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Advice on testers, 7620 volts

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waross

Electrical
Jan 7, 2006
27,786
Hello friends:
I will appreciate some suggestions on testers, specifically a reliable tester to indicate the presence of voltage on a distribution system running 7620 volts to ground.
Recently there was a tragedy at the little power system out on the island in Central America. There was a mixup and the wrong cut-out was pulled. The lead lineman lost an arm above the elbow and a leg above the knee.
This is a very small system. The field crew who maintain the lines and read the meters consists of two linemen and 1 to 3 helpers. The general manager often assists the crew himself on new transformer installations.
The manager has asked for my help in selecting some test equipment to prevent any incidents in the future. I supply a lot of the technical advice to the manager and an engineer in Florida has also given a lot of his time and a lot of good advice over the years. When they had a problem they would call me and I would be on the next plane out to the island. I have relocated to Canada and can usually only respond by phone or e-mail. They have recently called me down from Canada to resolve a metering issue and I am in Central America now.
The point, however, is that there is not a lot of immediate technical assistance available to the people here.
With this in mind, we are looking for recomendations for a light rugged dependable tester for 7620 volts.
For the most part there are no roads. Often the crew will travel first by small boat as close to the problem as possible and then walk in carrying their tools. At the far end of the system they have about 2 or 3 miles of road and an old line truck. It is still a long ride in an open boat to get to the truck.
We are looking for a tester that can be used and tested by semi trained workers.
I am sure that it will be splashed with salt water from time to time.
It should be light and easy to carry or it may be left behind in the boat.
The manager is also going to purchase 600 volt testers for the boys for secondary work. I am familiar with a couple of models of Fluke capacitive testors.
Notwithstanding, any suggestions or anecdotes are welcome.
Thanks to everyone
Respectfully
 
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hastings 6701 or 6701-1 if you want to be able to test underground too should do the trick. Sorry to hear about the accident - always a tragedy
 
Waross, we use (and have been using for many years now) a device called a Modiewark to detect voltages after de-energisation and prior to applying portable earths (grounds) to equipment. It is a multi-voltage range device, specifiable in a number of different models and can either be handheld or applied to a live-line operating stick for higher voltages. It can be used for low voltage detection, up spouts of metalclad switchgear in substation yards or on open overhead lines.

The units are lightweight and come in a small waterproof suitcase. We have hundreds of these units in service and have had very little trouble with their operation. Basically you test the device with a tester immediately prior to using it, then use it on your job, then test it again immediately after use to ensure it was working properly through the whole event.

The following web address gives the specs of the models, as well as a how to use safety guide for the units.


The only maloperation of the device that we have had has been due to the incorrect use by the operator.

They are made in Australia, but assume that they can be sourced overseas. Also if you google "modiewark" you will find places that sell live line sticks with attachments dedicated to Modiewarks.

Good luck with it.

ausphil.
 
Thanks for the information apowerengr and ausphil.
Respectfully
Bill

 
My salutes and respects to all in Central America and other countries in similar situations. With the lack of main technical support, working under extreme conditions, they must be considered brave men. A big plus to you waross for helping them.
Regards
 
A presentation on this subject can be found at

It appears that the Modiewark tester is also sold as the 4244 by Salisbury

I would recommend caution and training on the use of capacitive or proximity testers at low voltages. The advantages and disadvantages of these testers is outlined in the presentation.

For testing for the absence of voltage at less than 600 volts I would recommend a voltage only tester such as the Vol-Con by Ideal, the safety volt meter 110A made by Tegam or one of the voltage only testers by Fluke.
The company I work for does not allow mult-meters to be used to test for the absence of voltage because the multimeter is often put on the wrong setting.
 
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