In recent years, the use of EMC variable frequency drive motors has been increasing, both…
TOPDRIVE® ROZ1-K / 2XSL(ST)CH, the power supply cable for motors with VFD drives
Variable frequency drive (VFD) motors require specialized power cables to handle electromagnetic interference (EMI) and ensure optimal performance. Standard industrial cables often fail to provide adequate shielding, leading to equipment malfunction, motor bearing damage, and system inefficiency. TOPDRIVE® VFD ROZ1-K VFD EMC 2XSL (ST)CH cable has been specially engineered by Top Cable, a European cable manufacturer with over 30 years of experience, to address these critical challenges in industrial VFD installations.
This high-performance VFD power cable features a symmetrical 3C+3G conductor configuration, double-layer electromagnetic screening with 100% coverage, and XLPE insulation rated for 0.6/1 kV applications. Manufactured in compliance with IEC 60502-1 and CPR Cca standards, TOPDRIVE® ROZ1-K / 2XSL(ST)CH ensures electromagnetic compatibility (EMC) while delivering superior flexibility, halogen-free safety, and long-term reliability for demanding industrial environments.
DESIGN:
1 – Copper conductor class 5 (flexible).
2 – Protective conductor: the earth conductor is divided into three conductors (3G).
3 – XLPE insulation.
4 – Double shield of overlapping aluminium-polyester tape, plus a braid of tinned copper wires. 100% shielding.
5 – Halogen-free polyolefin (LSZH) outer sheath.
WHY VFD MOTORS REQUIRE SPECIALIZED POWER CABLES
Understanding VFD operation and EMI challenges
Variable frequency drives convert standard AC power into variable frequency and voltage output through pulse width modulation (PWM). This switching process generates high-frequency harmonics and common mode currents that standard cables cannot adequately handle. Without proper shielding, these electrical disturbances cause:
- Motor bearing currents that reduce bearing lifespan by up to 50%.
- Electromagnetic interference (EMI) affecting nearby electronic equipment.
- Voltage reflections at motor terminals creating insulation stress.
- Ground loop currents disrupting control systems.
The right cable selection for best VFD performance
According to industry research, 25% of global electrical energy consumption comes from electric motors. VFD technology improves motor efficiency by 20-40%, but only when paired with appropriate cabling. The cable acts as the transmission medium between the drive and motor, with its electrical characteristics directly impacting system performance, energy efficiency, and equipment longevity.
TOPDRIVE® ROZ1-K / 2XSL(ST)CH TECHNICAL SPECIFICATIONS AND DESIGN FEATURES
Symmetrical 3C+3G conductor configuration
The TOPDRIVE® ROZ1-K / 2XSL (ST)CH employs a symmetrical arrangement of three phase conductors (3C) plus three ground conductors (3G) positioned alternately around the cable core. This geometric configuration:
- Minimizes common mode current (CMC) by balancing electromagnetic fields.
- Provides multiple low-impedance ground paths for fault current dissipation.
- Reduces ground loop impedance by up to 40% compared to single ground designs.
- Ensures equal current distribution during VFD operation.
Conductor specifications:
- Material: Bare copper (99.9% purity).
- Class: 5 (fine-stranded for maximum flexibility.
- Cross-sections available: 1.5 mm² to 240 mm².
- Temperature rating: 90°C continuous, 250°C short circuit.
Double-Layer EMC screening
TOPDRIVE® ROZ1-K / 2XSL(ST)CH features a comprehensive dual-screen construction providing 100% electromagnetic coverage:
First layer: Overlapping aluminum-polyester tape with minimum 20% overlap, creating a continuous metallic barrier against radiated EMI from 1 kHz to 1 GHz frequency range.
Second layer: Tinned copper braid (optical coverage ≥85%) providing:
- Low DC resistance for effective grounding.
- Mechanical protection for the aluminum tape.
- Corrosion resistance through tin plating.
- Enhanced flexibility for cable routing.
This double-screening approach achieves transfer impedance values below 10 mΩ/m at VFD operating frequencies, significantly outperforming single-shield designs.
XLPE insulation for superior electrical performance
Cross-linked polyethylene (XLPE) insulation offers critical advantages over PVC in VFD applications:
- Lower dielectric constant (εr = 2.3 vs PVC’s 7.4) reducing capacitance by 68%.
- Higher temperature rating (90°C continuous vs PVC’s 70°C).
- Superior voltage spike resistance withstanding transients up to 3 kV.
- Reduced dielectric losses improving overall system efficiency.
- Better aging characteristics maintaining properties over 30+ year lifespan.
Halogen-Free LSZH outer sheath
The polyolefin-based outer sheath provides:
- Flame retardancy per EN 50399 (CPR Cca rating).
- Zero halogen content (compliant with IEC 60754-1).
- Low smoke emission (>80% light transmittance per IEC 61034).
- Non-corrosive combustion gases (pH ≥4.3, conductivity <10 μS/mm).
- UV resistance for outdoor/indoor installations.
- Oil and chemical resistance for industrial environments.
INSTALLATIONS WHERE TOPDRIVE® ROZ1-K / 2XSL(ST)CH VFD (EMC) 0,6/1 kV CABLE IS SUGGESTED FOR USE
TOPDRIVE® ROZ1-K / 2XSL(ST)CH VFD EMC cable has proven reliability in:
Manufacturing and automation:
- CNC machining centers with servo motors.
- Automated assembly line conveyors.
- Robotic welding and material handling systems.
- Packaging machinery with variable speed control.
Process industries:
- Variable speed pump systems for water/wastewater treatment.
- Chemical processing with corrosion-resistant requirements.
- Petrochemical refineries (Oil & Gas applications).
- Mining operations with mobile and fixed equipment.
HVAC and building systems:
- Large commercial HVAC systems with VFD compressors.
- Chilled water pumping systems.
- Ventilation fans with demand-based control.
- Building automation with multiple VFD installations.
Power generation:
- Wind turbine pitch and yaw control systems.
- Solar tracking systems with motor drives.
- Auxiliary systems in power plants.
- Energy storage system (ESS) cooling pumps.
Comparing VFD Cable Options
| Feature | TOPDRIVE® ROZ1-K / 2XSL(ST)CH | Standard VFD cable | Unscreened |
| EMC Compliance | ✓ Full (IEC 60502-1) | Partial | ✗ None |
| CPR compliance (fire performance) | Cca -s1a, d1, a1 Excellent | Limited | Basic |
| Screen | Double (100%) | Single/None | None |
| Ground System | 3C+3G symmetrical | 1G standard | 1G standard |
| Insulation | XLPE (90°C) | XLPE (90°C) | PVC (70°C) |
| VFD Suitability | Excellent | Limited | Not recommended |
| Bearing Current Protection | ✓ Yes | Minimal | ✗ No |
| Cable Length Capability | Up to 300m* | Up to 100m | <50m |
| EMI Emission Level | Very Low | Moderate | High |
WHERE TO BUY TOPDRIVE® ROZ1-K / 2XSL(ST)CH VFD (EMC) FOR FREQUENCY INVERTERS?
To buy TOPDRIVE® ROZ1-K cable on drums in various formats, please see our sales conditions for Electrical Distributors and Wholesalers here. We can also put you in touch with your nearest Top Cable distributor.
Some of the most common cross-sections with immediate stock are as follows:
| Cable | Conductor cross-section (mm2) |
| TOPDRIVE® ROZ1-K / 2XSL(ST)CH VFD (EMC) | 3 x 6 + 3 G 1,5 |
| TOPDRIVE® ROZ1-K / 2XSL(ST)CH VFD (EMC) | 3 x 16 + 3 G 2,5 |
| TOPDRIVE® ROZ1-K / 2XSL(ST)CH VFD (EMC) | 3 x 16 + 3 G 6 |
| TOPDRIVE® ROZ1-K / 2XSL(ST)CH VFD (EMC) | 3 x 50 + 3 G 10 |
| TOPDRIVE® ROZ1-K / 2XSL(ST)CH VFD (EMC) | 3 x 120 + 3 G 16 |
| TOPDRIVE® ROZ1-K / 2XSL(ST)CH VFD (EMC) | 3 x 240 + 3 G 50 |
| TOPDRIVE® ROZ1-K / 2XSL(ST)CH VFD (EMC) | 4 G 2,5 |
If you need to consult additional technical aspects of this cable, such as its maximum admissible current or voltage drop, please contact us.
PARTNER WITH A LEADING EUROPEAN VFD CABLE MANUFACTURER
Since 1992, Top Cable has specialized in manufacturing high-performance industrial cables for demanding worldwide applications. Our TOPDRIVE® ROZ1-K / 2XSL(ST)CH VFD EMC cable represents over three decades of engineering expertise in electromagnetic compatibility and motor power supply solutions.
Why choose Top Cable as your VFD cable supplier?
- European manufacturing excellence with ISO 9001 certified facilities
- Immediate stock availability of common cross-sections from 1.5mm² to 240mm²
- Technical support team with in-depth VFD application knowledge
- Custom cable solutions for specialized VFD requirements
- Complete documentation including DoP, test certificates, and technical data sheets
Ready to specify TOPDRIVE® ROZ1-K / 2XSL(ST)CH for your next VFD installation?
Contact our technical sales team for:
- Technical data sheets and installation guidelines.
- Connection to your nearest Top Cable authorized distributor.
TOPDRIVE® ROZ1-K / 2XSL(ST)CH
Flexible EMC LSZH screened cable for Variable Frequency Drive motors
FREQUENTLY ASKED QUESTIONS (FAQ) ABOUT TOPDRIVE® ROZ1-K / 2XSL(ST)CH VFD CABLE (EMC)
Are all VFD cables the same and what advantages does the TOPDRIVE® ROZ1-K / 2XSL(ST)CH cable have over other R0Z1-K / 2XSL(ST)CH cables?
Top Cable’ s TOPDRIVE® ROZ1-K / 2XSL(ST)CH cable design is the one with the highest performance, favouring earth leakage and avoiding the effect of voltage peaks:
Flexible copper conductor (class 5), which gives the cable maximum flexibility.
Arrangement of conductors and earth three plus three (3C+3G) to avoid current leakage through earth.
Cross-linked polyethylene insulation (XLPE) with performance far superior to PVC.
Double aluminium-polyester screen that offers 100% shielding and thus prevents the emission of electromagnetic waves from our cable to the rest of the equipment.
Tinned copper mesh, with anti-corrosion features and better installation.
Halogen-free outer sheath (LSZH) with the highest CPR classification (Cca – s1a, d1, a1) with low emission of fumes and corrosive gases in case of fire to protect people and equipment.
This is why Top Cable’s TOPDRIVE® R0Z1-K cable is recommended by leading manufacturers of variable frequency drives and also by GAMBICA, the British Capital Goods Association.
If you are looking for a cable for powering motors with variable frequency drives of the highest performance, please contact us.
Why is it recommended to use XLP cables (as opposed to PVC) to power VFD motors?
To avoid voltage peaks, we should use a cable with XLPE insulation (90ºC) instead of one with PVC insulation (70ºC). In addition, the dielectric coefficient of XLPE (2.3) is much lower than that of PVC (7.4), which also reduces the capacitive effect and therefore the magnitude of the reflected waves.
Can I install an unshielded cable to power motors with VFD drives?
As mentioned above, a cable with an inadequate shield (or no shield) can act as an antenna and be a source of radiated emissions. RV, RV-K, or RZ1-K cables do not guarantee electromagnetic compatibility and impedance matching, and are therefore not suitable for powering VFD motors.
Similarly, it is not advisable to install single core cables, even if they are shielded, as it is necessary to compensate for inductions and respect the symmetrical configuration of the 3C+3G phases.
Where can I find the technical specification of the TOPDRIVE® ROZ1-K cable in PDF format?
Here is the PDF of the summary technical specification of the TOPDRIVE® R0Z1-K cable. If you need to consult additional technical aspects of this cable, such as its maximum admissible current or voltage drop, please contact us.
What is the price of the TOPDRIVE® ROZ1-K rubber cable?
At Top Cable you will get the highest quality cables, with the best prices and the best service for TOPDRIVE® R0Z1-K rubber electrical cable drums and spools. Contact us.
What is the colour code of the TOPDRIVE® ROZ1-K cable?
The standardised identification of the insulated conductors of the TOPDRIVE® R0Z1-K cable is as follows:
3 x + 3 G: Grey + brown + black + Yellow/Green (3G) (from 6 mm2).
4 G : Grey + brown + black + Yellow/Green (up to 4 mm2).
What features does the TOPDRIVE® ROZ1-K cable offer against fire?
Flame non-propagation according to UNE-EN 60332-1 / IEC 60332-1.
Fire non-propagation according to UNE-EN 60332-3 / IEC 60332-3 and EN 50399.
CPR reaction to fire: Cca-s1a, d1, a1, according to EN 50575.
Halogen-free according to UNE-EN 60754-1 / IEC 60754-1.
Low emission of corrosive gases according to UNE-EN 60754-2 / IEC 60754-2.
Low smoke emission according to UNE-EN 61034 / IEC 61034:
Light transmittance > 80%.
What certifications does the TOPDRIVE® ROZ1-K cable meet? What is its CPR rating? Where can I check its DoP?
TOPDRIVE® R0Z1-K cable has been designed according to the IEC 60502-1 / IEC 60092-353 reference standard and complies with the European CPR (Construction Products Regulation) Cca – s1a, d1, a1. You can consult the Declaration of Performance (DoP) at this link. In addition, the TOPDRIVE® R0Z1-K cable is CE / UKCA / BUREAU VERITAS / DNV-GL / ABS /LLOYD’S REGISTER / RoHS /.
What precautions should be taken into account during the installation of a TOPDRIVE® ROZ1-K cable for VFD applications?
Certain precautions must be taken during installation:
Always respect the bending radius of the cable. Radii smaller than the minimum indicated may cause damage or breakage to the outer sheath.
Adequacy of the laying. The cable must be laid carefully, taking care not to damage the cover in irregular areas, sharp edges, etc.
Fixings/Fastenings. Adapt the fixings so that the cable adopts a natural position in the laying to avoid stress concentration on the roof. Allow a certain degree of freedom of movement and avoid excessively tight cable ties.
How does a variable frequency drive (VFD) work?
A Variable Frequency Drive (VFD) is a system for controlling the rotational speed of an alternating current (AC) motor by controlling the power frequency supplied to the motor.
An electric motor rotates its rotor according to the parameters achieved by the voltage and frequency of the electrical power supplied to the motor. Internationally, there are different mains voltages, such as 400 V (three-phase), 380 V (three-phase), etc., and frequencies of 50 or 60 Hertz. By varying the voltage and/or frequency, the performance of the motor, including the speed, varies. It is usually difficult to change the voltage or frequency without auxiliary equipment.
To vary the voltage and frequency effectively, a variable frequency drive is used. Normal power is supplied to the VFD and the output of the VFD is fed to the electric motor. The VFD has controls that can be adjusted to control the speed of the motor.
A VFD provides precise control of the speed and torque of an AC motor through pulse width modulation (PWM). In a VFD system, it is critical to choose the right cable for best performance, maximum energy efficiency and long life.
