Service manual

Contents
1 Introduction
6
1.1 Purpose
6
1.2 Product Overview
6
1.3 Safety
6
1.4 Electrostatic Discharge (ESD)
6
1.5 Tools Required
9
1.6 Electrical Installation in General
10
1.7 Exploded Views – H Frame Size
11
1.8 Exploded Views - I Frame Size
14
1.9 Ratings Tables
17
1.9.1 Short Circuit and Over-current Trips 17
1.9.2 DC Voltage Levels 17
2 Frequency Converter Control
18
2.1 Introduction
18
2.2 Status Messages
18
2.3 Frequency Converter Inputs and Outputs
18
2.3.1 Input signals 18
2.3.2 Output Signals 19
2.4 Service Functions
19
2.5 Control Terminals
19
2.6 Control Terminal Functions
20
2.7 Earthing Shielded Cables
22
3 Internal Frequency Converter Operation
23
3.1 General
23
3.2 Description of Operation
23
3.2.1 Logic section 23
3.2.2 Logic to Power Interface 24
3.2.3 Power Section 24
3.3 Sequence of Operation
24
3.3.1 Rectifier Section 24
3.3.2 Intermediate Section 26
3.3.3 Inverter Section 28
3.3.4 Fan Speed Control 30
4 Troubleshooting
31
4.1 Troubleshooting Tips
31
4.2 Exterior Fault Troubleshooting
31
4.3 Fault Symptom Troubleshooting
31
Contents
VLT
®
HVAC Basic Drive Service Manual
MG90X202 - VLT
®
is a registered Danfoss trademark 1