The criticality level of equipment used at PT PLN (Pesero) power plants at present is using the Maintenance Priority Index (MPI) method. The calculation for the criticality rating of MPI equipment uses 4 (four) types of calculations, namely SCR, OCR, ACR and AFPF. To add to the consideration in determining the priority of equipment maintenance, an additional calculation of the criticality level of PLTU Tarahan equipment is carried out using the Equipment Criticality Management method. The Equipment Criticality Management method has 4 (four) assessment perspectives, namely Production, Safety, Environment and Equipment Failure. Calculations that have been carried out on the top 100 (one hundred) equipment in the PLTU Tarahan SERP using the Equipment Criticality Management method, there are 85 (eight five) equipment that has “High” criticality and 15 (fifteen) equipment in the “Medium” criticality category. 15 (fifteen) equipment that has “Medium” criticality is equipment that has backup and part of common generating equipment.

Steam power plants (PLTU) are power plants that have the largest percentage of power plants owned by PLN. The main controller in a PLTU usually uses a Distributed Control System (DCS). The reliability of DCS in a PLTU must be maintained properly so that the power plant does not experience a control failure that causes the PLTU to stop suddenly. DCS PLTU Sebalang Unit 1 has used the FMEA method to determine its maintenance strategy, but the FMEA has not defined the function of the equipment, functional failure, the effect of failure, and criticality analysis (CA) of the equipment. failure mode prioritization has not been carried out. With the FMECA conducted in this study, the priority of the failure mode can be carried out effectively so that the priority determination of DCS maintenance can be carried out. Results of the FMECA that have been carried out, it is known that the failure that occurs in the DCS CPU has the highest RPN value (140). The maintenance strategy obtained from the FMECA results is preventive maintenance (PM), namely: 1) checking the power supply voltage, 2) checking the communication status, idle time status, load and CPU status, and maintenance run to failure (RTF) CPU replacement if there is damage to the CPU. FCS CPUs.