Forkinhades Posted June 3, 2017 Share Posted June 3, 2017 PerfectSent from my SM-G935F using Thailand Forum - Thaivisa mobile app Link to comment Share on other sites More sharing options...
RichCor Posted June 3, 2017 Share Posted June 3, 2017 Generally, you measure coaxial cable for continuity (to verify no open breaks, no shorts), then measure the resistance of the Outer Shield, then inner core for integrity. Measuring Outer and Inner combined confuses things a bit -- but if the cable is still in or near original spec then the meter reading should reflect (roughly) the resistance of the actual calculated length. You'll get a different result depending on the makeup of the transmission medium. Solid Copper will have a lower resistance than Copper Coated Steel. I only check for shorts and opens, then plug n pray. Only do the other measurements when tracking a fault condition. Link to comment Share on other sites More sharing options...
janclaes47 Posted June 3, 2017 Author Share Posted June 3, 2017 1 minute ago, RichCor said: Generally, you measure coaxial cable for continuity (to verify no open breaks, no shorts), then measure the resistance of the Outer Shield, then inner core for integrity. Measuring Outer and Inner combined confuses things a bit -- but if the cable is still in or near original spec then the meter reading should reflect (roughly) the resistance of the actual calculated length. You'll get a different result depending on the makeup of the transmission medium. Solid Copper will have a lower resistance than Copper Coated Steel. I only check for shorts and opens, then plug n pray. Only do the other measurements when tracking a fault condition. How do you measure resistance from core or outer shield on a 40 meter long cable? Link to comment Share on other sites More sharing options...
Crossy Posted June 3, 2017 Share Posted June 3, 2017 8 minutes ago, janclaes47 said: How do you measure resistance from core or outer shield on a 40 meter long cable? A long wander lead. But verifying continuity with a short at the far end and open without the short should do the trick. Link to comment Share on other sites More sharing options...
Forkinhades Posted June 3, 2017 Share Posted June 3, 2017 To measure end to end resistance, you need to put your test leads on each end of the cable. If you run a tempoary wire between the 2 positions, take the measurement of the tempoary wire and note it down. You can now measure the resistance of the inner core by using the temporary wire. You then subtract obe from the other, that will give your ohmic reading of the inner core.You have already done this by shorting tbe braid and the inner core. Unfortunately we do not know the resistance of the braid. In order to subtract it from the measurement.The braid will be higher thsn the inner core. Lets just say its 8 ohms in this case. Which makes your inner core 3 ohms. Which is fine. Thr fact that the inner core and braid are clear, means your cable will be acceptable for the task.You are worrying too much about nithing really.Sent from my SM-G935F using Thailand Forum - Thaivisa mobile app Link to comment Share on other sites More sharing options...
Forkinhades Posted June 3, 2017 Share Posted June 3, 2017 A long wander lead.Simple answer (like it), was posting whislt you gave your answer.Sent from my SM-G935F using Thailand Forum - Thaivisa mobile app Link to comment Share on other sites More sharing options...
Crossy Posted June 3, 2017 Share Posted June 3, 2017 Just now, Forkinhades said: Simple answer (like it), was posting whislt you gave your answer. I'm in a minimalist mood today Link to comment Share on other sites More sharing options...
Forkinhades Posted June 3, 2017 Share Posted June 3, 2017 Very civil. [emoji16]Sent from my SM-G935F using Thailand Forum - Thaivisa mobile app Link to comment Share on other sites More sharing options...
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