1. G

    Li-ion cell charging module resistor selection?

    Greetings. A vendor selling TP4056-based 5 V charging modules for Li-ion cells specified the following resistance values and resulting current for selecting the current-programming resistor: R (kΩ) I (mA) 30 50 20 70 10 130 5 250 4...
  2. Vatleachna

    Help me understanding the delta and star in 3 phase voltage !

    To solve this question all I know is I had to change the delta source to star shape (wye), then to find the current is using ohm law's with the voltage divided by the impedance which in the same line I'm confused with this question, does the position of the source in delta and impedance matter...
  3. nickhess

    Adapting an old CRT Viewfinder ( 9.3 V DC / 2.7W )

    Quarantine project: Adapting a Sony BFV-20W viewfinder Scroll down to skip the background info As a cinematographer, I've always really felt most comfortable shooting with a viewfinder. However modern electronic viewfinders all exist in the "prohibitively expensive" class of filmmaking...
  4. E

    DC biasing, headroom, clipping in MOSFET amplifiers

    Okay so my question relates to biasing and threshold voltage in a MOSFET amplifier. So in an amplifier the clipping occurs when the signal hits the power rails according to all the reading I’ve done. That’s how much voltage swing you supposedly have before clipping. So if you have an 18 volt...
  5. Lambo Av

    Voltage Magnitude, Phases, Current for Bus (Load Flow)

    Say there are 3 buses of: Bus 1: Slack bus with a voltage source of E=1.0 and phase of 0° Bus 2: a generator and a load. Bus 3: a load. The line impedance are given below: z12 = 0.05 + j0.1 z13 = 0.02 + j0.05 z23 = j0.05 z11 = -j100 z22 = infinity z33 = -j40 The generators and loads are given...
  6. Lambo Av

    Given 3 buses with line impedance, generators and loads provided, where must the protection circuit be allocated?

    The 3 buses are Bus 1: Slack bus with a voltage source of E=1.0 and phase of 0° Bus 2: a generator and a load. Bus 3: a load. The line impedance are given below: z12 = 0.05 + j0.1 z13 = 0.02 + j0.05 z23 = j0.05 z11 = -j100 z22 = infinity z33 = -j40 The generators and loads are given below...
  7. M

    How to calculate the current of a circuit if a resistor is placed with load in series?

    Assume we provide a load with its rated voltage, suppose it should draw the current it need at such voltage level. However, what if we place an additional resistor in series with the load, can the load still draw the same current as it needed?
  8. Sprayman

    Help measuring voltage spike with oscilloscope

    I am tasked with confirming a report that said we had a large voltage spike (~400v I believe) when turning some equipment on. I went and put the oscilloscope on our main that is in the same box for the switch for the equipment. I throw the switch and see my measurements react a little but I...
  9. Electronic_Maniac

    Questions regarding Function Generator - AFG3000C

    I am having this new Function generator - AFG3000C I am having difficulty in understanding certain terms related to this FG. I have tried online searches, but I couldn't get what I was looking for. Being a newbie, I request you all to help me understand my queries in simple terms. Could you...
  10. Lambo Av

    2 Generators connected to bus. Maximum, minimum voltage across light, peak voltage, pulsation

    2 generators are connected to the bus below. Given V1 = 300V, 50Hz V2 = 400V, 60Hz When the switch is opened, calculate i) the maximum and minimum voltage across both light 1 and 2. ii) peak voltage across both lights iii) maximum number of light pulsation How do I solve the issue above? Any...
  11. x11

    Adjusting voltage

    I have a servo and an actuator, both connected to a breadboard, needing 7v and 12v power respectively. I don't want to use batteries. How would I adjust the wall plug 120v to 7v and 12v respectively? There are technically adapters on amazon, but I am not sure how to connect them to my breadboard.
  12. C

    Theoretical values for ”natural frequency”, currents and voltage at electrical resonance.

    I am supposed to calculate the theoretical values for ”natural frequency”, currents and voltages at electrical resonance for this circuit. I should use the measured values for the resistance and the inductance of the coil. Also the measured value of the capacitance to the capacitor. The...
  13. T

    diode in series and parallel working principle?

    Hello, I would never thought I could not understand a circuit made out of diode but here I am. 1-the first circuit is two diode in series, when i measured the voltage between the them I found it half the voltage of the source which is not logic for me!!! as there is no current flowing through...