Siemens 8DJH, Installation And Operating Instructions Manual

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7 | Installation
54/174 8DJH • Installation and Operating Instructions • Version 11 • 500-8384.9
Activity Cleaning agents
Removing dust Brush
Damp cleaning, drying Lint-free wiping cloths
Suction of drilling chips, construction waste, dust Vacuum cleaner with plastic tip for sensitive
components
7.4 Mounting paste
Use mounting paste only according to the installation instructions.
Use only the supplied or released mounting paste.
7.5 Tightening torques
If not stated otherwise, the following tightening torques apply to the switchgear:
Joint Material/material Thread Tightening torque
Metal joints Sheet-steel/sheet-steel
e.g.: front plates, top
plates, etc. M5 7 Nm
M6 (self-tapping) 12 Nm
M8 30 Nm
Earthing busbar Sheet-steel/copper M8 20 Nm
Copper/copper M8 20 Nm
Busbar interconnection Copper/copper M8 20 Nm
M10 40 Nm
Switchgear earthing Sheet-steel/cable lug M12
50 Nm
1)
Cable shield earthing M10
30 Nm
1)
Cable plugs M16
max. 50 Nm
1)
1)
The tightening torque depends on:
- Material of cable lug
- Information of sealing end manufacturer
- Information of cable manufacturer.
7.6 Comments on electromagnetic compatibility
To achieve appropriate electromagnetic compatibility (EMC), some basic requirements must be
observed while erecting the switchgear. This applies especially to the installation and connection
of external cables and wires.
Basic measures for ensuring EMC are already taken during design and assembly of the panels.
Among other things, these measures include:
▪ The low-voltage compartment is an integral part of the panel, which means that the
protection and control devices with the internal wiring are metal-enclosed.
▪ Reliable earth connections of the frame parts via toothed contact washers or locking
washers.
▪ Inside the panel, wires are laid in metal ducts.
▪ Spatial separation of sensitive signal wires from wires with high interference voltage levels.
▪ Limitation of switching overvoltages of inductive loads (e.g. relay or contactor coils, motors)
by means of protective circuits with diode, varistor or RC element.
▪ Within the low-voltage compartment, the secondary devices are mounted in defined zones.
▪ Shortest possible connection between corresponding modules in subracks.
▪ Consideration of the magnetic leakage fields of conductor bars and cables.
▪ Protection of subracks and wiring backplanes against interference by perforated shielding
plates.
▪ Large surface bonding between all modules and devices as well as bonding to the earthing
conductor of the switchgear assembly.
These measures basically enable proper operation of the switchgear itself. The planner or
operator of the switchgear must decide whether additional measures are required depending on
the electromagnetic environment where the switchgear is installed. Such measures must be
implemented by the installation company in charge.