The DS3800NTCF1A1A is a thermocouple condition card designed by GE for the Mark IV series. The MKIV is GE’s steam/gas turbine management system, which has triple-redundancies on all important protection parameters and controls. These back-ups allow the MKIV the option to shift control as necessary to keep the system running if a particular chipset experiences an issue, thus minimizing downtime.
The Mark IV system maintains temperature control by using feedback from thirteen thermocouple cards. The objective of this feedback loop is to maintain a constant firing temperature and to reduce fuel flow to prevent overheating of the turbine. Deviation of even one card can cause a resulting bias in the entire system, which is why it is important that all thermocouple cards in the system stay in good working order. Poor statistical input may lead to engine and/or combustor issues.
The DS3800NTCF1A1A has two PCB mating connectors. One is marked 218A4637-P4 8933. The other is marked 218A4553-1 A/mp 533002-1 8931.
The DS3800NTCF1A1A has seven test points, five jumpers, four rotary potentiometers, and a single resistor network array. Resistor networks and rotary potentiometers may both be used for voltage division.
The DS3800NTCF1A1A has extractor/installer clips inserted in the right corners. These nylon clips help with both installation and extraction of the board. During installation, technicians may use these clips as handles, which keep them from handling components. During extraction the clips act as a lever point, allowing technicians to pull the board from a tight-seated position.
The DS3800NTCF1A1A has eight circuits. These include hex inverting gates with six independent gates that perform the logic INVERT function, and octal buffers and line drivers with 3-state outputs with improved fan-in, high fan-out, and 400-mV noise margin.
The DS3800NTCF1A1A is built with both carbon composite (CCR) and ceramic-covered metal film resistors. Capacitors may be ceramic, polyester film, or other material.
Technical support for the DS3800NTCF1A1A and other MKIV components was provided by GE. This includes publications like datasheets and manuals.