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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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 ...
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Shutdown circuit of an EV gokart
My student project team is planning to build an EV gokart. It's supposed to have a shutdown circuit/kill switches. I was planning to implement a DC contactor/high power relay to connect/disconnect the ...
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Choosing Contactors for an EV Battery Pack
I’m designing a battery pack and am uncertain about which contactor to select. Many electric vehicles (EVs) use three contactors: one each in the positive terminal, negative terminal, and precharge ...
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How much voltage can a contactor withstand?
I tried searching, but unfortunately did not find an answer. Given a typical 24V AC (or DC) contactor, how much voltage can the contactor control circuit withstand? Will it be damaged by mains ...
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How can I wire a relay or contactor to an elapsed time meter?
For a DIY project, I want to run the tools in my workshop through a special receptacle in which I have connected an elapsed time meter to be triggered when the tool (e.g. drill, saw, etc.) runs. To ...
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How to fix arcing in the contactor in this circuit
I am building the switching circuit using contactor to switch 300A over the contacts. My circuit is below:
When I run the circuit, the current is switching but I see arcing. See the scope below:
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Contactor circuit where MOSFET fails short
The following circuit has been designed to drive a contactor. In addition to the primary relay the contactor has a secondary auxiliary (AUX) relay that can be used to latch the contactor on.
The ...
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NEMA Coil "Sealed Current"
I am trying to select a relay to interface between a temperature controller output and a NEMA size 4 120VAC contactor coil. According to the NEMA spec, a 120VAC, size 4 has a 8.3A inrush current and ...
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What typical percentage current is required to hold a standard non-latching reed relay/contactor shut?
https://www.solarteam.nl/contactor-economizer has a nice description of a PWM approach to minimizing current consumption in a relay, once the relay is turned on. Presumably, and I might be wrong in my ...
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3-phase weld detection circuit
I have heard this concept of a relay weld detection circuit, which is used to detect if the relay contacts are welded are not.
In the EV charge controller that I am planning to design now, there is a ...
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How to detect the break over voltage for a contactor
I want to determine at what voltage will a contactor fail.
My idea was to either send an impulse or vary the AC power across a contactor. The contractor will be in the open state the entire time. ...
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Conditionally switching 3-phase motor direction using only one contactor
I am creating a schematic for my machine which is supposed to do the following with the push of a button. All motors are three-phase AC motors.
Run Motor 1 CW until it hits its right limit switch.
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