Maybe a dumb question about meter leads?

[PurpleSquish]

Hello folks! Never been here before but I have a question that's been bugging me for a while. I recently got a job at a chemical plant that's been around for quite a while. Long story short is there hasn't always been a norm for electrical diagrams. It's an absolute rat's nest of pipes and conduit everywhere and we normally deal with instruments/solenoids and the like controlled or transmitting to PLC's. I've always wondered when we don't know where something connects in the field (which can be quite frequent) why we don't just get like 1/8 mile of wire and ohm it out with a meter. Is there something wrong with my thinking? Thanks for any insight!

 

[OkiePC]

I've used up to 100' of wire like that when there wasn't a solid ground reference at both ends to use as a reference. I don't know about 1/8 mile though!
Seems like there should be a better way.

 

[danw]

Me, too. I've got about 95 feet of 14-3 former 100 foot extension cord (that got cut at one point) with insulated alligator clips on all the conductors, but there's a limit to dragging cable around and dealing with the Safety Officer that wants the cord crossing the walkway to be taped down and a saw horse with a sign put over it so no one trips over it.

 

[robertmee]

Use a toner/wand

 

[Tom Jenkins]

Old timers would use a pair of telephone handsets with batteries strapped on for power with one known wire connected between them. Alligator clips would be connected to the end of one wire and the other end, often even in another building, connected to each wire in the conduit in succession. When a match was made the phone would ring. This process was referred to as ringing out the wiring.

 

[Scottryan03]

Old timers would use a pair of telephone handsets with batteries strapped on for power with one known wire connected between them. Alligator clips would be connected to the end of one wire and the other end, often even in another building, connected to each wire in the conduit in succession. When a match was made the phone would ring. This process was referred to as ringing out the wiring.

I always wondered where 'ringing out' came from. Awesome, thanks

 

[RClem]

I've been known use a 500' roll of wire as an extension lead in those circumstances.

 

[Lare]

Old timers would use a pair of telephone handsets with batteries strapped on for power with one known wire connected between them. Alligator clips would be connected to the end of one wire and the other end, often even in another building, connected to each wire in the conduit in succession. When a match was made the phone would ring. This process was referred to as ringing out the wiring.

Done that several days no more than some 20 years ago with older coworker. We did cable ploughing and all wire joints needed to check functionality afterwards between several kilometers. Handsets were probably from somewhere 60's or 70's. It needed only three wires. Nice design and it still worked well. It had earmuffs and mic and we could speak each other when tested other wires.

 

[parky]

most companies have radios for maintenance, requires two people but just get one at each end then short each cable in turn to either ground or to another designated cable did this for years, until I built myself a 16 wire system with led's connect the transmitter to one end & the reciever to the other, normally only used one or two channels each had a different flash rate I used cmos digital ic's to generate the pulses did not use it much as there was normally one other engineer availlable to do the testing.