10. Earth resistance measurement ..................................................................................................49
10.1. Connection terminals ............................................................................................................................49
10.2. Touch voltage limit ................................................................................................................................49
10.3. Making a measurement – Two pole resistance measurement ............................................................49
10.4. Making a measurement – Three terminal resistance measurement ..................................................50
10.5. Making a measurement – Three terminal resistance measurement using ART ................................51
10.6. Two-clamp stake-less measurement (MFT1835 and MFT1845+ Only) ................................................52
11. Setup options .............................................................................................................................53
12. Warning messages ..................................................................................................................... 54
12.1. Startup warnings ...................................................................................................................................54
12.2. Battery ....................................................................................................................................................54
12.3. Battery charger ...................................................................................................................................... 54
12.4. Fuse warning .........................................................................................................................................54
12.5. Invalid rotary switch setting .................................................................................................................54
12.6. Continuity test .......................................................................................................................................54
12.7. Insulation test ........................................................................................................................................54
12.8. RCD test (or GFCI) ..................................................................................................................................54
12.9. RCD range selection errors....................................................................................................................55
12.10. Loop test ..............................................................................................................................................55
12.11. Earth test .............................................................................................................................................55
12.12. Test will not start ................................................................................................................................. 55
13. Appendix A – Sending, Storing, Deleting and Recalling Test Results
(MFT1835 and MFT1845+) ..........................................................................................................56
14. Appedix B – Downloading data via Bluetooth
®
(MFT1835 and MFT1845+) ..........................................................................................................60
15. Appendix C – Installation category definitions ........................................................................61
16. Appendix D – Safe working practice ........................................................................................61
17. Appendix E – Cleaning and maintenance .................................................................................61
18. Appendix F – Earth resistance testing – Basic principles .........................................................62
18.1. F.1 Principle of operation (three-terminal resistance measurement) ................................................ 62
18.2. F.2 Principle of operation (three-terminal resistance measurement using ART) ..............................63
18.3. F.3 Principle of operation (two-clamp stake-less resistance measurement) ......................................63
www.megger.com
MFT1800 series
6