Cable Requirements

What cable types are recommended for constructing measuring lines with RS-485 and CAN interfaces?

For constructing measurement networks with RS-485 and CAN interfaces, it is recommended to use twisted pairs with 120 Ohm impedance and about 5 ns/m signal propagation speed.

When choosing a cable it is also important to take into consideration its operating conditions. Generally, fixed measuring systems use cables with operating range from −40°C (outdoor version). When constructing small-scale measuring lines which will not operate in high interference conditions, it is possible to use unshielded cable; in the rest cases it is recommended to use screened cable. When choosing a cable, give preference to cables with stranded wire as conductor.


Table of recommended cables for constructing measuring lines

Number Of Pairs AWG Cable Description Outer Ø (mm) Op. Temp. (°С) Purpose
4 26 Shielded twisted pair SSTP (S/FTP), category 7 (600MHz), 4 couples (26AWG), multi-wire (patch), LSZH (305 m) 6.5 -20 to 70 for measuring lines up to 100 m
2 26 Flame retardant twisted pair high-speed transfer cable (bunched cable that resist fire propagation) 2×2×0.40 ВЭ-хл 8.8 -60 to 80 for measuring lines up to 100 m
2 24 Interface cable RS-422/485, 2×2×24 AWG SFTP , 120 Ohm, in PVC sheath for operating in wide temperature range 7.3 -45 to 70 for measuring lines up to 100 m
2 22 Teldor 9FY9F2V101 Interface cable RS-422/485, 2×2×22 AWG SFTP, 120 Ohms, multi-wire (stranded), SF/UTP, -35 С С- +70, FR-PVC, comparable to Belden 8132 6 -35 to 70 for measuring lines up to 200 m
2 22 Hyperline RS-SF2-O Interface cable RS-422/485, 2×2×22 AWG SFTP, multi-wire (stranded), (patch) 120 Ohm, in PVC sheath, cold-resistant 10.3 -55 to 70 for measuring lines up to 200 m
2 15 and 18 Trunk cable for networks DeviceNet, 2×18 AWG + 2×15 AWG S/STP (IEC 60332-1) in fire-resistant, low smoke halogenless compound sheath (FR-LSZH) 9822T18108 12 -20 to 75 for measuring lines up to 1,000 m