I am actually trying to protect the coil here. Yes this is basically an electro magnetic contactor, and the working voltage of the coil is 110v. The contactor works in DC voltage. To protect the coil from surge i am using it as a protection device.
The Contactor will handle slightly inductive load. But i need to restrict the voltage to a maximum of 120v-130v. This is the reason i used the 130v vdr. But i didnot have the knowledge about the same. I have to use the same vdr rc citcuit for space and drawing constraints but what is the more...
Am very sorry, its a varistor. I am attaching a schematic. Am using it as a protection device for a type of relay or contactor to save from the over voltage during turn on and turn off. The working voltage is mainly 110v so i wanted to limit the maximum voltage to a maximum of 130v. Basically a...
I am trying to make a coil suppressor to restrict any voltage above say 130v. It is a simple VDR RC circuit. I am using a resistance of 47ohm, 250v and a capacitor of .1nF 250v a VDR of 130v. But the circuit is not working as expected. Is it because of the voltage spec of resistance and...
Exactly right, sir.
The closing time is faster than required and the opening time is slower than expected.
The coil that we are using is about 450-470 ohms.
We will start with tial and error procedure by increasing the tension of the spring first. The air gap between the contacts also...
Mr. Hardy, Carl thanks for those inputs.
I will try to break it down and be as descriptive as possible. We are actually trying to reverse design and upgrade.
Now about the basic construction, It has Contact Unit, Actuating Solenoid, Arc Chute, Electro magnetic arc blow out coil...
I am trying to make a DC electro magnet coil. The Coil is wound up to the core. And works fine. But I'm not being able to find out the inductance of the coil. The Resistance of Coil R20= 490 ohms. Impedence is 523 Ohms. 110v give .21 amps. Please Help.
The tests are basically conducted on no load basis. The rated current being 50amps. And closed current limit is 250 amps.
Did consider vacuum type. But again, the basic design criteria has to be followed.
Is the braking and opening only dependent on the spring strength or mass? Does alteration...
The tests are basically conducted on no load basis. The rated current being 50amps. And closed current limit is 250 amps.
Did consider vacuum type. But again, the basic design criteria has to be followed.
Is the braking and opening dependent on the spring strength or mass?
Actually I have to work on some set parameters, in which the arc chute is the basic design criteria. Rated voltage being 3000v and max operating voltage 4500v.
Switching frequency is 2 switchings per second.
The main reason for the arc chute is that the arc cools down and produces necessary...
Thank you for those informative inputs. I've been lately out of town, and back again to resume.
Well, i have placed a silver tip in the contacts.
The contactor is working fine. All the high voltage and insulation tests are upto mark except for the Closing and Interrupting Time.
I have to...
I am designing a contactor for both DC and AC mainly for polarity independent circuit-breaker. It has a contactor unit, actuating solenoid, arc chute, Electromagnetic arc blow out coil Auxiliary contacts and base plate. Basically i got stuck in the Time constant measurement, ie the Bracking and...