A company manufacturing overhead transmission and distribution power line equipment has used a Cropico high performance microhmmeter for accurate resistance measurement during an anti-corrosion product testing programme.
Overhead Line Fittings (UK) works with the National Grid, power distribution network operators and their contractors to provide bespoke insulators, fittings and conductor accessories used in the installation and maintenance of overhead power cables.
As part of the services provided to customers, the company operates an in-house test facility at its head quarters in Atherstone, Warwickshire.
There it has been testing bi-metallic joints to assess how its oxide-inhibiting compound can reduce the rate of corrosion between electrical connections.
This is a major problem which costs utilities millions of pounds a year in maintenance and repair costs and can cause delays to essential services like the railways when power distribution lines fail.
OLF's testing involved a heat cycle process which utilised a Cropico D05000 microhmmeter for the measurement of resistance levels.
A current of 700 Amps was passed through a bi-metallic joint in a cycle of one hour energised and 40 minutes de-energised. Humidity levels averaged 60% during the testing, which was conducted on both compound treated and non-treated joints continuously for 96 hours.
Resistance readings were taken automatically at the rate of two per second showing that levels rose as the galvanic corrosion started to attack the joint.
The testing confirmed that an oxide-inhibiting compound can have a positive impact on the electrical performance of the type of bi-metallic joints used on transmission and distribution power liners.
Carl Ford, general manager at OLF, said the high performance capabilities of the D05000 had led to the decision to order another unit for the company's operation in China for a similar test and measurement programme.
He added: "The D05000 is a very good instrument, offering superb performance, reliability and accuracy. It's fulfilled all expectations and has impressed within the demands of the testing environment."
The Cropico D05000 microhmmeter enables highly accurate low resistance measurement to be undertaken to ensure products meet relevant technical performance standards and specifications.
Programmable current levels and the selection of different test speed settings give the D05000 tester the flexibility to accurately measure the resistance values of different cable products. These include single end and plain soft wires through to bunched, stranded and large diameter rope type conductors.
Accurate and reliable in-line cable resistance measurements taken in this way enable cable manufacturers to maintain optimum operating efficiencies in terms of copper raw material use.
The D05000 forms part of a comprehensive range of precision measurement instruments available from Cropico, part of the Seaward Group.
Cropico
0191 586 3511
[email protected]
www.cropico.com
