The Megger DET5/4D and DET5/4R are fully automatic, four terminal instruments built into a rugged, water resistant case giving protection for outdoor use. The instrument is suitable for the testing of earth electrodes and measuring earth resistivity.

Operation is started by pushing one of two buttons on the front panel; one for three terminal measurement and one for four terminal testing. All other functions of the instrument are completely automatic. The instrument checks for conditions that may cause an invalid reading during a test. The low service error and wide operating temperature range enable accurate results to be achieved in real on-site conditions