Which SPE solutions are preferable compared to existing communication standards?
Single Pair Ethernet (SPE) is seen as one of the key trends shaping the future of industrial communications. Advantages of this new connection technology with only one pair of wires include fast data transmission, less space required and lower costs. But where will it be deployed in the future, what cable types will be needed, and how will SPE perform compared to existing communications standards? HELUKABEL addressed these questions in a webinar entitled “Single Pair Ethernet Cabling”, which took place as part of the “SPE Pioneer Summit” webinar series.
There are currently various communication systems in the industrial environment, such as Profinet, CAT 5e and 6a, Industrial Ethernet or Ethercat. However, Single Pair Ethernet has the potential to replace these technologies in many applications – thanks to data transmission at gigabit speeds and simultaneous power supply via just one pair of wires. This smart, flexible, cost- and space-saving solution enables real-time communication down to field level.
A basic condition for the use of SPE is that the correct technical infrastructure is available – from terminals and plug connections to cabling. To ease the transition for manufacturers and users, the same cable classifications have been defined for SPE as those already used for Profinet:
Type A: Solid wire wires for permanent installation
Type B: wires with stranded cores for flexible applications or vibration
Type C: wires with braided cores for highly dynamic applications (such as drag chains)
Type R: Torsion tested cables with braided conductors for robotic applications Drag chains and robotic cables differ mainly by their respective screening designed for bending or torsional load capacity.
In addition, different sheath materials are used for each cable type to meet specific applications. Type A and B cables are usually shielded with PVC. There are also plenty of halogen-free, food-safe, and oil- and chemical-resistant alternatives to choose from. Type C cables are available in PUR, PVC and Santoprene, and type R robot cables are also available in PUR and Santoprene.
| Jacket | Halogen-Free | Flame Retardancy | Low Smoke | Price | Oil Resistance | Repeated Bending | Abrasion Resistance | UL Flame Test Possibilities |
| PVC UL | no | medium-high | no | low-medium | low-high | medium | medium | VW1, FT1, FT4 |
| FRNC/LS0H/ LSZH |
yes | medium-high | yes | medium | low | low | low | VW1, FT1, FT4 |
| P.E | yes | no | yes | medium | low | low | low | no |
| PUR UL | yes | medium | medium | high | high | high | high | VW1, FT1, CFT |
| TPE (Santoprene) | no | medium | medium | high | high | high | high | VW1, FT1, CFT |
| TPE (Santoprene) | yes | no | medium | high | high | high | high | no |
Table 1: Properties of different sheath materials of SPE cables
For data transmission, Single Pair Ethernet offers various options in terms of speed and range:
10BASE-T1: data rate up to 10 Mbit/s, range up to 1,000 m
100BASE-T1: data rate up to 100 Mbit/s, range up to 40 m
1000BASE-T1: data rate up to 1 Gbit/s, range up to 40 m
MultiGigBASE-T1: data rate up to 2.5 / 5 / 10 Gbit/s, range up to 15 m
In the industrial environment, 10BASE-T1 and 1000BASE-T1 are currently the most important. The MultiGig technology, which is still under development, will open up more possibilities in the future. HELUKABEL has already added three different SPE cables for 10BASE-T1 and 1000BASE-T1 to its portfolio and the product range is constantly being expanded.
When comparing various existing industrial communication technologies with Single Pair Ethernet, many advantages emerge depending on the application. For example, 10BASE-T1 scores higher than Profibus PA with its significantly higher frequency range, which allows data transmission up to 320 times faster – fast enough for the transmission of videos, for example.
| Profibus PA / Foundation Fieldbus | SPE 10BASE-T1L | |
| Cross Section | AWG 18 solid or stranded / AWG 16 stranded | |
| Max. Distance | up to 1900 m non hazardous areas, up to 1000 m in hazardous areas (FISCO Power Supply to IEC 60079-11) | up to 1000 m (TI phy DP83TD510E > 2000 m Peer-to-Peer) |
| Impedance | 100 +- 20 ohms @ 31.25 kHz | 100 +- 15 ohms @ 20 MHz |
| Frequency Range | up to 39 kHz | up to 20MHz |
| Max. Data Rate | 31.25 kbit | 10 Mbit |
| Typical Connector | M12 a-coded 4 PIN IP67 | M8/M12 SPE IEC 63171-6 |
| 7/8 inch PI67 | ||
Table 2: Comparison of SPE 10BASE-T1 with Profibus PA
Compared to USB technology, both 1000BASE-T1 and MultiGigBASE-T1 offer significantly higher data rate and range, as well as greater power supply. 1000BASE-T1 is also preferred due to its smaller cable diameter and weight, lower copper requirements and tighter bend radii than cabling with Profibus DP, CAN or Industrial Ethernet.
| Profibus DP | SPE 1000BASE-T1 | SPE 1000BASE-T1 | SPE Advantage or Disadvantage | |
| Drag Chain Design | Drag Chain Design | Drag Chain Design | ||
| Cross Section | AWG 23/19 | AWG 26/19 | AWG 22/19 | |
| Data Rate | 12 Mbit | 1 Gbit | 83x more data rate | |
| Cable Diameter | 8.0mm | 4.9mm | 6.3mm | 21-38% reduced space |
| Max. Distance | 100m* | 40 m | disadvantage in length | |
| Power | no(hybrid) | PoDL up to 50W | power included | |
| Cable Weight | ~77kg/km | ~29kg/km | ~50kg/km | 35-60% reduced weight |
| Copper Fig. | 25kg/km | 16kg/km | 24kg/km | 4-36 % reduced copper |
| Bending Radius Chain | 96mm | 59mm | 76mm | 20-39% red bending radius |
*with high speed 12 Mbit
Table 3: Comparison of SPE 1000BASE-T1 with Profibus DP
More information can be found in the “Single Pair Ethernet (SPE) Cabling” webinar that HELUKABEL recently delivered as part of the SPE Industrial Partner Network's “SPE Pioneer Summit” series. HELUKABEL expert Horst Messerer gives a detailed presentation on the advantages of SPE technology compared to existing communication standards and explains which cables and connectors are already available on the market. The webinar can be accessed via this link SPE DIGITAL COFFEE BREAK: Single Pair Ethernet SPE cabling – YouTube can be viewed anytime for free.
Horst Messerer is Product Manager for Data, Network and Bus Technology.