Trefoil Cable Cleat Size Finder
Enter the overall diameter of one single-core cable to find the matching trefoil cable cleat size band. Trefoil cleats hold three single-core cables in a clover arrangement.
Which material: SS316L or aluminium?
- SS316L — SS316L stainless — for marine, offshore, coastal, chemical and washdown environments where chloride corrosion is the risk. Non-magnetic, highest corrosion resistance.
- Aluminium — Aluminium (LM6 / marine-grade) — for lower installed weight and easier handling on long cable routes, where the environment allows and galvanic isolation is managed.
Conductor size → approximate cable OD
| Conductor (mm²) | Approx. cable OD (mm) | Cleat band |
|---|---|---|
| 25 | ~18 | TC-1 |
| 35 | ~20 | TC-1 |
| 50 | ~22 | TC-2 |
| 70 | ~24 | TC-2 |
| 95 | ~27 | TC-2 |
| 120 | ~29 | TC-2 |
| 150 | ~32 | TC-3 |
| 185 | ~35 | TC-3 |
| 240 | ~39 | TC-4 |
| 300 | ~43 | TC-4 |
| 400 | ~48 | TC-5 |
| 500 | ~53 | TC-5 |
| 630 | ~59 | TC-6 |
| 800 | ~66 | TC-6 |
| 1000 | ~73 | TC-7 |
Full trefoil cleat size bands
| Band | Cable OD range (mm) |
|---|---|
| TC-1 | ø15 – 22 |
| TC-2 | ø22 – 30 |
| TC-3 | ø30 – 38 |
| TC-4 | ø38 – 47 |
| TC-5 | ø47 – 58 |
| TC-6 | ø58 – 70 |
| TC-7 | ø70 – 90 |
| TC-8 | ø90 – 130 |
Before you specify
- Cleats must withstand the peak short-circuit force between conductors — confirm the prospective fault current (kA) and spacing, not just the cable OD.
- Fix cleat spacing to the short-circuit withstand rating; closer spacing resists higher fault currents.
- For single-core AC circuits use non-magnetic cleats (SS316L or aluminium) to avoid hysteresis heating.
Frequently asked questions
How do I size a trefoil cable cleat?
Size by the overall diameter of one single-core cable, not the conductor cross-section. Find the cleat band whose range contains your cable OD. Then confirm the cleat is rated for the prospective short-circuit current and set the spacing accordingly.
SS316L or aluminium trefoil cleats — which should I choose?
Choose SS316L for marine, offshore, coastal, chemical or washdown environments where chloride corrosion dominates. Choose aluminium where lower installed weight matters on long routes and the environment is less aggressive, with galvanic isolation managed. Both are non-magnetic, which is required for single-core AC circuits.
Why must cable cleats be non-magnetic?
Single-core AC cables carry alternating current that induces eddy currents and hysteresis heating in any magnetic metal around them. A ferrous cleat would heat up and waste energy, so single-core circuits use non-magnetic SS316L or aluminium cleats.
Found your size group? Get a quote in 24 hours
Send us the OD, size group, quantity and mounting type — our engineers confirm the exact part number and quote within one working day.