GE Hydran 201i, Instruction Manual, Page: 27 / 300

Part 17997 Rev. 6, March 2011 1-1
Chapter 1
Introduction
This Chapter is an introduction to the Hydran 201 i System. A description of the various
components of the system is also provided.
1.1 THE HYDRAN 201 I SYSTEM
The Hydran 201 i System is a continuous, on-line, intelligent dissolved gas monitoring
system. Its uncompromising accuracy and reliability, and its features are key to its
worldwide acceptance as a true transformer fault prevention device:
• A direct and continuous combustible gas-in-oil digital reading (0–2,000 ppm H
2
)
• An isolated, analog 4–20 mA output
• Two adjustable gas alarm set points
• A System Fail alarm
• A sensor test feature
• A very wide temperature range for all-weather outdoor operation
• An extremely high immunity to electrical surges, radio-frequency interferences and
electrostatic discharges
Besides these essential characteristics, the Hydran 201T i intelligent dissolved-gas monitor
enjoys the benefits of full digital processing and is equipped with the following additional
high-value features:
• Adjustable hourly and daily gas trend computation (ppm change during the target period)
with alarming
• History logging of data and events with date and time stamping
• Serial communications with a host computer (RS-232 or RS-485)
• Networking capabilities (up to 128 units) and modem control
• Self-test on power-up
• All-software calibration
• Remote or local configuration and program upgrading
• Hydran Host computer software available from General Electric Canada
• Full stand-alone capabilities when the host computer is not needed
• Sensor self-test and sensor status