Questions tagged [soft-starter]
The soft-starter tag has no usage guidance.
27 questions
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How can I override soft switch on dehumidifier so I can turn it on using a timer
My dehumidifier is switched on using a touchpad which controls its startup sequence. If I plug it in and supply current nothing happens until I turn it on using the touchpad. So I cannot cause it to ...
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Comparing Motor Starting Methods: Star to DOL vs. Star to Delta
Question:
I need to understand the differences between the two motor-starting methods:
Case 1: Start with a Star connection and then switch to DOL (Direct-On-Line) [I know this is not standard ...
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Soft starter for inductive loads (motors)
I am a beginner level EE working for a small company. There is a three-phase (whose only two are controlled) soft-starter project (for 1/4CV motors) that has never worked as intended. The company ...
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How to create external soft start for a BTS FET?
I want to create a hardware solution. The datasheet is here.
The circuit is shown below. I do not have access to the code in order to implement a soft start using a PWM. Is there a way I can create a ...
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Three phase motor with 3 sets of connections. Star, delta, and something else?
What's going on with this motor ? It's not simply wired into a star/delta starter. There's a 3rd option I'm not familiar with. The legend below and to the left shows Star/Star-Star/Delta.
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Soft-start circuit for highly resistive load - negating initial voltage spike
I am trying to design a soft-start circuit for one of my projects which has a relatively large resistive load (~1MOhm). I found the following example circuit from an answer for a previous post (12 V ...
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can a soft starter be used if the application requires high starting torque?
I want to use soft starter to protect the motor from high starting torque because the motor is set to start via DOL quite frequently. But wondering whether the application requires high starting ...
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Circuit diagram of controlled soft starter
Still learning about electronics. I want to build a soft starter circuit, I found this schematic.soft start schematic
I can understand the schematic, but there's a 7805 voltage regulator circuit at ...
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How to deal with very high current to DC motor
I am using a pickup truck starter motor to build a small crane-like loading arm. I want to control the direction of rotation using an H-bridge, however, when I turn on the mechanism the motor has a ...
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Electrician Theory: Delta Star Induction motor question
This is the question I am trying to solve:
A delta connected fully loaded induction motor draws 90A from a 400V supply when started direct online. Show by calculation the current at start up that the ...
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Is the RF/DC power on/off sequence for my simple radio beacon design good enough?
I'm using a RFPA5542 PA module. Does the power on/off sequence have to be followed exactly? Do I risk damage to the IC? I am delaying PA_EN by 2ms by an RC circuit of R13 and C5 and that is all. The ...
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Soft starter for AC motors
I want to build an AC motor soft start. The way I found is to regulate the voltage from 0 to 220 V (within 2 seconds) to eliminate the inrush current. I did it using Arduino to generate PWM to drive a ...
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Why is this precharge circuit not functioning?
Although this question sounds basic but, I have been trying to implement this precharge circuit to safely turn on the inverter without overloading the system, however especially when I powered it on, ...
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Wrong output with DC soft start
I have a Pi Pico project I am working on and I ran into a hiccup. I have a 12VDC soft start that I used from this thread.
I pretty much used the same thing, but I changed the MOSFET to IRF9620 .
I am ...
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12 V Soft-Start circuit
I'm struggling designing a soft-start circuit for my project. It's 12 V with up to 500 mA load. I'm looking for a ~1000 ms ramp-up time from 0 to 12 V. This is the circuit I have designed, which seems ...
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Why do some transformers trip circuit breaker. Eg a ups transformer. I need a soft start resistor details
I need a soft start for a ups transformer. Because when I power it with 230v ac it trips the breaker. I need a diagram to build my own soft start circuit.
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Design or selection of a capacitive-load soft start circuit
A circuit to soft-start, a.k.a. slew-limit, the charging of a 220 uF capacitor Cf at a maximum current in the neighbourhood of 300 mA. Cf is a filter cap preceding a further SMPS stage. My plan so far ...
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Control PMOS or NMOS for Soft Start with Variable Voltage Source (Battery or known series string of solar)?
I have a soft start circuit that looks like so:
The load will actually be a synchronous boost/buck converter, and ultimately this could also have an AC source instead of just DC and have a rectifier ...
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Soft-start design and performant with short-circuit test
I am working on a soft-start for a capacitive load. I using module QSB40024S24 to create 24V output. At first, I allowed the output of the module to connect directly to a capacitor array (21.4mF in ...
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Soft start circuit problem
I am currently working on a soft-start circuit. The picture below is my schematic. It worked fine in simulation and even in a real circuit. But after several times, turn on and off the power source (...
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Inrush control transient at power on
I have a circuit with a not-so-small capacitor on the supply and I need to reduce the inrush surge; as a matter of fact the power supply breaks after a while (these cinese supplies are not fun)
I ...
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Why does this oscillator not work with a voltage less than 9 V?
By chance of my research and simulations and various tests, I found the diagram of an oscillator with strange behavior. All the oscillators (quasi) that I have encountered work whatever the supply ...
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TRIAC keeps failing
IMPORTANT UPDATE (Update 6), scroll down to see.
I have been trying to make an AC (air conditioner) soft starter for my home AC unit.
I have built the following circuit and connected it to my AC unit ...
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3 phase controlled soft starter and motor vibration
I want to make a soft starter for 3 phase induction motors. TRs are SCR pairs and ZCs are the zero-cross timing respect to line voltages (400V), not phase voltages (230V). I control the firing angle ...
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Soft Start for AC incandescent lamp
i want to make a soft starter for incandescent lamp.
i have seen some magical dimmer or Russian soft start device which are not available near me.
i found some diagram of the Russian soft start device ...
user284562
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Solid State Relay for Large Inductive Load
I have an old, transformer-based welding machine, which is rated to draw about 70A at 240V, at full output. It uses an electro-mechanical relay (contactor) to energize the main power transformer, and ...
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Soft start for fridge compresser [closed]
I live in an off grid property running on 6 12 V batteries. We have a 2000 W inverter and are trying to get a fridge to run on our system. We have enough power to run it, however the issue I am having ...
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