1RInstrument Transformer WiringTroubleshooting GuideThree Phase MetersRevision 0, Initial Issue, April 26, 1993CONTENTSI. How to Use This GuideII. Common Problems for 3-Wire and 4-Wire SystemsIII. 3-Wire System TroubleshootingIV. 4-Wire System TroubleshootingV. Actual Field ExamplesI. HOW TO USE THIS GUIDE1. Symptoms listed are "ideal"; some judgment must be exercised. For example, if KW reading is 25but you know that it should be about 300 KW, go to where this guide lists "KW=0" as one of thesymptoms.2. Section II "Common Problems for 3-Wire and 4-Wire Systems" addresses symptoms and possiblecauses which occur regardless of system type; this section should be checked first. If the symptomsare more complicated, proceed to Section III for 3-wire systems or Section IV for 4-wire systems asappropriate.3. Always assume that the problem is in the wiring to the Circuit Monitor; do not assume a defectiveCircuit Monitor. Experience has shown that this is almost always a good assumption.4. This guide addresses mostly only a single wiring problem at a time. It is nearly impossible toaddress all combinations of multiple wiring mistakes or other problems which can occur such asblown PT fuses, missing PT neutral ground connection, etc.5. When calling in for troubleshooting assistance, it is imperative that all instantaneous Circuit Monitorreadings be provided. Specifically, this includes line-to-line voltages, line-to-neutral voltages, phasecurrents, phase power factors, KW, KVAR, and KVA. Printouts of logged readings or waveformcapture data, if available, can be extremely useful as well.What is "Normal"? See the next page.