1. PS 1: Question 3 Advantages and disadvantages of each thermal philosophy
A transformer is a complex protective object. Life time management and condition based monitoring needs more information.
To determine the loss of life or the condition of the whole transformer due to:
Dielectric stresses
Chemical stresses
Thermal stresses
Dynamic stresses
Sensor setup
adapted to an economical
cost-value ratio

2. Measuring quantities:
On-line Monitoring Concept for Power Transformers
Important Parameters to provide an Early Warning System and Life Management Support by means of On-line Monitoring
Information about:
Measuring quantities:
Load and operation conditions
and history 
voltage (HV), load current (HV),
tap changer position
Transient conditions 
peak values of voltage (HV)
Thermal aging /Hot-spot calculation 
oil temperature and load current (HV)
Condition of insulation and oil 
H2 in oil, moisture in oil
Efficiency of cooling system 
oil temperatures, top and bottom
Load tap changer condition 
position, counter,
power consumption of motor drive
Operation time of pumps and fans 
circuit state of pumps and fans

3. On-line Monitoring Concept for Power Transformers
Example of Hardware for Monitoring Applications
Based on a powerful data logging device
Data storage capacity 256 MByte..1 GByte
Analog Inputs
Digital inputs and outputs
Virtual channel for calculations
Event controlled storage
Remote access by Modem, GSM, LAN
Alarms by means of digital outputs, SMS or
1 Interface LAN - TCP/IP
2 Interfaces RS232
Example of
a data logging device

4. On-line Monitoring Concept for Power Transformers
Remote Monitoring, Example of a Network Configuration
Remote Monitoring Computer
Display of measurements in diagrams
Down-load of stored data
ASCII-export for MS-Office applications
OPC-Server