Electrical / Circuit Tester/ Tracer

...the HO/neighbor's kid

less expensive than:

Circuit Mapper Breaker Identification System - 42 Circuit

http://www.mitchellinstrument.com/circuit-mapping-system.html

That widget would do the trick.

Label the wires with letters, tie them together in pairs, go to roof and check continuity, mark the wires with numbers, and tie the continuous pairs together, go back downstairs and untwist the wires and switch the wires that were tied together with other wires, and test for continuity, now go back to the roof and repeat process....Draw diagram with letters on one side and numbers on the other side and as you determine each wire draw line from letter to corresponding number...switch numbers with proper letter to mark wires on roof...

I like the idea, but not sure if the measurement of 1 or 2 volts differential is reliable working with dirty wire connections in the field....might be worth a try...

Been there, done that; it works great, even the single cell circuit if you clean or scratch the copper. G.A.

I like JNB's idea, but he beat me to it, solder some wires to batteries connected in series. Or hire a kid to help.

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Thank you, I never thought about different voltages for different wires. I bet Mac Guyver uses this method all the time !

Ahh that's what happens when you respond without reading all of the other posts... I see that this method of testing has already been mentioned.

GA to Randall, and I can attest to the method as being very efficient.

Yes. -- JHF

The resistor method is a good way, but you don't really need them if your wires are long and your meter has an accurate low ohms scale.

Twist one end in pairs. Go to other end and twist this end again in pairs except two.

Connect meter to one of the non-twisted wires and read the ohms to each twisted set of wires on that end. The readings will increase as the length of the wires goes up. Using a set of alligator clips helps the reliability of your readings. Write down the readings and mark them in order of readings

No resistors and no batteries! Just basic series resistance theory.

This looks as though it might work with a lot of messing about, but, at the moment: I'm a bit confused.

When you get to the top you can easily sort out which pairs are shorted at the other end, and so you can easily short one of each pair to the next pair to make one continuous conductor. But after you make your first reading (the resistance of one pair from top to bottom and back) you can predict exactly what all the other readings will be, and, therefore the readings are not really telling you anything.

And you still can't correlate the pairs at the top with the pairs at the bottom.

I can't see how that would work...Perhaps you can explain it a bit more thoroughly.

The different applied Vs and Rs to each conductor is a great way of giving each a signature.

Alternatively have different music sources connected to each and sort them out by melody with a speaker probing the other end.

Non invasive cable tracers work real well too. Get a few with different tones.

Rent an apprentice........

I have a great idea that your client will love. Take the swamp cooler off the roof, cover the hole and patch it. Then install a new style window unit, such as the Bonaire unit (Home Depot sells two different sizes).

Your client will love how well the unit works and they won't have calcium marks dripping down the roof.

And, you don't have to worry about which wire to hook up.

In response: I appreciate all of the good answers, they are very helpful.

In reply to the last post: Yes, I have installed the Bon Aire Durango, Quality Australian Engineering. It would be nice if that company would export their down draft unit with the enviro wing here.

Methods to reduce or eliminate scale dripping on clients roof. All evap coolers have an overflow drain, the purpose of the drain is to remove water from the reservoir basin in the event the make up water supply metering valve malfunctions. Some down / side / up draft coolers are constructed from separate individual pieces, such as where the reservoir basin mounting flange is lower than the blower assembly mount flange, if the metering valve malfunctions, water can be drawn into the plenum venturi through capillary action or intake pressure while the blower is operating ( Trade wind TC 451/471/ for example) . With respect to the Trade wind, it is necessary to adjust the overflow drain riser so there is a 1" gap between the top of the overflow drain opening and lower than the basin flange in a horizontal plane.

Here in California we use drip watering systems, these water distribution systems use black polyvinyl tubing and 1/2" compression fit connectors ( sold at home depot etc. ) . Simple fix here: you will need a hose adapter fitting, a 90* fitting and a length of tubing as required for your application, Screw the hose adapter to the threaded portion of the overflow drain underneath the cooler ( use PTFE paste) , then a short length of tubing, then the 90* , then a length of tubing as required to the roof gutter/drain ( easy weezie) . I think this looks more professional than using a cutoff garden hose.