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Can AC contactor be used for DC?
tcmtech. It’s pretty common to see higher current rated AC contactors used in lower voltage high current DC circuits. Miller and Lincoln welder Co both have smaller MIG models that use common three phase 60 amp 600 VAC rated contactors as their primary DC side control.
Can you use DC on an AC coil?
You can use AC coils on DC circuits providing you apply enough DC voltage to draw the same amount of current as when operating on AC. It doesn’t care what voltage (AC or DC) is impressed on it as long as the voltage level does not exceed the voltage rating of its magnet wire insulation.
What is the difference between AC contactor and DC contactor?
AC contactor uses grid arc extinguishing device; DC contactor uses magnetic arc extinguishing device. The AC contactor’s starting current is vast, and its maximum operating frequency is about 600 times per hour. In comparison, the maximum operating frequency of the DC contactor is 1200 times per hour.
How does a DC contactor work?
DC contactors are electrical switching devices, similar to a relay. The contactor functions by applying a voltage to the coil, this creates a magnetic field which moves the contacts to the closed position and completes the circuit.
What is the difference between an AC and DC coil?
A Dc relay coil has resistance that limits the dc current. An AC coil relies on its impedance for governing the current. An AC relay will remain contact closed due to mechanical inertia and a little mechanical hysteresis and, the fact that an alternating north and south pole both attract the relay armature.
What happen if DC current passes through a coil and why?
When DC current flows through any coil, it creates its electric & magnetic field. Instead the coil would be like a long piece of wire without much resistance. When the coil is disconnected this magnetic field will collapse. When it collapses a reverse voltage is generated in the coil.
What is contactor and types?
A contactor is an electrical device which is used for switching an electrical circuit on or off. Contactors are most commonly used for controlling electric motors. There are various types of contactors, and each type has its own set of features, capabilities, and applications.
Can a contactor coil be used with DC or AC?
An AC rsted coil will work with AC only. It is designed for and needs AC to develop electromagnet. If supplied with DC, it can act as low resistance psth, and burn out. However , a contactor with AC operated coil can as well have contacts which work or are designed for DC supply .
What kind of voltage do contactors respond to?
I drive them with a short pulse of high voltage, usually about 15 ms and 140% of the rated voltage, followed by a holding voltage about 10% of the rated voltage.The high voltage pulls the contacts in, the lower voltage is enough to hold it in. The contactors respond faster than on AC.
How much is an AC-1 contactor for a 20A circuit?
An AC-1 contactor for 20A is about 40$ and a 20A DC/ 48V and above relay is 200$. Let me check if the welding/ fork-lift guys have 48V rated relay. Cheers man! Lots of golf carts and electric pallet jacks are 24V, many forklifts are 36V, and many forklifts are 48V.
Can a welder use a multi pole contactor?
Yes, it quite commonly done. Many smaller MIG welder power supplies use ordinary multi pole AC power contactors to switch their low voltage high current DC side output power on and off.