TTR vs NYY Cable: What Is the Difference and Where Is Each Used?
Learn how TTR and NYY cables differ in voltage class, conductor design, flexibility and place of use, and which one to choose for each application.
What is the difference between TTR and NYY cable? TTR (H05VV-F) is a flexible PVC-insulated connection cable with fine-stranded conductors in the 300/500 V class; it is used for appliance, machine and extension connections. NYY (YVV) is a fixed-installation power cable in the 0.6/1 kV class with PVC insulation and a thick PVC outer sheath; it is used for building feeders, in cable trays and, with suitable protection, underground. In short, TTR is for connections that move and NYY is for fixed power distribution.
Comparison table
| Property | TTR (H05VV-F) | NYY (YVV) |
|---|---|---|
| Rated voltage | 300/500 V | 0.6/1 kV |
| Conductor | Class 5, fine-stranded copper | Class 1 or 2, solid or stranded copper |
| Insulation and sheath | PVC insulation, PVC outer sheath | PVC insulation, thick PVC outer sheath |
| Flexibility | Suitable for moving connections | For fixed installation |
| Place of use | Indoors; appliances, machines, extension leads | Indoors and outdoors, cable trays, underground with suitable protection |
| Catalog | TTR Cables | NYY Cables |
Which one should I choose?
- For connections that move or are plugged and unplugged, choose TTR: machine and appliance supply cables, extension and reel cables, temporary connections in a workshop. Where impact, oil or outdoor conditions are severe, rubber-sheathed H07RN-F types are preferred.
- For fixed power lines, choose NYY: building main feeders, panel-to-panel connections, lines running outdoors and in cable trays, and underground laying with mechanical protection.
- For flush or surface-mounted fixed building wiring, neither TTR nor NYY is needed; NYM (antigron) cables are used for this.
- Where low smoke and halogen-free burning are required (hospitals, shopping centres, tunnels, enclosed car parks), N2XH cables are chosen instead of NYY.
Cross-section and current-carrying capacity
For both cable types the current-carrying capacity depends on the cross-section, number of cores, installation method and ambient temperature, so the current a TTR and an NYY of the same cross-section can carry cannot be given as a single number. On long runs the voltage drop must also be checked. You can verify the selection with the cable ampacity and voltage drop calculators.
How to read the cable marking
The printing on the cable sheath is the safest way to tell the two types apart. TTR cables are marked H05VV-F or TTR with the number of cores and cross-section (for example 3G2.5 or 3x2.5). NYY cables are marked NYY or YVV with the 0.6/1 kV voltage class, number of cores and cross-section. Do not identify a cable by its colour or thickness alone.
Related guides
- What Is TTR (H05VV-F) Cable? Properties, Uses and Selection
- What Is NYY Cable? Properties, Uses and Selection
- NYA, NYAF and H05VV-F cable difference
- What is the difference between NYY and N2XH cables?
Frequently asked questions
Can TTR cable be laid underground?
No. TTR is not designed for underground or permanent outdoor conditions. Underground lines use sheathed cables in the 0.6/1 kV class, such as NYY, laid with mechanical protection.
Can NYY cable be used as an extension cable?
No. The conductors of NYY are designed for fixed installation and do not withstand continuous bending. Moving connections use flexible cables such as TTR or, in severe conditions, H07RN-F.
Antigron, TTR or NYY?
Choose antigron (NYM) for flush or surface-mounted fixed indoor wiring, TTR for moving appliance and machine connections, and NYY for power lines outdoors, in cable trays and underground.
How can TTR and NYY be told apart?
Check the printing on the sheath: TTR cables are marked H05VV-F or TTR, NYY cables NYY or YVV with 0.6/1 kV. If the marking cannot be read, the conductor also gives a clue: fine-stranded in TTR, thicker strands or a solid wire in NYY.