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Gangguan elektromagnetik berupa conducted emission noise yang ditimbulkan oleh inverter pada sistem photovoltaic (PV) off-grid telah berhasil dikarakterisasi. Noise yang merambat pada jalur konduksi dihasilkan dari fenomena switching inverter untuk proses konversi daya dari listrik searah (DC) menjadi arus bolak balik (AC). Standar IEC 62920:2017 dan CISPR 25:2016 digunakan untuk mengukur noise yang dihasilkan oleh inverter di sisi DC. Pengukuran conducted emission noise pada inverter dilakukan dalam tiga kondisi, yakni kondisi tanpa beban, terhubung dengan beban lampu pijar 60 W, dan terhubung dengan beban lampu pijar beserta dimmer untuk variasi daya. Pengukuran dilakukan pada lima buah inverter dengan kapasitas daya dan jenis keluaran (output) yang berbeda-beda, yaitu 200 W, 300 W, dan 700 W untuk tegangan keluaran modified sine wave serta 500 W dan 1.000 W untuk tegangan keluaran pure sine wave. Hasil pengukuran menunjukkan bahwa pada kondisi inverter terhubung dengan beban lampu pijar beserta dimmer, inverter model pure sine wave 500 W dan 1.000 W memiliki peak noise level yang cukup rendah dan berpotensi lebih sedikit untuk menimbulkan gangguan elektromagnetik di sisi DC.

The internet of things (IoT) has allowed for ubiquitous measurement. Infant incubator temperature is one of crucial parts that need to be measured, especially for the stability and uniformity temperature. Based on the interpretation of IEC 60601-2-19, we proposed measurement method using IoT with the message queue telemetry transport (MQTT). In the 10,000 packet, the result shows the quality of service (QoS) level 2 of the system has the highest delay, however it has the lowest packet loss data than the other QoS. For 1 hour, the uniformity result and stability can fulfill the standards. Uniformity of 32°C, the lowest difference is point C with 0.32 °C, and the highest difference is point B with 0.75 °C. Uniformity of 36 °C, the lowest difference is point B with 0.27 °C, and the highest difference is point C with 0.79 °C. The stability of 32 °C and 36 °C is 0.32 °C and 0.44 °C, respectively. Moreover, the Kruskal Wallis test shows the highest difference average from point M is point A and B. It occurred because of the point A and B located far from the heater part, so the point A and B colder than point C.

Infant incubator is one of MEEs (Medical electrical equipment) that is largely used to preserve preterm and sick babies from postnatal stressors. However, their motors produce high electromagnetic fields (EMFs) which could affect the incubator as well as its occupants. In this paper, it has been done the EMF measurement to study and to quantify the level of EMF by mapping the magnetic field distribution inside the compartment of infant incubator. Measurement method was conducted on three layers from the mattress by magnetic near field probe and Spectrum Analyzers. The result showed that by p $\mu \mathrm{T}, 0.98\mu \mathrm{T}$ , and 0.97 $\mu \mathrm{T}$ , at first, second and third layer on every stage of heater level. This EMF is far below the standard level for magnetic field ERLs for exposure of limbs, and head and torso at 0 Hz to 5MHz by the IEEE and ICNRP.

One of the parameters to be tested on the sphygmomanometer is the deflection of the dial. The testing method based on the standard uses manual air pressure to increase the pressure so that the dial is pointed to the desired pressure. This paper proposed an automatic testing method using a proportional-integral-derivative (PID) controller based on arduino to control the pressure. The result shows that the system is not suitable to use. The process capability index at each given setpoint is less than 1. This low cost proposed testing method still needs to be improved and could become an alternative solution for laboratory testing of the sphygmomanometer.

LED lighting market share shows an ever increasing trend. This is driven by some of the LED advantages, such as higher efficiency, wide range of colors, and longer lifetime. LED is a DC device, and to power it from AC supply, like in household or street lightings, a driver is required to convert AC to DC supply. In addition, LED driver is preferred to operate in constant current mode in order to avoid LED thermal runaway. Also the driver has to have high efficiency, low THD (total harmonic distortion), and comply with electromagnetic emission limits. In this paper, a prototype of primary-side-regulated AC-DC flyback LED driver has been implemented. It has a constant output current of 0.990A 0.012A across the output voltage 15.59V – 42.80V. Measurement results show that the achieved efficiency is up to 88.55%, current harmonics comply with IEC 61000-3-2, and conducted emission levels comply with CISPR 15.

A remote system for controlling and monitoring the temperature inside the compartment's infant incubator on a mobile device is developed. The system composed of an Arduino Uno, an HC 05 module, a DHT 11 sensor, a relay, and a heater. The system has advantages on providing more sterile compartment's environment and easier control/monitor infant incubator. The developed system is proven to be used for controlling and monitoring infant incubator remotely. The average temperature response of the developed system is 0.397 °C/mins, and maximum communication distance between the developed system and the mobile phone is 12.25 m.

One of the key components in switching power supplies is the main switch, of which MOSFET is commonly used. High dv/dt and di/dt are inherent in MOSFET switching operation, and so it is a major source of electromagnetic emissions that may fail the standard limits. In this paper, effects of MOSFET gate driving on conducted emissions are examined. Measurements are made on a prototype of flyback LED driver. It is found that increasing gate resistance could suppress the drain turn-off oscillation voltage. By experiment, an external gate resistance necessary to reduce emission below limit lines is obtained. Anti-parallel diode speeds turn-off up but increases EMI level. It was confirmed that the noise upper 20MHz was originating from the drain voltage spike. Instead of anti-parallel, the diode can be also connected in parallel to the gate resistance. In this way, it can facilitate faster MOSFET turn-on transients, and therefore power efficiency had shown an improvement but without increasing EMI level.

The quality of medical devices is an important thing to establish the anamnesis, diagnosis and also treatment of patient. Arterial pressure measurement as one of the first indicators in the Hypertension Management Guidelines requires the accuracy as well as their function. Error in the detection of blood pressure should not occur during measurement because the errors will also make failure in determining the diagnosis and therapy for hypertensive patient, related on their hypertensive classification. Clinicians requires accurate medical measurement in order to monitor patients, diagnose diseases and deliver treatments. The failure of detection will certainly have diverse effects. Preliminary studies have shown that differences in results that are generated by two types of blood pressure devices, aneroid sphygmomanometers and digital blood pressure. The differences between both devices are 2-11, 6 mmHg for Systolic and 0.8 - 10.3 mmHg for diastolic. This differences led a new insight to the accuracy of blood pressure devices that are widely used in medical circles and the critical value of the accuracy of the sphygmomanometer can be the basis for determining clinical blood pressure classification. Therefore, it is necessary for medical staff to get information about the accuracy of blood pressure devices and its critical parameters in determining blood pressure, it is also necessary for a regulation on a blood pressure classification based on the type and level of accuracy of measuring instruments.

This paper focuses on the Electro-Magnetic Interference Risk Analysis of medical devices via the evaluation of their susceptibility. Medical devices for supporting patients' life are frequently applied in vulnerable environments such as hospitals and surgery rooms. The susceptibility analysis is based on a GTEM testing method derived from ANSI C63.18 and is applied to three different medical devices, namely ECG, patient monitor and an infusion pump. Specific interference signals are generated simulating telecommunication devices, more specifically Wi-Fi, GSM, and PMR. The results showed that especially the signals transmitted by the PMR may affect the performance of medical devices.

Infant incubator is one of the most important medical devices for newborn survival, especially preterm. However, aside from its benefits, some irregularities can be found on the devices that could lead to infant mortality, such as temperature deviations. The problem can be minimized by testing the infant incubator temperature parameter in accordance with IEC 60601-2-19 standard. However, there are various types of temperature sensors for related tests. Therefore K-Type and T-Type Thermocouples are compared in order to provide recommendations for infant incubator testing. The measurement technique used were referred to the instructions stated in IEC 60601-2-19 sub-clause Stability (with tolerance ±0.5oC) and sub-clause Uniformity (with tolerance ±0.8oC). For K-type thermocouples, the highest stability results at 32oC is -0.2oC and at 36oC is -0.4oC, while the highest uniformity results at 32oC is -0.1oC and at 36oC is -1.6oC, with the uncertainty of 1.7oC. For T-type thermocouples, the highest stability results at 32oC is 0.4oC and at 36oC is -0.4oC, while the highest uniformity results at 32oC is 0.7oC and at 36oC is 0.8oC, with the uncertainty of 0.3oC. The results of the independent t-test showed a different average, where the T-type thermocouples was higher than the K-type thermocouples. In other words, T-type thermocouples could be recommended for infant incubators testing.

Simulator tekanan darah biasa digunakan sebagai nilai referensi dalam mengevaluasi tensimeter otomatis (NIBP monitor). Penelitian sebelumnya menunjukkan bahwa simulator tekanan darah dapat dibuat dengan menggunakan micro air pump berbasis motor dc sebagai aktuator. Namun, hasil simulasi yang dihasilkan berbeda untuk setiap merek tensimeter. Hasil analisa menunjukkan bahwa laju inflasi dan deflasi yang berbeda mempengaruhi karakteristik simulasi. Studi ini bertujuan untuk mengembangkan firmware simulator baru berdasarkan nilai pulse width modulation (PWM) dan gradien inflasi-deflasi untuk meminimalkan pengaruh tersebut, sehingga simulator dapat memberikan hasil yang sama untuk berbagai jenis dan merek NIBP monitor. Validasi dengan simulator referensi dan evaluasi dalam kondisi statis dan dinamis menunjukkan simulator yang dikembangkan cukup andal untuk melakukan pemeriksaan awal, termasuk evaluasi pengulangan hasil tensimeter otomatis. Kata kunci: NIBP monitor, PWM, NIBP simulator, gelombang osilasi, lajuinflasi, laju deflasi ABSTRACT Blood pressure simulators are commonly used as reference values in evaluating NIBP (noninvasive blood pressure) monitors. Prior research shows that an NIBP simulator can be made using dc motor based micro air pump as the actuator. However, the simulator yield different results for different brands of NIBP monitor. The analysis result showed that inflation/deflation rates do affect the simulation’s characteristic. This research aims to develop a new simulator firmware based on pulse width modulation (PWM) values and rising-falling slope to minimize the corresponding effect so that the developed simulator could generate the same result for various types and brands of NIBP monitor. Validation using a reference simulator and evaluation in static and dynamic conditions showed that the developed simulator is reliable enough to do a quick pre-checks, including assessing the repeatability of NIBP monitors. Keywords: NIBP Monitor, PWM, NIBP Simulator, Oscillometric Waveform, Inflation Rate, Deflation Rate

Two important parts of wireless power transfer are transmitter circuit and receiver circuit. Previous research has been completed which use CMOS H-Bridge in transmitter and full wave rectifier in receiver. This paper presented simple design of transmitter circuit and optimization of receiver circuit in rectifier circuit with transient analysis and Fast Fourier Transform (FFT) from LT spice software. The simple transmitter circuit used an integrated circuit (IC) NE555 with push-pull as oscillator circuit and LC resonant, while the receiver circuit used LC resonant, rectifier circuit, CLC filter for smoothing direct current (DC) output and 500 Ohm as load. The circuit design had resonant frequency of 250 kHz on both of transmitter and receiver, which comply with Power Matters Alliance (PMA) standard. The optimization of rectifier circuit had been done by comparing output of power load when it used basic rectifier (full wave), voltage doubler (dickson circuit and Villard circuit) and voltage multiplier (cockcroft-walton circuit). The results showed the receiver with Dickson circuit as rectifier has the highest efficiency compared to other rectifier circuits with efficiency of 10.93 % when it used coupling coefficient of 0.99, because Dickson rectifier has resonant frequency that is closest to 250 kHz and the highest level power, compared to other rectifier circuits.

Electrocardiograph endurance test system ha s two work process es like defibrillator. Charg ing process produce s energy stored in capacitor (E S ) and discharges process produce defibrillation energy. Defibrillation energy without connect to electrocardiograph (E 2 ) at test system is influenced by the resistance values of inductor (R L ). In previous research, test system only produce s E 2 = 19,83 joule, this is caused by the inductor used with value R L = 72 Ω . The purpose of this research is to select inductor resistance value to get good and efficient value E 2 . Range value R L used in test system was 1–10 Ω , based on standar International Electrotechnical Commission (IEC) 60601-2-27 clause 201.8.5.5.2 . Voltage measured in point 100 Ω every time interval (∆t) 0,02 ms obtained from multisim software simulation. The result of simulation indicated if peak voltage increased, then value R L was used approach zero. In other side, measure d Voltage data was used as parameter to calculate total E 2 in every range of R L value, then result E 2 total was compared to E S value to get energy ratio value . Value R L = 1 Ω was the most effi cient because has ratio energy value 98,45% with E 2 = 393,80 joule, while energy ratio when R L = 10 Ω was not effi cient because only had energy ratio value 89,58% with E 2 = 358,33 joule .