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#204129 - 11/14/11 08:26 PM circuit mapping?
crselectric Offline

Registered: 09/24/06
Posts: 134
Loc: albany, ca
Any tricks or tips on making circuit map/list for old victorian type house, mostly K&T, some new kitchen circuits, but has three sub-panels that supply main areas of house, difficult to hunt and peck out circuits, anyone familiar with a Extech ct-40 tracer, it has 16 leads and common then test unit that will say which breaker lead at the recept.s? tried the walkie talkie route but too confusing with homeowner

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#204130 - 11/14/11 09:00 PM Re: circuit mapping? [Re: crselectric]
KJay Offline

Registered: 11/27/07
Posts: 763
Loc: MA, USA
I donít have any experience with the Extech CT40, but for the price, I donít think you could go wrong.
Iíve had my eye on one of the Tasco CMT42S circuit mappers for a few years now, but that kind of price for something Iíve never used before just seems to always stop me cold.

Tasco Circuit Mapper

#204141 - 11/15/11 11:44 PM Re: circuit mapping? [Re: crselectric]
Niko Offline

Registered: 08/17/06
Posts: 358
Loc: Campbell, CA
i use bunch of night lights and lot of back & forth from panel to the house.

i have seen the TASCO mapper in action. it is amazing.

Edited by Niko (11/15/11 11:44 PM)
Edit Reason: spelling
Be kind to your neighbor, he knows where you live

#204142 - 11/16/11 01:03 AM Re: circuit mapping? [Re: crselectric]
gfretwell Offline


Registered: 07/20/04
Posts: 9024
Loc: Estero,Fl,usa
You can use a radio plugged into the tested outlet (use an edison to 1-15 adapter in lighting outlets) if the customer can stand the noise.
Greg Fretwell

#204143 - 11/16/11 01:13 PM Re: circuit mapping? [Re: gfretwell]
KJay Offline

Registered: 11/27/07
Posts: 763
Loc: MA, USA
Sometimes I will just shut off all but one circuit and do a walkthrough of the house with a receptacle tester and a notepad making notations as to what lights and receptacles are on that circuit. This is pretty time consuming for one person though, especially with a building like in the OPís case. Thatís one reason I would like to try out one of those circuit mappers next time this type of situation comes up.

I have one of those TestUm Lanscaper network cable mappers with 8-remotes and a bunch of different adapter cords, but I never actually thought about trying it on deenergized line voltage circuits before.
I know if I unplug lamps and small appliances from the receptacles and turn off all the wall switches for ceiling lights, I can use a toner/probe to trace a deenergized circuit through the building this way, so maybe Iíll try the network mapper around my house and see how it works out.

#204145 - 11/16/11 01:51 PM Re: circuit mapping? [Re: crselectric]
Tesla Offline

Registered: 06/16/04
Posts: 1280
Loc: Sacramento, CA
I've long owned a TASCO 42S...

I got the convention discount when it was first introduced.

If you have to rebuild panel schedules in a hurry it's the way to go.

It also permits you to figure things out while a business is on going.

A reduced circuit count device is also sold for residential situations.

#204146 - 11/16/11 02:38 PM Re: circuit mapping? [Re: crselectric]
HotLine1 Offline


Registered: 04/03/02
Posts: 6791
Loc: Brick, NJ USA
If you can find one of those 'button' type bulb flashers, they work great in edison base light fixtures....

Unscrew bulb, insert button in socket base, re-install bulb.

Use a 100 watt bulb, and amp clamp for a close to 1 amp pulse...that's the circuit.

Ringing out a new house, use a 'temp' socket at the lighting locations.

Dig around and find an old adaptor socket that plugs into a receptacle.....proceed as above.

Also, used the radio. In comm jobs, I had a 120 volt claxon horn! Not reccomended for an occupied resi job though.

#204179 - 11/18/11 06:41 AM Re: circuit mapping? [Re: crselectric]
harold endean Offline

Registered: 02/16/02
Posts: 2248
Loc: Boonton, NJ
I use to have a Paser tracer. ( I believe that was how it was spelled.) Then Amprobe bought them out. There were 2 types of tracers. 1 for live circuits and 1 for dead circuits. We used them all the time.

#204181 - 11/18/11 07:40 AM Re: circuit mapping? [Re: HotLine1]
KJay Offline

Registered: 11/27/07
Posts: 763
Loc: MA, USA
Iíve heard about the flasher trick for years, but have never actually tried it myself. I noticed that Cooper says their BP1008 flasher button has a 65-85 per minute flash rate. Is that something that would work with a digital amp clamp or is it better suited to an analog type clamp?
My thinking is that it might be too fast for a digital clamp meter display to stabilize, but might be easier to see the needle bounce on an analog meter, although maybe not.

#204210 - 11/21/11 03:20 AM Re: circuit mapping? [Re: crselectric]
knowledge Offline
New Member

Registered: 08/28/11
Posts: 3
Loc: mass
well is that ^ the best convenient way to trace them? or to tool is the way to go


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