm² (or AWG 6, at most)
connected to the generating set earth socket and a galvanised steel earthing rod fully embedded into the ground vertically.
This earthing rod embedded fully in the ground must have a minimum length of 2.5 m.
3.5.

Special arrangements

Generating sets are not fitted with protection against power surges caused by drops in atmospheric pressure or manoeuvring.
The company does not accept any responsibility regarding damage caused by these occurrences.
However, lightning conductors can be installed, on the understanding that this does not give total protection.
2
for a stripped cable and 16 mm
I Δn
differential
≤ 30 mA
100 mA
300 mA
500 mA
1A
3A
5A
10A
Length of
rod in
metres
1
1
To obtain an equivalent length, you can use several earthing rods
3.6 connected in parallel and set apart by at least their length.
Example: 4 interconnected 1 metre rods separated by 1 metre.
2
for an insulated cable, connected to the generating set earth
R = Ul
I Δn
Earth R
(Ω)
Ul: 50 V
500
500
167
100
50
17
10
5
26/285
Earth R
(Ω)
Ul: 25 V
> 500
250
83
50
25
8
5
2.5