Learning outcomes
- Explain the key principles of vsd principles, selection and installation.
- Carry out a structured practical check or configuration task.
- Recognise common faults, risks and evidence needed for diagnosis.
Module 5 · Lesson 1
VSD principles, selection and installation
Understand rectifier, DC bus, inverter, motor compatibility, harmonics, EMC and environmental requirements.
Before you begin
VSD manual, motor data, load profile and installation drawing.
Safety: Use site procedures, approved test equipment and competent supervision. Never bypass a protection or interlock without formal control.
Step-by-step learning
- Match drive current and overload rating to the motor and duty.
- Confirm supply, enclosure, cooling, cable length and motor insulation suitability.
- Plan input protection, isolation, earthing and EMC measures.
- Document every selected option and accessory.
Ian's practical tips:
- Select a drive by current and duty, not just motor kilowatts.
- Long motor cables may require output reactors or filters.
Fault-finding questions
- What should be happening, and what evidence proves it?
- Where is the last known correct signal, voltage, state or process condition?
- What changed immediately before the fault?
- Can the system be divided into smaller testable sections?
Practical activity
Create a one-page test record for this lesson. Include expected values, measured results, equipment used, risks controlled, defects found and the final proven condition.