F1410HS CNC Project with Acorn

[LorenzoRR]

Just checked that my multimeter is crap and provides non-constant shitty values... need to buy another one.
Will repeat the measurements.

[martyscncgarage]

Just checked that my multimeter is crap and provides non-constant shitty values... need to buy another one.
Will repeat the measurements.

That's the one thing I don't cheap out on. I buy Fluke

[LorenzoRR]

Just checked that my multimeter is crap and provides non-constant shitty values... need to buy another one.
Will repeat the measurements.

That's the one thing I don't cheap out on. I buy Fluke

Just ordered a Fluke by Amazon
Arrives tomorrow.

[LorenzoRR]

I have updated the measurements:

1) Voltage in pins CW, CCW and FQ (error acknowledgement -Reset-):

Seems that pin CW, CCW and FQ have 24 volts when:

- Spindle runs CW = Knob selector in FWD
- Spindle runs CCW = Knob selector in REV
- Reset after e-stop = Knob selector in "0"

respectively.

2) Signal 0-10 V is not linear. I have charted voltage readings every 10% of potentiometer %:

Thanks!

[martyscncgarage]

I have updated the measurements:

1) Voltage in pins CW, CCW and FQ (error acknowledgement -Reset-):
2020-05-22_Voltage-measurements.jpg

Seems that pin CW, CCW and FQ have 24 volts when:

- Spindle runs CW = Knob selector in FWD
- Spindle runs CCW = Knob selector in REV
- Reset after e-stop = Knob selector in "0"

respectively.

2) Signal 0-10 V is not linear. I have charted voltage readings every 10% of potentiometer %:
2020-05-22_0-10V-non-linear.jpg


Thanks!

I would agree. Please rerun the speed test and measure the voltage between pins 4 & 5
Do you have a way of tracking the RPM from zero speed to high speed, so we can see the voltages at X RPM?
Marty

[LorenzoRR]

Will use the inductive tachometer I have in my lathe. I think it will work.

Lorenzo

[cncsnw]

What is the relation between commanded RPM (commanded percent speed) and measured analog voltage, if you disconnect the analog wires from the VFD?

If that is linear and on track, but you get distorted results when connected to the VFD, then try adding a 0.1uF capacitor across the analog output, or perhaps this circuit with two capacitors and a resistor:

[LorenzoRR]

Hi,

I was measuring with a low impedance multimeter and it was affecting the measurement itself.

With a normal one, response is perfectly linear, starting from 100 rpm, 0 VDC to 8000 10 VDC.

Also double checked selector voltage w.r.t. CW/CCW/FQ pins and previous conclusions were correct. Final report below:

RPMs are accurate as managed to fit lathe's inductive sensor:

Do you think I still need signal isolator? if Centroid's H8 is stable I would not see the need?

Ready to start bench test I think !

Thanks

Lorenzo

[martyscncgarage]

If it's a true VFD (3 wires feeding the motor?)
Then perhaps you do not need the signal isolator.

Use an output for SpinFwd and an output for SpinRev
Use the generic VFD schematic in the Acorn schematic package. DO make sure you use the relay board

[LorenzoRR]

If it's a true VFD (3 wires feeding the motor?)
Then perhaps you do not need the signal isolator.

Use an output for SpinFwd and an output for SpinRev
Use the generic VFD schematic in the Acorn schematic package. DO make sure you use the relay board

Yes, it is 3-phase 220V, confirmed by supplier.
I will study that layout.
Thanks.
Lorenzo