General Electric H201Ci-1 Sensor Horizontal Installation

Description

If the H201Ti is linked to a Hydran 201Ci-1 Controller, power them up and verify the H201Ci-1’s operation by observing the following LED’s and indicators:

The Supervisory Link Supply indicator (green, DS12) is lit.

The Heater indicator (yellow, DS8):

It must initially be lit if the ambient temperature is below approximately 25 °C (77 °F).

After a while, it must flash as the enclosure temperature reaches the above set point.

It must remain off if the ambient temperature exceeds the set point.

The two alarm indicators of the door-mounted push-buttons are off.

The Alarm 1 (Gas High) indicator (yellow, DS10) is off.

The Alarm 2 (Gas High-High) indicator (yellow, DS9) is off.

The System OK indicator (yellow, DS11) is lit.

The Hydran 201i contains a power supply that can accommodate 115/230 V AC 50/60 Hz single phase (factory set) and rated 475VA maximum. A 10 A to 15 A circuit meeting these requirements must be available for the Hydran 201i at the time of installation. The installation must be done in accordance with local wiring regulations.

System interface issues
The electrical grid connection signal of a 200MW heating unit in a certain power plant only has one way to DEH. During the normal operation of the unit, the auxiliary contact of the electrical grid connection malfunctioned, causing the turbine to trip. Measures taken: Use shielded communication cables, increase redundant contact signals, and perform a 2-out-of-3 logic judgment.
Examples of DCS failures caused by human factors
The failure of DCS caused by human factors is also common in the production process. This includes incorrect operations caused by personnel, incomplete management systems, and failure to follow the prescribed work steps.

Failure to follow the prescribed work steps
(1) The # 12DPU of the Xinhua XDPS system DEH in a certain power plant malfunctioned and was replaced online using DPU spare parts from the small machine MEH system. After replacing the DPU, only the # 32 main control DPU was copied to the # 12 auxiliary control unwritten electronic disk. In essence, it only kept the memory content of the auxiliary control DPU consistent with the main control, while the content of the # 12DPU electronic disk remained MEH small machine control logic. After the system power outage and soot blowing, # 12DPU was sequentially started as the main control. Due to its logic being MEH logic instead of DEH logic, system communication abnormalities, data flickering, abnormal screen display, and inability to operate the human-machine interface station were caused. After re powering on # 12DPU, copying # 32DPU logic, and writing to the disk, it works normally.
(2) The HIACS-5000CM control system of a certain power plant involved the replacement of remote I/O cards in the circulating water pump room. The online replacement operation steps were not carried out, and the cards were not activated to enter the working state, resulting in a mismatch between the on-site equipment status and the DCS screen, and the equipment could not be controlled. After performing the online replacement sequence, the system is functioning normally.

Misoperation by personnel
(1) During the operation of a certain power plant unit, workers mistakenly activated the DCS relay cabinet relay during defect handling, causing the induced draft fan to trip and the boiler to MFT.
(2) The DCS card of a certain power plant malfunctioned. During the process of replacing the card, the staff did not carefully check the equipment and the card jumper was incorrect, resulting in the newly replaced card being burned.
Incomplete management system
(1) The DCS system management system of a certain power plant is incomplete, and there are no regulations for software upgrades, backups, and other work. The auxiliary network water treatment POK1 operator station was not backed up after upgrading and patching. The hard drive of the operator station malfunctioned. After system recovery, due to the lower software version, communication with the network was not normal and the data did not refresh.
(2) The management of the operator station in a certain power plant was not strict, and the USB port and optical drive of the host placed in the central control room were not effectively sealed. During the night shift, some operators used the operator station to play games and watch movies, resulting in the operator station crashing.

Examples of DCS failures caused by external environmental factors
The number of DCS failures caused by external environmental factors is relatively small compared to the first two types of problems, but they also occur occasionally in actual production processes.
(1) The air duct in the electronic equipment room of a certain power plant is located above the DPU cabinet. Due to design and other reasons, fire water enters the DCS cabinet through the air duct during unit operation, resulting in water ingress and burning of DPU, servers, and other equipment, leading to unit shutdown.
(2) The remote IO cabinet in the circulating water pump room of a certain power plant was not tightly sealed at the bottom, causing winter mice to enter and build a nest at a high temperature above the cabinet, ultimately causing the remote IO to be disconnected from the dual network.
(3) The sealing of the electronic equipment room in a certain power plant is poor, and the dust accumulation in the card and DPU is severe. There have been multiple failures. After taking measures such as improving the sealing of electronic rooms and installing air conditioning, faults such as card and DPU were basically eliminated.