Who wants to know why more about DC Electronics? Ohms law part 1 and part 2

[Industrial Toys]

Have one that I never used, yet. Part of my Internet link is a 500 foot run of RG6 going through bush up a steep hill. Better to know where a fault is, than dig at the cable through thistles and burdocks. For the device to be of any use at all, you have to know the Velocity of Propagation, for the particular cable.

As a kid, I tried to use armoured 2 pair telephone cable in place of 52 ohm coax which I could not afford. The principle appeared about the same.

My newest DC problem. I have a C.P. Clare stepper relay that is marked 600 ohms. 7350 turns. I have been trying to figure out the voltage of that thing almost as long as I have been alive. I could use it for a load shedding system to put things back on line one at a time. I just tried a PSU that goes up to 135 AC (Nada) and 60 VDC, not a twitch!

How can some relays be 600 ohm and operate well at 24VDC, and this one won't twitch at 60? Sometimes I feel as dumb as I was with that telephone cable!

 

[radios1]

Have one that I never used, yet. Part of my Internet link is a 500 foot run of RG6 going through bush up a steep hill. Better to know where a fault is, than dig at the cable through thistles and burdocks. For the device to be of any use at all, you have to know the Velocity of Propagation, for the particular cable.

As a kid, I tried to use armoured 2 pair telephone cable in place of 52 ohm coax which I could not afford. The principle appeared about the same.

My newest DC problem. I have a C.P. Clare stepper relay that is marked 600 ohms. 7350 turns. I have been trying to figure out the voltage of that thing almost as long as I have been alive. I could use it for a load shedding system to put things back on line one at a time. I just tried a PSU that goes up to 135 AC (Nada) and 60 VDC, not a twitch!

How can some relays be 600 ohm and operate well at 24VDC, and this one won't twitch at 60? Sometimes I feel as dumb as I was with that telephone cable!

60/600=120mA, so if it don't energize with that, maybe the coil is open!. have you checked the coil with an ohmmeter?..

 

[Fuddy1952]

This explains it all!

 

[k0ua]

This explains it all!View attachment 615617

That does work pretty well.

I used to try and use an hydraulic analogy of pressure, flow, and restriction. But then I started to realize that a lot of folks have no inkling of the pressure, flow, restriction and how they are related, so I gave up on that one.

 

[Industrial Toys]

I did try and it read 618 ohms. It has a very stiff armature.

 

[lilranch2001]

Braggert !

 

[k0ua]

Ok so what is voltage? Lets see if this helps some:

 

[radios1]

I did try and it read 618 ohms. It has a very stiff armature.

then you might have to free up the bearing surfaces with silicone oil..

 

[Industrial Toys]

Thanks, but I do believe it is as it should be. It must use a pile of power to pull in.

And todays DC considerations for me. Snubber circuits for DC switches. DC does seem somewhat painful in a number of regards.

 

[radios1]

Thanks, but I do believe it is as it should be. It must use a pile of power to pull in.

And todays DC considerations for me. Snubber circuits for DC switches. DC does seem somewhat painful in a number of regards.

it should work on 24VDC IF you have enough current to drive it. maybe your power supplies can't deliver 2 Amps or so. if you can see the gauge of the wire it's wound with, you can figure out the amperage that the coil may need.. as far as snubber circuits for DC switches go, a simple explanation and fix is here. Snubber Circuit for DC Power Switch - RC Groups