GE Hydran 201Ti Troubleshooting Practice

GE Hydran 201Ti Smart Transmitter: A Complete Guide to On site Installation, Communication Networking, and Troubleshooting

In the operation and maintenance of high-voltage power transformers, online monitoring of dissolved gases in oil has become the core means of preventive fault diagnosis. The Hydran 201Ti intelligent transmitter launched by GE, combined with the 201Ci series controller, has built a highly sensitive and real-time responsive gas monitoring system. This article is aimed at on-site engineers, systematically reviewing the installation points, controller selection, communication network construction of Hydran 201Ti, and focusing on summarizing common faults and their troubleshooting methods to help users ensure stable equipment operation under complex working conditions.

System composition and core functions

1.1 Hydran 201Ti Intelligent Transmitter

Hydran 201Ti is a small temperature controlled cylindrical shell device that can be directly installed on transformer valves, with built-in gas sensors and microprocessor based electronic units. The shell protection level is NEMA 4X (IP66), suitable for outdoor and industrial harsh environments.

Monitoring gas types:

Hydrogen (H ₂)

Carbon monoxide (CO)

Acetylene (C ₂ H ₂)

Ethylene (C ₂ H ₄)

Measurement principle:

The combination of selective gas permeable membrane and combustible gas detector, combined with dynamic oil sampling system, achieves continuous monitoring of gas in oil.

Measurement range and accuracy (0-2000 ppm H ₂ equivalent):

Accuracy: ± 10% reading ± 25 ppm

Relative sensitivity:

CO：18% ±3%

C₂H₂：8% ±2%

C₂H₄：1.5% ±0.5%

Response time:

The time to reach a 90% step change is 10 minutes, suitable for rapid fault warning.

Output and alarm:

Standard analog output: 0-1 mA (non isolated)

Optional output: 4-20 mA (isolated, 1500V RMS)

Alarm contacts: Gas Hi, Gas Hi Hi, Fail (SPDT type, 60W/125VA)

Environmental adaptability:

Oil temperature range: -50 ℃ to+90 ℃ (optional high temperature adapter can reach+105 ℃)

Environmental temperature: -50 ℃ to+55 ℃

Oil pressure range: 0-700 kPa (vacuum not allowed)

Power supply: 100-230 Vac, ± 10%, 50/60Hz, maximum 350VA

1.2 201Ci series controller

Hydran 201Ti must be used in conjunction with a controller, and there are three main models:

201Ci-1 (Single Channel Controller)

Suitable for monitoring a single transformer, equipped with LED digital display, alarm contacts, analog output, and supports local RS-232 and RS-485 networking.

201Ci-4 (four channel controller)

Up to 4 201Ti devices can be connected simultaneously, supporting channel polling display and independent status LED indication. The optional expansion version provides independent alarm contacts for each channel.

201Ci-C (Communication Controller)

No display and alarm contacts, dedicated to managing up to 4 data streams of 201Ti, serving as a communication gateway between RS-485 network and upper computer.

1.3 Hydran HOST upper computer software

Hydran HOST is a monitoring software based on the Windows platform that supports:

Real time alarm and status monitoring

Upload historical data and display trend graphics

Download and Backup of Configuration Files

Remote firmware upgrade

Supporting operating systems: Windows 3.1/95/98/NT 4.0/2000/XP, hardware requirements: PC with 486 or above, 8-32MB memory, VGA display.

Installation and positioning: key to ensuring measurement effectiveness

2.1 Selection of transmitter installation location

On site experience has shown that the installation location directly determines the system response speed and measurement representativeness. The recommended order is as follows:

Preferred location: The straight section of the cooler return oil pipe, located on the outlet side of the oil pump

The oil flow velocity is high and the mixture is uniform, which can quickly reflect internal faults of the transformer.

Alternative location: Upper fuel injection valve or side wall valve of the fuel tank

Suitable for oil-free or natural circulation systems, but response time may be extended.

Not recommended location: bottom of cooler or oil drain valve

Slow oil flow and easy deposition of aged oil can lead to low or delayed readings.

Installation direction:

The transmitter must be installed horizontally to ensure the normal operation of the internal oil sample dynamic sampling system.

2.2 Valve and Adapter Requirements

Full bore gate valves or ball valves must be used, with an inner diameter of no less than 38mm (1.5 inches).

The standard brass adapter comes with a 1.5-inch NPT external thread.

Optional use of a 1-inch high temperature adapter with fins for high temperature conditions (temperature resistance+105 ℃).

2.3 Precautions for Controller Installation

The controller (201Ci-1/4/C) has a NEMA 4X casing and can be installed outdoors.

It must be installed on a vibration free structure or use a randomly provided rubber damping pad.

The installation height should be based on human eye level view and the cabinet door can be fully opened.

All communication cables must be threaded into metal hoses or hard tubes to resist electromagnetic interference (EMI/RFI).

Practical Communication Network and Wiring

3.1 Communication Port Types and Functions