Even more "Shoestring" electrical questions

Burchtree

Burchtree

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I'm putting together the VDC box for the coming KMG and I had some questions. Anyone have close-up shots of the on/off switch?

Got the 16-guage white/green/black power cord and am trying to figure out how to hook up the on/off through the inline fuse and onto the VDC circuit board.
 
Michael, On the input side of the controler or AC side it should show a ground, and L1 and L2 for your 110 or 220 line voltage.Run your green to ground, white to L1 and use black for the switch and fuse.Use a SPST switch for this and make sure it is rated for the proper amount of amps.Ideally both incoming lines should be fused.Hope this helps.Dave :)
 
Here's a pic of what I got going on. I don't need reverse or anything right now, I'm just concerned with variable speed. I plug it in and all the LEDs light up on the circuit board, but no go on the motor. Don't mind the duct tape and the use of green off the switch (guess it should technically be black).

Any ideas what I'm doing wrong? And what the heck are the two blue leads coming off the motor? One has a female connector and the other male.
 

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Dumb question time: Just to clarify, is that an SCR drive for a DC motor?

If so, and you have four wires coming off your DC motor, then it probably has a wound field. (As opposed to a permanent magnet field) The blue wires would then go to the field connections on your drive. I hate to break it to you, but I don't see field connections on your drive. They are usually labeled F1 and F2.

What is the make/model of your motor and of your drive unit?

Dave
 
I called Surplus Center the techs told me the blue wires were to go to a tach and could just be capped off (if that helps.)
 
Well, that's good news about the blue wires.

Get ahold of a meter and make sure there's DC voltage coming to the motor out of the board, and that it changes as you turn the speed pot.

Are you trying to start off slow, with the speed pot on minimum? If so, it probably won't turn the motor. If you haven't already, try turning the speed pot back and forth full range.

I am running out of ideas - hope something works soon!
Dave
 
Thanks for the help!

Alrighty -- I jacked around with it some more last night and and though it wouldn't turn on when I turned the switch (thought the LEDs would light up), it would turn on when I turned the pot switch. After it was on, it would go as fast or as slow as I wanted. So why won't it just turn on, and why do I have have to jack with the pot switch once it's on to get it running?
 
You mean you can have the pot switch in the middle of it's span before you turn it on and get no output on the drive until you move it off the original setting of the pot switch? Or is the pot switch at "0" when you turn on the drive and then when you ramp the switch up the output follows?

If it's the later then the pot switch may have a mechanical NO at the start of the swing.

If the first, then it may have a PID loop circuit built in, but not likely.
 
The pot is your speed control, if it's all the way down, you won't have any speed. Torque, but no speed.

The tach is for the drive to help it regulate speed, but not all drives need it. Some drives just use armature current instead.

Give me the model number of your drive and I may be able to get you a datasheet on it. I do industrial control systems servicing and repair (we even have a customer in Springfield, GE), so we may have prints for it in our file library. Or, you may be able to download it yourself if it is still an active model for minarik
Minarik Document Page
 
Jim_Linch said:
You mean you can have the pot switch in the middle of it's span before you turn it on and get no output on the drive until you move it off the original setting of the pot switch?
Click to expand...

That is correct. I tried setting the pot at different settings and turning it on, but it still doesn't do anything until I "tune it" by moving it around until it starts up.

I believe this is the page: http://www.minarik.com/PDFs/250-0246.pdf

Of course, that is all foreign to me. Do I need to make adjustments?

(I told you guys I was really inept.) :) I do really appreciate all the help you all have given.
 
Micheal

I took a look at the manual. You may have the minimum speed set too low. There needs to be some power flowing through the motor to magnetize the rotor, before you even try to make it do some work. Try working through the "Calibration" section on page 26. Please read the safety warning on page 26 and take it seriously. The way this drive looks like it was designed, it is likely that the little trimpots are at some lethally high voltage when power is applied to the drive. You are best off if you only make adjustments after the drive has discharged for at least 30 seconds. If you slip with your screwdriver while the power is on, the "magic smoke" may escape from some of the components on the board and the drive have to be repaired or replaced. Sometimes, this can be quite dramatic.

Good luck!

Phil
 
Thank you very much. I noticed that the LEDs kept on shining a bit after I turned it off, so I figured it was storing a mean punch.

I'll give it a gander, and I'll definitely be as safe as I can. :)
 
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