Testing

Status
Not open for further replies.
T

taes

Member
Location
Texas
I need help on determining if their is a meter available to check the length of cable buried in the ground. Here is the situation, called out on a service call, owner has buried about 650 ft of aluminum cable to feed a service panel in a barn, 120/240v, 60 amps. There is no power when checked at the barn, but there is voltage at the source (breaker). The assumption is that the aluminum cable is broke into somewhere along the run. Does anyone know of an easy way to locate this break, thru a realtively inexpensive meter? Maybe some other suggestions.

Thanks
 
Re: Testing

I remember something from college classes about a technology called ?time domain reflectometry? (TDR). You send out a signal, and any abnormality in the cable (including a complete break) would send back a reflection wave. The time it takes for the round trip could be translated into a distance from the starting point. That class was long enough ago that there must be a cheap and easy testing device to do this job. But I?ve never been called upon to use one, so I don?t really know if they exist. That?s as far as I can help.
 
Re: Testing

I have a ground fault locator that I bought about 10 years ago. It will pinpoint the fault within a couple of inches. The company name is Progressive Electronics Inc. out of Mesa, Arizona. It is called a Model 2003 Pulser Ground Fault Locator. I got it from my local electrical wholsaler. It works great but I can't remember what it cost and I don't know if they are still in business. Good Luck!
Mike
 
Re: Testing

One of the things I am able to do these days is network - working with other ECs who have what I don't have. If you are friendly or talk to the supply house, they may be able to refer you to someone who has this equipment. It is a great way to be active with 'our' community of electricians.
If that does not work, then places like Graingers or Graymark have the equipment that you can purchase or there are some rental places also.
Good Luck!
 
Re: Testing

Pierre makes a good point. I recently was in the same situation and asked a fellow contractor (who I know had Ideal ground fault locating and tracing equipment) to assist me in finding the fault. Doesn't make sense for me to purchase the equipment, which is rather expensive, for infrequent use.
 
Re: Testing

I would try to rent what i need.Bringing in another company might cost you buisness in the future.How much does the instument cost? might be nice to own it.I assume it would sent out a radio wave and you follow it with a receiver
 
Re: Testing

Jim:

The firm I work for has expertise in many aspects of the electrical field that most electric contractors do not indulge in. We have made a go of it with my love of toys and employing men with a wiliness to learn. My point is that sometimes subbing is wise move.

The cost of renting equipment, getting up to speed with the equipment at the customer expense, is IMO not wise.

Maybe that is a selfish point of view as I have $100,000.00 of equipment to pay for. But a majority of my work is for electrical contractors. I do not so go after their customers, if their customers call me, I inform them I work for their contractor, I call the contractor and inform him and take direction from him, sometimes they tell me to go direct other times I work for the contractor. Most times the customer is happy with either arrangement just so the work is completed.

We will also loan some test equipment to our regular custoemrs, if they are in a pinch.

But getting to be an expert in a field such as cable fault locating is a good idea, if one buys the right tools and invest in the training. There is a contractor in our area that only does cable and fault locating, he keeps 4 men going full time locating cables Miss Utility does not locate and fault finding.

One thing I have found is some test equipment sits for weeks or months then all of a sudden I need 6 of them.

We use the Progessive Electronics fault locator and have been very happy with it.
 
Re: Testing

Brian, you have hit on a big point here,
invest in the training.
Click to expand...
many pieces of equipment or testers can be used by anyone right out of the box.

Other equipment, testers, analyzers, imaging equipment, etc... can not.

Jim, if a contractor with out this training refuses to contract with someone who can offer this service, they will most certainly loose the customer.

Roger

[ December 12, 2003, 09:20 PM: Message edited by: roger ]
 
Re: Testing

The experience that Brian and Roger bring to the table proves a point. That education and training are vital in this industry and to maintain that training. Also it is nearly impossible to know it all. The longer you are in business, the more other people/businesses you become friendly with. This is where 'networking' really PAYS big dividends.

Lets say I have developed a business relationship with Brian. I have multiple jobs running, but I am a small shop. A customer calls with a problem and I determine there is a fault somewhere, but I do not have the equipment or expertice to find it quickly (I also do not have much time, as I am busy on other work). I hire Brian, and while he is locating the fault, I am making a percentage of what he is charging and still completing my other work on schedule (YEAH RIGHT!!). So not only is Brian helping, but I look good in the process of making more money. A WIN WIN WIN situation. Win for Brian, win for the customer, and a win for me :D .


Here is another plus resulting from networking (do you think I like networking ;) )
I like not having too many employees - that is my personal way, I am not knocking anyone with larger shops.
I can do more work I like to do and hire the specialists who are good at what they do. I always get calls from existing and sometimes other customers who have a problem. The situation usually occurs when I have no free time, so I call another electrical contractor with a larger shop or an expert like Brian. It is a big stress reliever to have that option.

This past Thanksgiving night I received a 3am call :mad: from a regular customer that had a fire raging in their apartment building. They needed an electrical contractor to be able to be ready to hook up a temp boiler and rewire the burned out areas, as well as turn the power back on to the building which the POCO had shut down. I am too busy and I do not want work like this anymore, so I called a friend who owns a larger shop and after his initial reaction of being pissed at 3:30 am he was delighted to occupy some of his men for the next couple of months.

Pierre
 
Re: Testing

..Bringing in another company might cost you buisness in the future.How much does the instument cost?

Really doesn't matter how much it costs if you are only going to use it once, you're losing money.

Also, the attitude that you can't work in harmony with another contractor is a poor one that I see all too frequently. Sure, it would be ideal if we were all qualified and equipped to do everything this industry required but that's not the case. Yet, I've known contractors who would never turn down a job no matter how ill equipped they were to handle it. I once knew a contractor that showed up to pull a 500 foot set of 500 MCM's with only himself and a couple of lengths of 1-1/4 galvanized conduit and some concrete blocks to support the reels! Somehow he coerced some of the other trades on the job to help him. :roll: So, they might muddle through but did they make any money or do the customer justice?
 
Re: Testing

brian john,
you hit on a good point------ test equipment sits and sits....... then you don't have enough. and as it "sits and sits" the batteries go bad and the dates run out on the "calibration requirements". we do infrared testing and have over $100,000. invested in test equipment - we do not advertise it, but the word is out and we get more and more calls from other contractors requesting our help. when we arrive on the job the customer doesn't know that we don't work for his contractor and if the customer calls us we always refer him back through the original contractor. i like it better that way - i bill the original contractor. we have three power analyzers with different sets of c.t's all the way to 4000 amps--that gets expensive! but it seams like it's either too much or not enough-feast of famin!
 
Re: Testing

we use the inframetrics infrared units - i have the 577L unit. it's old and heavy but very,very sensitive! can't get that high sensativity out of the new machines.
data loggers i have two metrosonics pa-7, had them for years, also have three dranitz units.
i like the metrosonics above the others. i had to rent some additional units to monitor hospital emergency services for a month and they sent me RPM units - what a mess. i spent more time on the phone with their manufacturer programing and trying to get them to download. then i didn't have faith in their data and used the metrosonics to double check them. i rented five of these and they were all the same model, but they would not program nor download the same. maybe because they were rental units and people had installed programs in their memory? i hate it when they tell you "forget what the instruction manual says"!!!!!!!!!!!!!!!
 
Re: Testing

The tool that I use for this purpose is called a Short Stop Cable Fault Finder. You can view this at www.starkelectronic.com

They have it listed for $329.00, though I paid much less than that for mine.

Very simple to use, very versatile tool.
 
Status
Not open for further replies.
Top