How do I use the earth bond calculator on PrimeTest 3xx series?

By default, test sequences within the PrimeTest 3XX portable appliance testers will have a pre-programmed pass limit. However the reality is that items with differing conductor thicknesses and lengths will have a pass limit potentially greater than the default limit.

In accordance with the IEE Code of Practice for In-service Inspection and Testing of Electrical Equipment, the PrimeTest 3XX can calculate the correct pass limits for a given cross sectional area and length of cable.

In order to configure the tester to be able to perform this operation firstly the user must enter the Test Options Screen from the main menu


The following screen will appear, ensure the tester is set to Failure Menu within the On Test Failure section.


When performing a test where the nominal resistance is greater than the pre-defined pass limit the tester will fail the equipment, however the following menu will appear.


By selecting Restart Test the user can now go back to the beginning of the Earth Bond Test, however this time they will notice that the F3 key on the tester now has an active function calc.


Once this button is pressed the following screen appears allowing the user to input the correct cross sectional area of the conductors and the length of the lead.


By pressing the OK button the pass value is now updated and the test can be performed.

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