Wiring question: Wabeco VFD to 7i76ED

Hi there! I hope you’re doing well.

Before turning on the power, I would like to ask for a sanity check.

Wabeco VFD:

• Pin 14 (start) is connected to +24V
• Pin 13 (FQ) - no idea - maybe GND or -24V ?
• Pin 9 (M CW) - starts spindle in a clockwise rotation.
• Pin 10 (MCCW) - starts spindle in a counterclockwise rotation.

• Pin 3 (An 10V) - outputs 10V
• Pin 3 (An In) - analogue input 0 to 10V
• Pin 3 (An Gnd) - GND

Mesa 7i76ED
From the manual: SPINDLE ISOLATED OUTPUTS
The 7I76E provides 2 isolated outputs for use for spindle direction control, and spindle enable. These outputs are OPTO coupler Darlington transistors. They are all isolated from one another so can be used for pull up or pull-down individually. They will switch a maximum of 50 mA at 0 to 100 VDC. The SPINENA output is special as it uses the same signal that enables the analog output. When the analog output is enabled, the SPINENA OPTO output is on.

And if I understand correctly, for clockwise rotation, I only need to enable analog output and it will turn on spindle in clockwise rotation.

And if +24V is connected to SPINDLE_DIR+, and SPINDLE_DIR is switched ON, SPINDLE_DIR- will output +24V signal, turning on spindle in counterclockwise rotation?

However I don't understand how I can turn off SPINDLE_ENA and keep analog output enabled? Otherwise both SPINDLE_DIR and SPINDEL_ENA output +24V.

For the reference, I included wiring diagram for CSMIO-IP/M - its realized using two relays. Also analog wiring, from the milling machine is included.

No, that's not quite right. SPINDLE_ENA is just that. It enables the spindle drive, meaning it is activated whenever the spindle is commanded to turn either CW or CCW. Many drives have an enable input.
In your case you will need a relay that switches the enable signal to either the CW or CCW input of your VFD depending on the SPINDLE_DIR signal. So SPINDLE_DIR to A1 of the relay GND to A2, SPINDLE_ENA to the COM, MCCW to NC and MCW to NO of the contact

[edit]
And yes SPINDLE_DIR+ and SPINDLE_ENA+ go to +24V and the SPINDLE_...- terminal outputs the 24V if the respective signal turns on.
Analog output is correct as suggested

Thank you for the reply. Due to constrains in the control cabinet I would rather avoid using relay.

Is it correct that this can be implemented using SPINx1 PWM from MESA? Looks like it has separate Enable, CW and CCW as well as 0-10V.

Do you have a drive manual? Its often possible to program the VFD to accept ENA/DIR
rather than CW/CCW

If not, you can use 2 field outputs to drive the CW and CCW pins (this would require
connecting the field power common to the Wabeco ground pins)

Hm, I guess. I wasn't aware of that board at all. So where are you going to get the TTL level outputs from?
Seems a bit strange that you feel you don't have room for a 2$ mini relay or 12$ relay coupler that takes 5mm on your DIN rail but enough space for a 24$ board that is much larger.

PCW wrote:

Do you have a drive manual? Its often possible to program the VFD to accept ENA/DIR
rather than CW/CCW

Manual is quite limited and its not user serviceable VFD so I don't think I can manage to do that.
Link to PDF of the english manual .

If not, you can use 2 field outputs to drive the CW and CCW pins (this would require
connecting the field power common to the Wabeco ground pins)

Yes I was also thinking about doing it and I'm sure it will work great - however I assume that replacement of the VFD is close to 1000€ - so I would rather not risk it.

Not sure why you think this would be a risk,
The CW/CCW inputs accept 24V input signals

Aciera wrote:

Hm, I guess. I wasn't aware of that board at all. So where are you going to get the TTL level outputs from?
Seems a bit strange that you feel you don't have room for a 2$ mini relay or 12$ relay coupler that takes 5mm on your DIN rail but enough space for a 24$ board that is much larger.

Yes I see how it can look strange. I'm going to convert 3 x Wabeco machines (2 mill and one lathe) with same VFD. So if combination of 7I96 and SPINx1 solves the task, combination would be cheaper then one 7i76ED + relay.

PCW wrote:

Not sure why you think this would be a risk,
The CW/CCW inputs accept 24V input signals

I only think that, because from the factory both manual and CNC versions of the Wabeco machines, all source 24V and 10V from the VFD and keep it isolated from the rest of the electronics. That is even when in CNC version, they have 24V logic in the controller and it would have saved some wiring.

Thanks for all the input! I will start with relay and after I get it running I can try it out with direct signals on the next machine.