Mitsubishi VFD issue

nuwan

Member
Join Date
Sep 2013
Location
Moratuwa
Posts
30
I have a problem with Mitsubishi f700 22kW [ fr-f740-00470-ec] VFD. When it arrived to our workshop, there was a short circuit between the rectifier outputs. I disassembled it and found there is a carbon deposit between the DC Bus outputs. The IGBT module and the caps were good. After cleaning the carbon it off, I reassembled it.

I tested with a 400v transformer by giving power to two terminals L1 and L2. But now there is a CPU error E.7

According to the manual the fault is "CPU fault - Stops the inverter output if the communication fault of the built-in CPU occurs.
Check point Check for devices producing excess electrical noises around the inverter.
"

How would I be able to solve this ? Please help.
 
Hello:
This error will be generated when the communication between the PLC and the fr-f740-00470-ec and the Mitsubishi PLC is not working. I checked the manual as I am not familiar with this VFD, but I have worked with another product which is from the same family. According to the manual, this device uses something called Mitsubishi Inverter Computer link protocol. If you only apply power but the PLC is not communicating, you will see this E.7, I am almost sure.

http://dl.mitsubishielectric.com/dl/fa/document/manual/inv/ib0600177eng/ib0600177engf.pdf
 
I noticed you said connect L1 & L2 what happened to L3 I believe this needs 3 phases not 2, is that a typo.
Also, I suppose it is possible that what caused the burn may have spiked the electronics i.e. cpu or other electronic component.
 
Hello:
This error will be generated when the communication between the PLC and the fr-f740-00470-ec and the Mitsubishi PLC is not working. I checked the manual as I am not familiar with this VFD, but I have worked with another product which is from the same family. According to the manual, this device uses something called Mitsubishi Inverter Computer link protocol. If you only apply power but the PLC is not communicating, you will see this E.7, I am almost sure.

http://dl.mitsubishielectric.com/dl/fa/document/manual/inv/ib0600177eng/ib0600177engf.pdf

Hi AlfredoQuintero !

Thank you for your answer. This VFD was never used for any communication with a PLC. I believe this has to do something with the EMC noise level. Please let me know your thoughts.

I noticed you said connect L1 & L2 what happened to L3 I believe this needs 3 phases not 2, is that a typo.
Also, I suppose it is possible that what caused the burn may have spiked the electronics i.e. cpu or other electronic component.

Hi parky!

Yes. For some VFDs we can test with only supplying two phases with a 400v o/p step-up transformer. It is a common practice with the repair technicians. If a VFD needs three phases to turn on, you can easily short circuit the remaining phase [L3 in this case] with L1 or L2. Thank you for your answer.

I have attached some photos of the VFD with the error. I really appreciate any help you can provide. Thanks.

1.jpg 2.jpg 3.jpg
 
Hi nuwan. I have been reading the technical documentation of this product and I cannot understand why it is showing E.7 which is poorly defined along with E.5, E.6 and E.CPU as internal CPU communication failure. The product goes to EXT operation at power on and in EXT mode it is not communicating, thus I cannot understand this alarm. Sorry for not being able to provide further assistance.
 
Is the vfd normally connected to a controller? If so has it been connected to the controller to see if the alarm goes away.

Your bench test implies to me that it is not reinstalled within its original system.
 

Similar Topics

Dear members, I'm now working with VFD ( Inverter) from mitsubishi. The spec for the inverter is FR-A520-5.5K ( for 5.5kW motor). The...
Replies
10
Views
3,945
Hey Every one I am trying to set to frequency of vfd to 100z but cant the parameter #125 is the parameter to set the frequency of vfd more than 70...
Replies
6
Views
2,150
Hello Everyone I am trying to establish RS485 communication between Mitsubishi vfd E700 and delta plc DVP20EX00R2 The problem i am facing...
Replies
0
Views
2,446
Hi everyone after a long time!!! I have afew stone cutting machines that are having VFDs upgrades. They all have various S540 models installed...
Replies
7
Views
1,993
Hi Folks... I am considering connecting a braking resistor without a brake unit, to the terminals P/+ and N/-- of this 22kw, F-700 Mitsubishi...
Replies
22
Views
6,183
Back
Top Bottom