Mitsubishi Vfd - Wiring - Can't Figure It Out.

Okay guys. I'm baaack.

Got it all wired up, and the controls are working (in testing) as expected. However, when i try to turn on the lathe i get about 1/2 inch of rotation and then an E.OV2. So...I removed all the circuitry i built and tried running it directly from the VFD. I checked the manual and it says that E.OV2 is "Regenerative overvoltage trip during constant speed" which is triggering the "Stall Prevention" circuit. Any kind words of wisdom?

FWIW, the motor has 9 black wires, 6 of which (in bundles of 2) were wired to a RPC, the 4th bundle which is comprised of 3 wires was just wire nutted together. When i wired the VFD i took UVW and connected them to the 3 2-wire bundles. I took the ground and connected it to the bundle of 3 wires thinking it was ground....maybe not?
 
Last edited:
Did you set all of the motor and other set up parameters? Sounds like an incorrect setting, maybe.
 
I did set the Frequency to 60 Hz. Other than that i am not sure what to set?
 
There are probably 5 or 6 parameters you have to set. Motor current, motor max RPM, accel, decel times, maybe input and output voltage. Time so sit down with the user manual for a bit . Don't get bogged down in all of the extra stuff, but there are a few things that have to be set up.
 
Okay - RTFM - got it. Although i have to admit that is the worst manual. They don't give you a printed copy so you have to read the PDF, which would normally be okay, except their manual makes you jump from pg 17 to 144 to 54 to 119 to 202 just to figure out what one parameter does. Based on the motor plate (attached) i have set the following params.

1 Max Frq = 90
2 Min Frq = 30
3 Base Frq = 60
7 Accel Time = 15
8 Decel Time= 30
9 Rated Current = 4.8
83 Voltage = 240
154 Surpress Overvoltage Prevention = 11 (per a manual supplement)

Now i get E.ov1
IMG_0459.JPG
 
You might indicate the exact model VFD you have as there are many versions with slightly different program parameters.
The manual is a nightmare of confusion and referencing pages and sections, so clear as mud.
You need to set the motor rated voltage to 230V, although 240V will not harm it.
You need to set the number of poles to 4
Motor capacity may be in amps (4.8) or KW (1.2)
Some ask for RPM at base frequency (1725 RPM).
Acceleration I would set to 5 seconds
Deceleration to 3 seconds (unless it trips with an over voltage when stopping). I would get a generic braking resistor is you have any issues.
There is an applied motor = standard motor
Control method selection = General purpose magnetic flux control
There are other parameters for auto tune and overload settings for the motor.
We can give you some further guidance on other settings as needed.
Mark
 
phew... So much for "simple setup"

I am running a Mitsubishi FR-D720S-100-NA

I reset motor to 230v
Verified that motor capacity asks for Amps (4.8)
Accel and Decel have been reset per your instruction

Param 71 (Thermal Characteristic of the Electronic Thermal Relay Function) is has a default value of "0" which is "Thermal characteristics of a standard motor" but also offers a setting "3" which is "standard motor".. uh huh - thats clear!

It also states : "When General-purpose magnetic flux vector is selected, the motor constants (SF-JR, SF-HR, SF-JRCA, SF-HRCA, etc.) necessary for control are selected as well." but that is not an option...



TIA.
 
Last edited:
I took the ground and connected it to the bundle of 3 wires thinking it was ground....maybe not?

Sorry, I missed that one. 4-5-6 are just connected together, but not to anything else. Ground goes to the ground lug in the motor connection box, normally a green screw, but any screw to the motor frame will do.

1-7, 2-8, 3-9 are connected to U,V,W
 
That was it. Rewired that ground and she fired right up!! Whoooo hoo! I'm cutting chips. A big THANK YOU to Mark and Jim.
 
Back
Top