Using the standard method of a link cable in the top of the protective device can give learners potential connection problems, especially if boot lace ferrules have been used or if the link cable is a different size to the line conductor under test. This can result in false high resistance readings.

However, when a good connection is made a reliable result can be achieved.

One of the major problems with this method in a training centre or college is the damage often caused to expensive protective devices by learners over tightening or using the wrong screwdriver.

Using the R1R2 Link reduces the amount of damage to protective devices and speeds up the testing process for learners.

This can also be a huge benefit to training centres and colleges when time is of the essence during practical assessments.

When used with good quality screw heads the R1R2 Link will achieve the same results as a standard link cable into the top of the protective device without the need to disturb the connections.

However, even when the terminal screw head is damaged as shown here the R1R2 Link can still produce very accurate results.

The pictures above show an increase of only 0.01 Ohms with a badly damaged screw head.