September 2001
The determination of moisture in oil is an essential part of a comprehensive transformer maintenance programme. Excessive moisture content in oil causes accelerated ageing of the insulation materials and reduces their dielectric strength.
Vaisala's microprocessor-based HMP228 transmitter provides online transformer oil measurement of the moisture content and temperature. It incorporates the latest version of Vaisala's thin film polymer sensor and its operation is based on the measurement of changes in capacitance as the thin film absorbs water molecules from the oil.
Kobus de Villiers - Wika
Regular Features
Forum
Clipboard
News and products
HellermannTyton mindbender
Drives, Motors and Switchgear
Decoding the motor nameplace
M Baugh (Danfoss) ,
The nameplate provides the key to the motor
What high efficiency really means
A S Sohler (WEG New Zealand) ,
A number of motors classified as high efficiency are substantially less efficient than others
Engineering Projects and Plant
Johannesburg Water - Olifantsvlei wastewater treatment works
Plant Maintenance and Refurbishment
Optimisation of plant maintenance and refurbishment budgets
H Fourie (Rotek Engineering) ,
Planned maintenance saves money in the long run
Sensors, Switches and Transducers
Making sensors and transducers smarter still
K Barnfather (KAB Instruments) ,
Connecting instruments via Ethernet means savings to the user
Temperature Measurement and Control
Test, Measurement and Calibration
Principles of non-contacting temperature measurement
J L Bonkowski
Infrared temperature sensors are accurate and provide numerous advantages
