Questions tagged [contactor]
A contactor, like a relay, is an electrically controlled switch. Contactors generally have higher voltage and current ratings than relays, but the ratings overlap with no specific dividing line. Contactors are intended to control the power supplied to motors, electrical heaters, groups of lights and other loads that require an undefined level of "high power." The word "contactor" is essentially defined by its use in product literature.
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Traffic light control in VPS
I have to realise a traffic light control with hard-wired programmed logic controller (relays & contactors time-delayed relay) and I have already prepared something.
Problem/question:
The problem ...
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Contactor lifespan if it always on 24 hours/7 days?
I'm using a contactor Mitsubishi S-T65 to protect phase loss. Can the coil of the contactor last for a long time if it always ON state (lifespan of the coil)?
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wiring of 4 position rotary switch (new)
As the title points out, I am needing to wire up an operational selector switch for connecting 120V supply to 2 different outputs. Let's call them 'Vibrator A' and 'Vibrator B'. The switch needs to ...
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Why are pre-charge contactors rated at such high current?
I understand how pre-charge works and the reasons for it.
What I don't understand is why pre-charge contactors are rated at tens or hundreds of A?
The pre-charge resistor limits the current, so even ...
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Making a SPDT switch using MOSFET
I need to drive 2 DC contactors similar to a SPDT relay.
I am using Pico Pi as my controller to drive the MOSFETs, and the MOSFET turn on and allow 15V (Relay+-) to drive the contactors.
Serial ...
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ESP32 Freezing Due to Contactor Noise
I'm working on a temperature controller circuit that uses an ESP32 to activate a relay based on temperature readings from sensors. This relay, in turn, controls a contactor.
I've encountered an issue ...
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Managing 24vdc inductive loads going to shared connector
Here's my dilemma - I need to design controls for a robot with a tool changer that picks up 3 different end of arm tools, each tool has a different 24vdc motor on it with rated standstill currents of ...
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Contactor drive PCB - MCU cuts out when closing contactor occasionally
I have a PCB that I am currently supplying 12V which has control of multiple contactors (12V coils with built in economizer so a set voltage should be all that is needed). The board closes all 5 ...
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Switchover Contactor Logic
The contactor logic in the image is for a switchover power supply (from Grid power to PV inverter EPS/UPS output):
The idea is that when there is a grid fault, then T1 changes state. This causes K1 (...
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Ground Switching Relay, 400A
Can a three pole Contactor Relay be used for simply switching Ground? I am trying to reverse the polarity of a welding unit and would need to be able to command essentially two relays to open and ...
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How to limit the effect of Contactors noise on the electronic circuits?
I have designed an electronic circuit that is used to switch 8 relays in certain circumstances (like 8 times in a minute). Then these relays switch on and off the contactors connected to AC electric ...
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Problem to control contactor 380 V coil with TRIAC
I have this schematic using TRIAC BT136 600E, and MOC3023.
I want to control a contactor with a coil voltage of 380 V. The problem is that the TRIAC works without receiving a command from me, so it ...
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Removing turns from a relay coil to make it work on a lower voltage?
I have a piece of machinery that was moved from a building with 240 V to a building with 208 V and all is well but the contactors don't seem to pull in all the way. Could I remove enough turns from ...
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How do I read the specifications on this DC contactor?
This is a solenoid from an Italian made marine windlass.
Could you please help me understand the specifications written on it?
From what I know, the coil and connector is 12V because that is the ...
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Can I use a 30A+ PCB relay to drive an AC Motor instead of a DIN Rail Contactor?
I have a project that involves a microcontroller switching on and off an AC motor (water pump) of no more than 1hp. I found these interesting contactors on aliexpress but I was wondering if I can ...
