in reply to: Fieldbus cable Specification posted by Sushil Lanjekar on 02 October 2003 at 12:09:33.
I need some confirmations / clarifications on Fieldbus cables for the project executed in Muscat, Oman. The field cables are purchased by the client (M/s. Galfar Engg. & Cont.) and that he wants us to vet the technical specs (primarily electrical characteristics). I went through all documents regarding FF cables, everywhere it is mentioned that the recommended cable is Type A cable which is IEC 61158-2 standard. The cable which the customer has proposed is of BS 5308 Type 2 cable. The following table indicates the comparison between the two standards,
Description
Specification w.r.t BS 5308
Specification w.r.t IEC 61158-2
Cable Size
2P x 1 Sq.mm
2P x 18AWG
Cable Type
Twisted pair, Indv. & Overall screened
Twisted pair, shielded
Electrical Characteristics
Conductor DC Resistance
18.40 Ohm / km
22.3 Ohm / km
Mutual Capacitance
115pF/mtr = 115nF/km
Max. 60nF/km
L/R ratio
25microH/ohm
Inductance
0.65mH/km
Request you kindly confirm whether can we go ahead with any type of cable which suits the requirement of Fieldbus