Page 341 - Electronic Mechanic - TP - Volume - 2

ELECTRONICS MECHANIC - CITS

EXERCISE 226: Demonstrate Familiarization with PMU
and different terminals of Micro master AC

Drive

Objectives

At the end of this exercise you shall be able to:
• to demonstrate familiarization with Phase Measurement Unit
• to demonstrate the different terminals of Micro master AC Drive

Requirements

Tools/ Equipments/ Instruments Materials/ Components
• Phasor Measurement Unit - 1 No. • Desktop/ Laptop (Latest specification) - 1 No.
• instrument transformer - 1 No. • PLC-Any Brand-Dismountable - 1 No.
• gaps receiver - 1 No. • Pointer - 1 No.
• phasor date concentrators - 1 No.
• communication infrastructure - 1 No.
Procedure

PMU ( Phasor Measurement Unit):- A Phasor Measurement Unit (PMU), also known as a synchrophasor, plays
a crucial role in electric systems by enhancing operators’ visibility into the vast grid network. Let’s delve into what
PMUs are and how they contribute to grid reliability.
PMUs capture samples from waveforms in quick succession and reconstruct the phasor quantity, resulting in a
measurement called a synchrophasor.
These synchronized measurements are crucial because any frequency imbalances (due to supply-demand
mismatches) can stress the grid and potentially cause power outages.

PMU also measure the frequency in the power grid.
1 Micro master AC Drive Overview:
The Micro master AC Drive is a type of variable frequency drive (VFD) manufactured by siemens. It is used to
control the speed and torque of AC motors in various industrial applications.
These drives are commonly used for pumps, fans, conveyors, and other machinery.
2 Terminal Identification:
The Micro master AC Drive has several terminals, each serving a specific purpose. Here are some

Key terminals:
Power Supply Terminals:-
L/L1, N/L2, L3: These terminals connect to the power supply. They carry dangerous
voltages even when the inverter is not operational.
U1/L1, V1/L2, W1/L3: These terminals are also part of the power supply connection.
Motor Terminals:-
U, V, W: These terminals connect to the motor phases.
U2/T1, V2/T2, W2/T3: These are additional motor terminals, depending on the frame size of the drive.
Other Terminals:-
DC+/B+, DC-, B-: These terminals relate to the DC bus voltage.
DC/R+: This terminal is used for braking resistors.
C/L+ and D/L-: These are additional terminals for specific functions.

324