|The TSM9504 is a programmable temperature monitor. Visual display of all parameters, and interactive menu driven configuration procedures are selected via the monitor. The requirement on gas turbines is to monitor the variation of temperature through a cross section of the hot gas path.The monitor has to be able to accept signals from the plant, perform the necessary algorithm, present information to the operator and issue alarm and trip signals. Consideration must have to be given to self-diagnostics, commissioning facilities and the ability to store the healthy "as built" engine parameters.
The purpose of spread monitoring in the gas turbine application is to detect deterioration in burner nozzles, combustion chamber and/or gas path flow pattern. If operation is allowed with high temperature spread then damage may be caused to components in the hot gas path, particularly turbine driven rotor blades.
Gas turbine engine manufacturers make available thermocouple sets
located in the hot gas path downstream of the gas generator exhaust. Traditional ways of alarming unacceptable deviations have been to compare an individual thermocouple with the average and alarm if the difference exceeds a predetermined value.
This approach does not take into account the fact that the "as
new" engine does display acceptable deviations between the measured temperatures. In some cases large changes from the "as new" are allowed before an alarm condition is raised. For example:
- With the alarm level set at 50 degrees C deviation from the average, any individual thermocouple may be 49 degrees C low in the "as new" state.
- This measurement could move by +100 degrees or -1 degree before an alarm would be raised.
- 100 degree C move from the normal is considerable and represents unacceptable levels of mechanical damage.
- -1 degree movement would present a nuisance alarm.
The TSM 9504 temperature spread monitoring system is programmed to alarm on deviation from the "as new" condition as the absolute deviation.The "as new" value is determined by establishing a footprint.
The TSM 9504 has an interactive configuration facility for establishing the "as new" footprint, manipulation of set points and selection of commissioning mode for forcing of outputs. The footprint is established at points nominally evenly distributed between synch idle and full power. Alarms and trips can be set for the following:
- Any single t/c exceeding set point
- Average temp exceeding set point
- Individual deviation from mean exceeding set point
- Individual deviation from footprint exceeding set point
- Failed thermocouple inputs
- Touch sensitive or keypad operated screen.
- PLC Based System.
- Eight thermocouple inputs.
- Eight digital inputs.
- Eight isolated relay inputs.
- 24 VDC operation.
- 19 inch rack assembly, 6U high.
- Connection by multi-way connector.
The TSM 9504 can also be extended to suit specific customer requirements.
- Digital inputs or outputs can be expanded. Amount is dependent on mounting scheme.
- Analogue inputs and outputs can be expanded. Amount is dependent on mounting scheme.
Optional Mounting Schemes
- 19 inch rack mounting or wall mounted assembly.
From the main menu, the following screens can be accessed:
- Absolute temperature deviation from the eman.
- Individual combustor temperatures.
- Footprint configuration screen.
- Event history, details of the last 14 alarms.
- Trend screen.