• Gas chromatography (GC) technology for precise and accurate readings
  • Built-in moisture and solubility coefficients for all common insulating fluids
  • Proprietary Morgan Schaffer cell and chromatographic method
  • Enhanced self-diagnostics
  • Vacuum tolerant
  • Enclosure temperature and oil temperature conditioning
  • Factory-installed carrier gas manifold for trouble free start-up and convenience
  • Built-in oil circulation and flow monitoring
  • Communication protocols: Modbus, DNP3, optional IEC 61850
  • Substation hardened communication electronics
  • Early detection of impending failures
  • Cost-efficient condition-based maintenance
  • Easy installation and integration within existing operations
  • Easily upgrade between detection and diagnostic models for optimal fleet deployment strategies
  • Virtually maintenance-free: annual visual inspection
  • More than 15 years of expected useful operating life
  • 30 months standard warranty on all Calisto products
  • Fully functional even in the harshest environments
  • Use as a standalone product, networked to existing SCADA system, or as part of a doblePRIME Condition Monitoring Platform

Calisto online DGA monitors for power transformers and other oil-filled electrical assets

Calisto detection monitors:

Hydrogen + moisture

Calisto is an online DGA detection monitor that provides precise and accurate hydrogen and moisture readings with unequalled stability at low concentration levels. Detect and monitor incipient faults using interference–free hydrogen readings. Correlate moisture behavior with load while monitoring long-term trends.

Calisto 2
Hydrogen, moisture + carbon monoxide

Calisto 2 is an online DGA detection monitor that provides additional measurement of dissolved carbon monoxide, combining early fault detection (hydrogen) and cellulose degradation monitoring. Carbon monoxide is a gas often generated in large quantities when transformer cellulose overheats.

Calisto diagnostic monitors:

Calisto 5
5 fault gases + moisture

Calisto 5 is a multi-gas online DGA diagnostic monitor for the measurement of five Duval Triangle gases through a proprietary chromatographic method.

Calisto 9
Complete DGA + moisture

Calisto 9 is a multi-gas online DGA diagnostic monitor that measures all seven fault gases plus oxygen and nitrogen with industry-leading detection limits.



doblePRIME PD-Guard
Morgan Schaffer Myrkos

Doble Engineering Company

Doble Engineering Company