Guidelines for the Safe Use of Cables

Safe Use of SAB Cables

 The cables manufactured by SAB Bröckskes are only appropriate for the transmission of electric energy for supply and signaling purposes.

First and foremost, the applicable construction and installation regulations for the respective machine or equipment must be followed. The valid VDE regulation 0100 serves as a fundamental reference. Additionally, the following safety guidelines must be observed when using cables.

For each cable type, the “Technical Data” section provides information on various parameters, which are also referenced in the following standards, among others:
Nominal voltage, Peak operating voltage HD 516
Test voltage VDE 0250 T1, EN 50525-1 as well as relevant cable standards
Minimum bending radius HD 516
Temperature range HD 516
Fire performance Standards of series IEC 60332 as well as relevant cable standards
Resistances IEC 60811-404 as well as relevant cable standards
Further special technical data  
The safe application is described under “security requirements” and “boundary conditions”
Under “Security Requirements,” you will find information on various aspects that are also covered in the following standards, among others:
Basic requirements HD 516 pos. 4.1
General requirements HD 516 pos. 4.2
Current-carrying capacity for undisturbed service VDE 0298-4 pos. 5
Operating conditions VDE 0298-4 pos. 5.3.1
Ambient conditions VDE 0298-4 pos. 5.3.3
Requirements for fixed laying HD 516 pos. 4.3
Requirements for flexible cables HD 516 pos. 4.4

Standards for Operating Conditions

Under “Boundary Conditions,” you will find information on various aspects that are also referenced in the following standards, among others:
Operating conditions HD 516 pos. 5
Voltage HD 516 pos. 5.1
Current-carrying capacity HD 516 pos. 5.2
Capacity, cables with a nominal voltage up to 1000 V and heat resistant cables VDE 0298-4 table 11
Conversion factors for deviating ambient temperatures VDE 0298-4 table 17+18
Conversion factors for the accumulation on walls, in tubes and conduits, on the floor and at the ceiling VDE 0298-4 table 21
Conversion factors for multi-core cables with conductor cross sections up to 10 mm² VDE 0298-4 table 26
Thermal influences HD 516 pos. 5.3
Mechanical stress HD 516 pos. 5.4
Tensile load HD 516 pos. 5.4.1
Bending load HD 516 pos. 5.4.2
Compression stress HD 516 pos. 5.4.3
Torsional stress HD 516 pos. 5.4.4
Compatibility HD 516 pos. 5.5
Application in rooms and in the open air HD 516 annex A
Stress classification HD 516 annex B
Construction of strands IEC 60228 + VDE 295
In addition to the generally known technical rules, please pay special attention to the following guidelines for the application of our products.
VDE...
0100, 0105, 0106, 0108, 0110, 0113, 0116,
0165, 0166, 0170, 0171, 0271, 0298, 0700,
0720, 0727, 0730, 0737, 0740, 0745, 0750,
0800, 0804, 0805, 0839, 0860, 0891, 1000, etc.
Under each item group, you will find additional instructions and a description of the specific application possibilities for our cables.

Security Requirements

Basic Requirements
Cables are considered safe when used as intended and do not pose any unacceptable risk to life or property. Unless otherwise specified, insulated cables should only be used for transmitting and distributing electrical energy.
General Requirements
Cables must be selected to accommodate the voltages and currents present in the machines, equipment, or components they are intended for, under all expected operating conditions. They should be designed, installed, protected, and maintained to prevent any risks or damage.
Carrying Capacity for Undisturbed Service (General Info)
The cable cross-section must be selected to ensure that the specified current-carrying capacity does not cause the conductor to exceed the permissible service temperature. The heating and current-carrying capacity of a cable depend on its construction, material properties, and operating conditions. Additional heat sources, such as cable bundling, heating ducts, or solar radiation, must be considered and mitigated. When using covers, proper air circulation must be maintained.
Operating Conditions
The temporary flow of current defines the operating conditions. Continuous operation refers to a constant current that is sufficient to reach the thermal equilibrium of the electrical equipment without any time limitations. The capacity values of cables are based on continuous operation, ensuring the conductor reaches but does not exceed its permissible operating temperature.
Environmental conditions
Environmental conditions are determined by factors such as ambient temperature, heat dissipation, and heat radiation. The ambient temperature refers to the surrounding air temperature without any load on the cable, with a standard reference point of +30°C. Cable operating conditions can be influenced by heat dissipation in enclosed spaces, cable ducts, or similar environments, as well as by heat radiation, such as exposure to solar radiation.

Conditions and Requirements for Fixed Installations

The Fixed Installation of Cables Requires, Among Other Considerations:
•  Cables should not be installed in direct or close contact with hot surfaces unless specifically designed for such applications.
•  Cables are not suitable for direct underground installation.
•  Proper fixation of cables is essential, with the fixing distance determined by the cable’s weight.
•  Mechanical fixing devices must not cause damage to the cable.
•  Long-term use may result in cable damage during removal due to the natural aging of insulation and jacket materials, which can become brittle over time.
Requirements for Flexible Cables
•  Flexible cables should be used for mobile electrical equipment.
•  The connection cable length must be selected to ensure the proper activation of short-circuit protective devices.
•  For mobile electrical equipment, the cable should be kept as short as possible.
•  Excessive stress from tension, pressure, abrasion, torsion, or kinking must be avoided.
•  Cables must not be damaged by strain relief or connection devices.
•  Cables should not be placed under carpets or other objects, as this poses a risk of overheating and mechanical damage from foot traffic, furniture, or operational equipment.
•  Cables must not be in direct or close contact with hot surfaces.
•  For additional requirements, refer to HD 516 S2, section 4.4.

Operating & External Conditions

Operating Conditions:
The cables used must be suitable for the corresponding operating conditions and comply with the device protection class requirements.
Operating conditions include, but are not limited to:
Voltage Current
Safety apparatus Cable accumulation
Type of laying Accessibility
External Conditions
The used cables have to be appropriate for all possible external impacts.
External conditions include, but are not limited to:
Ambient temperature Rain
Steam or water Presence of corrosive, polluting or other chemical bodies
Mechanical stress (e.g. sharp edges of metal constructions) Animals (e.g. rodents)
Plants / xxxxxxxxxxxxxx (e.g. mold fungus) Radiation (e.g. solar radiation)
Note:
In this context, color plays a crucial role. Black provides significantly greater protection against radiation compared to other colors.
Voltages:
The nominal voltage of a cable refers to the voltage for which it is designed and determines the electrical testing parameters. It is expressed in volts as a ratio of two values: Uo/U.
•  Uo is the root mean square (r.m.s.) voltage between the external conductor and earth (such as the cable’s metal shielding or surrounding medium).
•  U is the r.m.s. voltage between two external conductors in a multi-core cable or a system of single-core cables.
In an alternating current (AC) system, the cable’s nominal voltage must be at least equal to both Uo and U of the system.
In a direct current (DC) system, the system’s nominal voltage must not exceed 1.5 times the cable’s nominal voltage.
Note: The operating voltage of a system may continuously exceed the nominal voltage by up to 10%

Calculation of Cable Section and Conversion Factors for Cables

Current carrying capacity of electric cables
For cable dimensioning, the nominal cross-section of each conductor must be selected so that its current-carrying capacity is at least equal to the maximum continuous current flowing through it under normal operating conditions. The permissible temperature limits for the insulation and jacket materials of the respective cable types must not be exceeded.
Additionally, the installation method of the cable is a key factor in determining the allowable load current. The following conditions, among others, must be taken into account:
Allowed operating temperature at conductor Ambient temperature
Accumulation, bundles and laying of the cable Number of conductors
Wound up cables Current frequency
Impacts of ripple currents (deviating from 50 Hz)
Calculation of Cable Section and Conversion Factors for Cables
Examples to calculate the maximum current carrying capacity acc. to VDE 0298-4:2023-06
Cable type: CC 500
Item no. L0200-0315
Nominal voltage Uo/U 300/500 V
Temperature range up to +70°C
Construction 3 G 1.5 mm²
Application:
For this installation, the current-carrying capacity should be calculated under the following conditions: an ambient temperature of +50°C, two loaded cores, and installation alongside three other cables on the floor. All four cables have the same dimensions and are in direct contact with each other.
Tables to consider VDE 0298-4: table 10, 11, 17 and 22
Current-carrying capacity The current-carrying capacity for two simultaneously loaded cores with a cross-section of 1.5 mm² at temperatures up to +30°C, according to Table 10 and 11/5, is 18A.
Ambient temperature factor Factor for deviating ambient temperature +50°C acc. to table 17: 0.71 (18A x 0.71 ≈ 12.8A)
Laying factor Factor for the laying of four of these cables on the floor in contact: 0.75 (12.78A x 0.75 ≈ 9.6A)
Maximum current load The current load for the described cable shall not exceed a value of 9.5A.
Cable type: DR 720 P Highflex
Item no. L0720-0640
Nominal voltage Uo/U 0.6/1 kV
Temperature range up to +90°C
Construction 6 G 4.0 mm²
Application:
For this reeling cable, the current-carrying capacity must be calculated under the following conditions: an ambient temperature of +65°C, five loaded cores, and installation in three layers on a motor reel.
Tables to consider VDE 0298-4: table 10, 11, 18, 27 and 28
Current-carrying capacity Current carrying capacity for a nominal section of 4.0 mm² at a temperature up to +50°C acc. to table 10 and 11/5: 34A
Number of cores factor Factor for deviating number of cores (five cores) acc. to table 27: 0.75 (34A x 0.75 = 25.5A)
Ambient temperature factor Factor for deviating ambient temperature +65°C according to table 18: 0.79 (25.5A x 0.79 ≈ 20.1)
Installation factor Factor for the installation in three layers on a motor reel acc. to table 28: 0.49 (20.1A x 0.49 ≈ 9.9A)
Maximum current load The current load for the described cable shall not exceed a value of 9.8A.
Calculation of cable section:
The cable cross-section must be selected not only based on current-carrying capacity but also to meet requirements for protection against hazardous body currents, overloads, short circuits, and voltage drops. Prolonged operation of cables above the recommended application temperature can cause significant damage, potentially leading to premature failure and a substantial decline in cable performance.

Cable Performance and Safety Considerations

Thermal influences:
Cables must be selected, laid, and installed in a manner that allows for proper heat dissipation, preventing any fire risk to surrounding materials. The maximum temperature limits for each cable type are specified in the catalog and must not be exceeded due to the combined effects of internal current-generated heat and external environmental conditions.
Mechanical stress:
Any potential mechanical stress that could cause damage to the installed cable must be assessed and accounted for before installation.
Tensile load:
The following tensile load limits for each conductor must not be exceeded:
Maximum tensile load 1000 N per conductor, unless otherwise approved by SAB Bröckskes.
Fixed applications 50 N/mm² for the installation of cables used in fixed applications.
Flexible cables / permanently installed electrical circuits 15 N/mm² for the static tensile load of flexible cables and for fixed installations in permanently installed electrical circuits.
If these values are exceeded, the use of separate strain relief elements or similar solutions is recommended. The connection of such strain relief elements must be carried out without causing damage to the cable.
For flexible cables exposed to dynamic tensile loads (e.g., those subject to tensile forces due to mass inertia, such as on unwinding spools), the allowable tensile load or expected service life must be determined in consultation between the user and SAB Bröckskes.
Guidelines for vertical cable installation without intermediate fixation can be found in EN 50656-1, section 5.6.2.
Bending load:
The inner bending radius of a cable must be selected to prevent any damage. The specified inner bending radii for different cable constructions are listed in Table 6 of HD 516. If a smaller bending radius than indicated in the cable catalog is required, approval must be obtained from SAB Bröckskes.
When stripping the cable jacket, care must be taken to avoid damaging the conductor, as this can significantly impair the cable’s bending characteristics.
The specified bending radii apply to ambient temperatures of (20 ± 10)°C. For different temperature conditions, please consult SAB Bröckskes.
Bending directly next to external or internal fixation points should be avoided.
Pressure stress:
Any pressure that could cause damage to the cable must be avoided.
Torsional stress:
Flexible cables are generally not designed for torsional stress. If torsional stress is unavoidable, the cable’s construction and installation method must be coordinated between the user and SAB Bröckskes.
Compatibility:
When selecting and installing cables, the following factors must be considered:
•  Avoid mechanical and electrical interference between adjacent electrical circuits.
•  Prevent heat loss and chemical or physical interactions between cable materials and surrounding materials, such as construction or decorative elements, insulating tubes, and fixing devices.
•  Consider the impact of current-generated heat on conductor materials and connections.
For further details, refer to Tables 3A, 3B, 4A, and 4B of HD 516.

Installation Locations

Room types
Electric shops Rooms primarily used for operating electrical equipment, with access restricted to trained personnel, such as switch rooms.
Closed electric shops Rooms exclusively for electrical equipment operation, typically locked, and accessible only to authorized personnel, such as closed switch and distribution systems.
Dry rooms Spaces without condensation where the air is not saturated with humidity, such as living rooms and hotel rooms.
Damp rooms Environments where operational device safety may be compromised by humidity, condensation, chemicals, or similar factors, such as large kitchens.
General Notes
Rooms can only be classified into one of the mentioned categories after a thorough inspection of their conditions and operational environment. If high humidity is present in a specific area but the room remains dry due to effective ventilation, it does not necessarily need to be classified as a damp room.
Application in rooms and in the open air
These terms must be interpreted in relation to the boundary conditions, such as minimum and maximum operating temperatures and the impact of ambient temperatures, as determined by the design and intended application.
Terms for application types
Application in rooms The cable is installed or connected to a device that is typically located inside a building within a “planned environment.” The building may be used for business, industrial, or residential purposes.
Limited application in the open air The cable is suitable for short-term outdoor use within a “planned environment,” such as for a lawn mower.
Permanent application in the open air The cable is designed to withstand various outdoor conditions, including different weather elements, within a “planned environment.”

Application Areas / Storage / Handling & Transport

Stress Classification
The term “stress” refers to the use of cables in specific environments, their connection to or installation in devices, and exposure to various external factors in those areas. Based on mechanical influences and general criteria, “stress” is classified into four categories.
1. Very Light Stress Areas where the risk of mechanical damage and stress is minimal, such as electric razors.
2. Light Stress Areas with a low risk of mechanical damage and stress, such as hair dryers.
3. Normal Stress Areas where cables are exposed to minor mechanical stress, with a low risk of mechanical damage, such as small stoves.
4. Heavy Stress Areas where mechanical stress or the risk of mechanical damage is moderate, such as machines used on construction sites.
4a. Heavy Stress
(only for multi-conductor cables)		 Similar to heavy stress applications but specifically related to components of production systems, including machine tools and handheld mechanical devices, such as switchboards of a production machine.
Storage as well as handling/transport
Storage Conditions Cables unsuitable for outdoor use must be stored indoors in dry rooms. Some flexible cable types are particularly sensitive to humidity.
Protection Against Moisture Cable ends stored outdoors or exposed to open-air conditions must be sealed to prevent moisture ingress.
Temperature Limits The maximum recommended storage temperature is 40°C and must not be exceeded.
Temperature Limits The minimum laying and handling temperature must be adhered to.
Temperature Limits Some cable manufacturers may specify a higher maximum storage temperature or a lower minimum laying and handling temperature for specific cable types.
Temperature Limits If no minimum laying and handling temperature is specified by the manufacturer, a default minimum of 5°C should be assumed.
Handling and Transport Minimize mechanical stress such as vibration, impact, bending, and torsion during handling and transport.
Handling and Transport If cable temperature falls below the minimum laying temperature or exceeds the 40°C storage limit, additional precautions must be taken to prevent potential cable deterioration. For guidance, consult the cable manufacturer.
Safe Handling of Drums and Wrapped Cables Appropriate measures must be in place to ensure safe handling of cables stored on drums or wrapped bundles, preventing cable damage and reducing risks to people nearby.