Modbus RTU to TECO EQ7

[OkiePC]

Anyone have some info for how to control a TECO EQ7 series VFD via Modbus RTU?

We originally installed a pair of Yaskawa GA800s at the remote site and one of them failed. A competitor was $200 cheaper and installed a TECO EQ7, so now they're paying us $200 an hour to make it work with the existing Modbus RTU PLC in control.

I think I gleaned from some of the worst manuals ever written where to write the speed command and control word in this drive (not yet tested) and now I would like to know how to monitor some basic operational data like output frequency and amps.

Both my read and write MSGs are completing successfully in a Micrologix 1100, but the data I am reading may not be useful and as yet is unlabeled in my PLC code.

I am writing to Holding Register 41798 the speed reference as Hz x 10 and the command word to 41799

I am reading 14 words starting with Holding Register 42055 after parsing an example from a Fuji Manual using this handy tool https://rapidscada.net/modbus/

We were first told this was a TECO Frenic MEGA series, but my partner who's on site sent a pic that makes no mention of FUJI, and my quest for useful manuals only made me curse the writers of the few I found.

 

[OkiePC]

So far, here is what I have learned by trial and error where HR means holding register and is "1" based from my Micrologix 1100:

TECO EQ7
HR41798 - Speed Reference (Hz x 100)
HR41799 - Command Word where:
Bit 0 = Run FWD
Bit 1 = Run REV
Still need to figure out the rest of these bits, especially Fault Reset if available.

HR42055 - Output Frequency (unscaled, Multiply by 0.003 to get Hz)
HR42058 - Frequency Reference (Hz x 100)
HR42063 - Bit 0 seems to correlate with VFD running.

 

[Steve Bailey]

Fuji drives are sold under several brands. Assuming the TECO is indeed a Fuji drive, I doubt if they would change much among the different brands.
I found this Modbus mapping guide.
https://americas.fujielectric.com/w...NIC-Ace-Modbus-Communications-FECA-AN-183.pdf

Your examples:
Modbus 41798 corresponds to hex 0706 which is parameter group S, offset 06
Modbus 41799 would be parameter S07

Modbus 42055 corresponds to hex 0807 which is parameter group M, offset 07
Modbus 42058 would be parameter M10
Modbus 42063 would be parameter M15

Hope that helps.

 

[OkiePC]

Fuji drives are sold under several brands. Assuming the TECO is indeed a Fuji drive, I doubt if they would change much among the different brands.
I found this Modbus mapping guide.
https://americas.fujielectric.com/w...NIC-Ace-Modbus-Communications-FECA-AN-183.pdf

Your examples:
Modbus 41798 corresponds to hex 0706 which is parameter group S, offset 06
Modbus 41799 would be parameter S07

Modbus 42055 corresponds to hex 0807 which is parameter group M, offset 07
Modbus 42058 would be parameter M10
Modbus 42063 would be parameter M15

Hope that helps.

Yes, that helps quite a bit! There is even a breakdown of the control word in that pdf. I really appreciate it Steve!