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TRAFOP-CZ s.r.o.
Neratovická 1043
Kostelec nad Labem

(+420) 602 141 834


Monitoring transformers

The company TRAFOP-CZ, Ltd. offers delivery and installation of a monitoring system.


monitoring of levels of:
  • Dissolved hydrogen
  • Water
  • Carbon monoxide
in the transformer oil filling
Detect transformer faults at their earliest stage – hydrogen monitoring

Hydrogen is produced to a greater or lesser extent by all transformer faults. Calisto 2 measures dissolved hydrogen continuously and accurately. Even at the earliest stages of fault development, both thermal and electrical stresses on transformer oil will generate dissolved hydrogen. Such highly mobile hydrogen is quickly distributed throughout the oil, providing an early and reliable fault signature. Calisto 2 excels at timely and accurate low-level hydrogen measurements. When installed on your critical transformers, Calisto 2 provides the earliest possible fault detection, and allows accurate real-time monitoring of subsequent fault evolution.


Monitorování stavu pevné izolace

Insulation integrity is vital to your transformer’s operation. Moisture build-up and transformer overheating are two conditions which may lead to irreversible insulation degradation. Carbon monoxide is a by-product of cellulose degradation; anomalous amounts of carbon monoxide may be generated when localized cellulose overheating occurs. Calisto 2 provides a dependable measurement of the CO baseline, and will alarm on a sudden increase of CO concentration. Timely follow-up with laboratory DGA and furan analysis will enable early detection of accelerated aging of solid insulation, before significant and irreversible damage is incurred. In combination with polar products and acids, moisture can significantly affect the dielectric properties of insulating fluids and materials. Engineered for reliability, Morgan Schaffer’s solid-state moisture-in-oil sensors deliver exceptional accuracy when compared against laboratory measurements and moisture-in-oil standards.
Precision temperature measurement and proven conversion algorithms are used to report moisture content in parts per million (ppm), %RS at 25°C or %RS at a specific transformer temperature.


Temperature conditioning

Oil temperature variations compromise the accuracy of on-line gas measurements. Gas solubilities and diffusion rates vary significantly with temperature, and the variations depend on oil type, age and purity.

Calisto 2 eliminates the impact of oil temperature variations by heating or cooling the oil to a precise standard temperature. This enables concentration measurements of unequalled sensitivity, stability and accuracy.


Gas measurement technology

Morgan Schaffer’s proprietary second-generation gas measurement cell sets a new standard for accuracy and low-level measurements of both H2 and CO in transformer insulating fluids. Every Calisto 2 monitor is calibrated using certified gas mixtures traceable to NIST and Morgan Schaffer’s IEC/ISO 17025 certified oil-testing laboratory.


Oil circulation

For reliable readings and fast response to transients, Calisto 2 continuously draws representative oil from the transformer using an internal electromagnetic pump with an outstanding reliability record. An oil flow monitoring system ensures adequate flow is maintained at all times.

Cost benefits

Investing in a Calisto 2 will substantially reduce operating costs:

  • Reduced unplanned outages
  • Prevent irremediable deterioration of solid insulation
  • Reduce downtime from false alarms
  • Optimize your maintenance schedule
  • Monitor critical equipment continuously


Technical benefits
  • Unit can be field installed and commissioned in less than 12 hours
  • Easily integrated to existing monitoring systems
  • Reliable, accurate and stable signals
  • Fast response to fault onset
  • Vacuum tolerant


Characteristic features
  • Accurate Hydrogen and Carbon Monoxide measurements
  • Continuous moisture monitoring
  • High sensitivity and wide range
  • Continuous oil circulation with flow monitoring
  • Proven dissolved gas extraction technology
  • Optional Calisto Expert Series accessories


Versatile connectivity
  • Calisto 2 can be operated on-site using its standard day/night VFD display and 3-button interface panel
  • Three isolated 4-20mA outputs are provided, for hydrogen, carbon monoxide and moisture measurement transmission
  • Five NO/NC relays can be configured with regular or fail-safe logic to react to measurement level alarms, trend alarms or self-test errors
  • Digital communication can be established using local USB-2
  • An optional IEC 61850 kit is available
  • An isolated 4-20mA oil temperature input can also be used with Morgan Schaffer’s Calisto
  • Expert Series Oil Temperature Sensor
  • Other options include a fiber-optic temperature input kit, modem, and wireless modem