Service manual

4.4 Visual Inspection
32
4.5 Fault Symptoms
33
4.5.1 No Display 33
4.5.2 Intermittent Display 33
4.5.3 Display (Line2) Flashing 33
4.5.4 WRONG or WRONG LCP Displayed 33
4.5.5 Motor Will Not Run 33
4.5.6 Incorrect Motor Operation 34
4.6 Warnings and Alarms
34
4.6.1 Alarms 34
4.6.2 Warnings 35
4.6.3 Warning And Alarm Messages 35
4.7 After Repair Tests
39
5 Frequency Converter and Motor Applications
41
5.1 Torque Limit, Current Limit, and Unstable Motor Operation
41
5.1.1 Overvoltage Trips 41
5.1.2 Mains Phase Loss Trips 41
5.1.3 Control Logic Problems 42
5.1.4 Programming Problems 42
5.1.5 Motor/Load Problems 43
5.2 Internal Frequency Converter Problems
43
5.2.1 Current Sensor Faults 43
5.2.2 Signal and Power Wiring Considerations for Electromagnetic Compatibility 43
5.2.3 Effect of EMI 43
5.2.4 Sources of EMI 44
5.2.5 EMI Propagation 44
5.2.6 Preventive Measures 45
6 Test Procedures
46
6.1 Non-repairable Units
46
6.2 Introduction
48
6.3 Static Test Procedures
48
6.3.1 Pre-requisite 48
6.3.2 Rectifier Circuit Test 49
6.3.3 Inverter Section Tests 49
6.3.4 Intermediate Section Tests 50
6.3.5 Location of UDC Terminals 50
6.4 Dynamic Test Procedures
52
6.4.1 No Display Test (Display is Optional) 53
6.4.2 Input Voltage Test 53
Contents
VLT
®
HVAC Basic Drive Service Manual
2 MG90X202 - VLT
®
is a registered Danfoss trademark