90V DC Motor Control

[TonysControls]

This is my first time doing any sort of motor controls with PLCs so I am looking for some help determining what kind of equipment I will even need. This is a pretty simple action that needs to be done, I need to be able to control the speed and reverse the direction. I have spent a lot of time reading about this but couldn't find anything that was 100% what I was looking.

This is the motor: https://www.mcmaster.com/6470K61/

I am using a CompactLogix 5380 to try and control this motor.

I'm still unsure if I need to find a power supply that outputs 90V and also have a DC motor driver or if the motor drivers will take 120 VAC from the wall and control and power the motor.

Any help, and especially recommendations for a DIN rail mountable DC motor driver for this 90V motor would be super appreciated.

Thank you

 

[LadderLogic]

You may want to use something like these: https://www.bodine-electric.com/products/dc-controls/ They are powered off 120 VAC and produce adjustable DC output.

There are probably many more on the market, I looked at Bodine Electric because the motor you are buying from MacMaster looks very much like a Bodine one.

 

[Lynx777]

Check this out, https://www.minarikdrives.com/mdpm07-d230-4q-pcm

Most DC drives, including the one above, will handle the voltage conversion from AC to DC.
You would just need a digital output for run & stop and a +/- 10 vdc analog output for speed and direction control.

There are plenty of other DC drive manufactures out there. The one I linked just happens to be one I recently used.

 

[strantor]

I most often encounter KB Drives for these small DC motor applications. Note that KB drives do not have isolated analog inputs. They are 0-10V inputs but they are floating 90V above ground. Couple of considerations for this:
# 1 that harmless 0-10V input can shock you
# 2 your PLC analog output needs to be isolated. Some cards are isolated channel-to-channel but most are only isolated card-to-card, and all the channels of a given card share a common. I recently had to use 4 analog output cards to control 4 of these drives, even though each card had 4 analog outputs (3 unused, each). It would have been cheaper to use signal isolators but time was more important than money in this case and I had the cards on hand.

This is important to consider, and I think it is more or less a universal truth of all these cheap DC drives regardless of brand name, although I can't say for sure as most of my experience is with the KB drives. Maybe Minarik or Bodine or others are different but I doubt it.

 

[kamenges]

Originally posted by strantor:

Note that KB drives do not have isolated analog inputs. They are 0-10V inputs but they are floating 90V above ground.

I'll second that. I let the smoke out of an analog output card early in my career because I missed that point. Incidentally, that one was also KB. And I also believe this is fairly common for the low cost class of drives you will likely be looking at.

Keith

 

[OkiePC]

Another vote for signal isolator. Popping the only free analog output on a critical PLC-5 early in my career was a lesson I haven't forgotten.

"When in doubt, don't let the smoke out."

You can get a panel mount DC drive for that motor at A/D as well as a signal isolator. They have a variety of offerings depending on needs. The least expensive one would require the isolator and and a discrete (contact) for reverse operation:

https://www.automationdirect.com/ad.../high_voltage_(>_50v)_dc_drives/gsd7-120-5cr3

signal isolator:
https://www.automationdirect.com/ad...ers/high_density_signal_conditioners/sc6-2200

Or:
https://www.automationdirect.com/ad...voltage,_current_or_potentiometer_input/fc-33

 

[strantor]

Another vote for signal isolator. Popping the only free analog output on a critical PLC-5 early in my career was a lesson I haven't forgotten.

"When in doubt, don't let the smoke out."

You can get a panel mount DC drive for that motor at A/D as well as a signal isolator. They have a variety of offerings depending on needs. The least expensive one would require the isolator and and a discrete (contact) for reverse operation:

https://www.automationdirect.com/ad.../high_voltage_(>_50v)_dc_drives/gsd7-120-5cr3

signal isolator:
https://www.automationdirect.com/ad...ers/high_density_signal_conditioners/sc6-2200

Or:
https://www.automationdirect.com/ad...voltage,_current_or_potentiometer_input/fc-33

Thanks for posting this; I've never ordered DC drives from AD, didn't even realize they sold any. I will try one next time I have a DC drive project.

Your post prompted me to browse around a little. I don't have time to dig any deeper right now so I'm not sure why this one is cheaper than the one you found, but it is, same ratings, and is compatible with this isolator which also costs half as much. Trade-off is it only takes 4-20mA or 0-5V, no 0-10V or +/-10V.

 

[OkiePC]

Thanks for posting this; I've never ordered DC drives from AD, didn't even realize they sold any. I will try one next time I have a DC drive project.

Your post prompted me to browse around a little. I don't have time to dig any deeper right now so I'm not sure why this one is cheaper than the one you found, but it is, same ratings, and is compatible with this isolator which also costs half as much. Trade-off is it only takes 4-20mA or 0-5V, no 0-10V or +/-10V.

It doesn't have built in reverse, so you would have to have an external reversing switch or contactor arrangement to reverse the motor.

Good find on the signal isolator interface board. I didn't know those existed.

 

[tripstuf2]

I use Dart controllers, inexpensive and easy to get from places like MSC..120v input 90vdc out. Here is a model that is open chassis...Dart Controls
Dart Controls
DC Motor: Open Enclosure, 1 hp, 25 Nameplate RPM-120 & 240V
MSC# 35367549Mfr# 125DV-C-K
Price:$178.79
They have sizes up to 2HP @ 180vdc.