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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Switching 400V motor with 5V
I'am trying to make an automatic irrigation system using an Arduino, a moisture meter and a water pump.
The issue is that I can't figure out whether there is some relay/contactor type component that ...
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Contactor: when and how to use it
I hope my question is not too stupid.
I'm controlling a brushed 48V 50A motor with a motor controller and I use two gel batteries as a power supply.
I would like to use a low power signal to switch ...
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What is the max current of this contactor? CDC65-24
I'm attempting to power a 50kW DC Fast Charger with 3 phase 277/480V. It needs ~55kW which is 66A per phase. I'm trying to find a contactor. This one is CDC65-24. It is a 3 pole, 100A continuous. ...
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Two Switches to Control a Pump
I have a water tank that I want to fill up with a well. I have a float switch at the top of the tank and another float switch in the middle of the tank. What I want to do is have the pump only turn on ...
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Vacuum Contactor Wiring Diagrams
In reviewing the following wiring schematics for a vacuum contactor, I can't wrap my head around why things are the way they are.
Source > Downloads > Catalogues
Wiring Diagram #1, Size 4 Contactor
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How to connect voltage protection relay to contactor?
Could you help me connect a voltage protection relay (VPR) to a contactor? I'm not sure how to connect the relay output terminals (NO, NC, COM, etc.) to contactor control terminals A1 and A2 in the ...
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Digital control of contactors
We are trying to control a bunch of 3 phase contactors using an HMI. The contactors' coils are activated by two lines of the 240V 3 phase source (L1 and L2).
We are trying to figure out if the ...
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Can a contactor be used as a temporal logic bit as in PLC?
I want to design a control logic circuit using relay logic. I want to have a bit as a marker as in PLC. Can I use a contactor for this function and then use auxiliary coils as a latch as in PLCs.
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Which suppresor device will be use for 2pole AC contactor 240v coil voltage in coil as well as contact side?
I need an AC contactor for a 1 hp motor. For the contactor safety I'm goint to use the suppression device on the both coil and contact side. Please suggest me which suppressor device will be use!
I ...
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How Does Line Frequency Affect Coils of a Contactor?
I am using a generator as my source voltage, which produces 240VAC @ 240Hz. I was planning to use the following contactor from TE: CONTACTOR 4PST 40A 240V
In the datasheet it says this contactor's ...
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What lubricant is suitable for switch contact?
I have this expensive DPDT switch (20A 250V 2hp) which the only problem is dirty encumbered inside. The encumbrance is made of carbonized material and some kind of wax and dirty electrical contacts. ...
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Auxiliary contacts on contactor to power solenoid valve
I'm just trying to introduce cold water in to industrial shredder.
Connected cold water supply to machine. That's not good because when I forget to turn off water it will overflow. I have not seen ...
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Why are contactor coils connected to two different safety relay outputs?
When looking through a manual for a safety relay, I began to wonder why the coils of the load contactors (K3 and K4 on pages 14-15) are always connected to two different NO contacts of the safety ...
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Are three-phase contactors rated per pole or in total?
Are three-phase contactors rated per pole or in total? For example, have a look at this datasheet for a random three-phase contactor: datasheet
In the datasheet it says that for AC-3 loads (1) the ...
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Switching a power contactor from an arduino / raspberry
I'd like to switch a power contactor (such as this one : https://www.legrand.fr/pro/catalogue/31925-bipolaires-250-v/contacteur-de-puissance-cx3-bobine-230v-sans-commande-manuelle-2p-250v-25a-contact-...
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CC12 Contactor is Confusing
I am attempting to use this relay, the CC12, to turn the 120VAC power to a motor/motor controller on and off using a 24VDC signal (These voltages are specified in the datasheet.), and I've gotten ...
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IGBT contactor design
I found this circuit in an older post. I was thinking about using this in place of a contactor to break under load. The load would be at 500V 300A DC. There would be overcurrent protection in line ...
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Controlling 2-pole contactor using Arduino
I am working with Packard C230C contactor to develop own EVSE. For a simple start i just want to toggle contactor using Arduino. OpenEVSE is already doing it. Just want to know how do they do it and ...
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Contactor/relay rating for bypass function of soft start circuit
I am designing a soft start circuit for a 70KVA, 70A, 480/230 delta/star transformer, since the fuses kept blowing without.
I've been using 3 NTC thermistors rated for 80A in series with the lines ...
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Automatic cut mains power on a thunderstorm
I am a software engineer with only a basic experience with electric/electronic engineering.
I live in a rural area subject to thunderstorms, my house is the end of the line from street poles. It's ...
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Industrial contactor frequency influence
I'm thinking of using industrial motor contactors at the output of a 3-phase electrical generator.
An example here : CONTACTOR DATASHEET
The only difference / problem is that the electrical ...
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About Contactor Lifespan
Newbie here regarding contactors and relays, i had this contactor datasheet https://www.gavazzionline.com/pdf/CC50-CC65.pdf. I'm trying to identify how long the contactor would last and I find the ...
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Contactor's Coil Current
YuCo YC-CN402-24V CN-PBC402-24V DEFINITE PURPOSE CONTACTOR with a Packard PF42440 Control Transformer Class II Foot Mount 40VA 24V to activate the 2vac coil. The circuit is a 220v 20amp motor. My ...
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Problem in star delta starter in air compressor
I am a beginner in electrical engineering. I am trying to understand how motors are connected in a star and delta system.
I studied the star delta starter from this link. It describes the connection ...
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Which relay will last the longest?
I'd like to control a 20 amp, 240 volt AC resistive load with a heavy duty contactor.
The contactor I have is a Siemens 3TX7130-0DB03 rated for 30 amps, and DPDT. I was originally going to switch ...
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Starting (inrush) current of a resistor (heater)
We are going to purchase a 48kW electric drying oven.
As we know the AC motors have big starting current and a special starting equipment is needed - Star-delta, soft-starter, inverter and etc.
What ...
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Can I operate a 120VAC contactor with a DC power supply
If yes, What would be the voltage and amperage for DC to operate the 120 VAC contactor?
And, Can I connect two contactors in parallel, and actuate both using DC ?
I need it for a project, where I can'...
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Contactor vs Relay
As known, contactor is used to switch higher capacity than relay. But there some relays can switch high current too, such as, some power relays can switch current beyond 100A, and there are contactors ...
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Interface submersible water pump with microcontroller using contactor relay
I am making a automatic water level controller for my home. I am using a MCU to turn ON/OFF submersible water pumps using a float switch to detect water level in overhead tank.
This pump has a start ...
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Trailing edge dimmer to activate relay/contactor
I would like to take the 240V feed from a trailing edge dimmer that is driving LED lamps and use it also to activate a contactor or relay. This would in turn run a 230V fan.
(Reason: want to have a ...
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Using regulator capacitor bank for a motor
I want to use a regulator capacitor bank in a small facility that has a machine so based on the power factor it insert the capacitors. Each 30 seconds the motor power factor is 0.4 and for 10 seconds ...
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switching device for motor
This query is from my project on automatic motor switching of water tank. My question is that what should be the rating of switching device(relay or contactor) for single phase induction motor (2hp 8A ...
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Suggestions on how to control a 1000W DC motor
I would like to find out the best solution to safely control two 1000W DC brushed motors by using a atmega328p.
In particular, the DC motors are rated: 1000W, 50A, 24V, 2400 RPM.
I have a radio ...
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Main contactor of star delta motor starter
Why do some control circuits of star delta starter use two normally open auxiliary contacts of the main contactor and others use one?
To me only one normally open should be enough.
Can a contactor ...
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can contactor, water level sensor and heater all live in parallel on the same circuit
I want to connect my 3000w (220v) water heating element to a 220v water level sensor Automático de Nível so that the heating element won't turn on when there is no water present.
But the level sensor ...
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Automatic transfer switch VS Using a Reversing Contactor with Circuit Protection
We have a an industrial control system that utilizes a 480VAC 3 phase 10 Amp service. For redundancy reasons, we wanted to add an automatic transfer switch to the system to switch between two ...
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Mechanical Contactor for High Voltage DC - Substitute with Semiconductor
To switch 1kV DC at 5A, I usually use a mechanical contactor (<- Wikipedia) that switches both highside and lowside of a resistive load.
Any suggestions on a semiconductor (or non-mechanical part) ...
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Contactor control circuit overvoltage
I have a 12VAC-controlled contactor (ESB 20-20, rated for 12V @50Hz), and a 220/12 transformer that I intend to connect to the contactor. Unfortunately, rather than 12V, the transformer outputs 14V (...
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Correct design for large contactor circuit?
After some advice here I'm wondering if this is the correct design of my circuit.
I'm now using a SSR as the control device to the contactor. The diode, I believe, should not only protect the SSR ...
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Relay/Contactor for 30A inrush, 250mA steady
I'm struggling to find any relay or contactor even close to the specs I need, and I've contacted many manufacturers. This is controlling a large contactor, so draws a 30A 24DC inrush current. It then ...
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Using capacitors to supply peak current
I hope this thread is allowed. Based upon my previous topic, which turned out to be the exact opposite of what I needed to accomplish, I have a few questions.
I have a 240W 24V Supply: https://www.us....
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Suppressing contactor coil inrush, is this possible?
http://www.kvc.com.my/EnterpriseChannel/SharedResources/Datasheet/0/?ProductId=1000066755&Filename=SCHNEIDER-LX4-FH024.pdf
I am trying to operate a 24VDC coil with an inrush of approximately 30A, ...
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What is "x Us" in a contactor coil specification?
I have a data sheet that gives the coil pickup voltage as "0.85…1.1 x Us] and coil dropout voltage as "0.3…0.6 x Us".
I am assuming that Us refers to the nominal or specified coil voltage, but why is ...
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How to detect a plug is connected to a socket
I have a plug and socket. Before I turn on the power supply from a contactor, I need to detect if the plug is connected to the socket via a microcontroller. Any ideas on how to do this?
The plug I am ...
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Using a Contactor or Relay to switch between two DC power sources?
I want to power a motor with a battery, however the complication arises as I want to have two power sources and be able to switch between them. The context of this problem is for an electric vehicle. ...
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