Working documentation
This page is generated from the project's working notes. It records a real retrofit in progress, corrections included. Anything marked 🔴 or ⚠️ is unresolved or carries a caveat - read those before acting.
The spindle and its inverter - the complete interface¶
2 September 2026. Read from wiring diagram sheet 5, INVERTER (drawn by Z.C., not F.S.). This supersedes the reference table in CLAUDE.md §9, which was worked out for the Masso plan and lists parameters rather than wiring.
Drive: Yaskawa VS-606V7CC 47P5, 7.5 kW, part 025YAS0015.
Motor: HSD M200 electrospindle, 8 kW, 24,000 RPM, connector -AM-PM 999COB0026 CONN. MOTORE HSD.
Control terminal wiring¶
| Terminal | Sheet label | Wired to |
|---|---|---|
FR |
SPEED REF 0-10V |
-R6 divider network (330 kohm and 2.5 kohm), fed from CONN.S pins 15 and 8, conductors marrone and bianco, referenced to MASSA C.N. |
FS |
+12V 20mA |
-R6 |
FC, COM |
-R6, wires 23 and 24 |
|
SC |
COM |
-C 32, -STRI |
S1 |
FWD RUN/STOP |
wire A221, from 25.5 |
S2 |
REV RUN/STOP |
wire A222, from 25.6 |
S3 |
EXT. FAULT |
wire 56, via -QFRI contact |
S4 |
RESET |
wire 58, via -SB15 |
P1, PC |
RUNNING photocoupler out |
wire 931 to -OPT1 NPN-PNP converter, then E130 to 19.1 |
P2, PC |
ZERO SPEED photocoupler out |
wire 930, to 6.5 |
MA, MB, MC |
DEFECTIVE CONTACT OUT |
wires 19 and 20, to 13.8 |
AM, AC |
ANALOG OUT |
monitor output |
L1,L2,L3,E |
POWER SUPPLY |
via -KMI, from -QFINV (17-23 A, set 20 A) |
B1, B2 |
BRAKE RESISTOR UNIT |
via -QFRI (6-10 A, set 6.5 A) to -R2, 30 ohm 1300 W |
U,V,W |
MOTOR |
through -L1 common-mode choke (3 turns), then 4X2.5 sch screened cable, U3/V3/W3 to 6.0 |
🔴 The analog speed reference¶
-R6 is the SPINDLE kit from Tecnos (025TEC0027, KIT SPINDLE LUNGO + CAVI, sheet 5.1). It is a resistor divider plus cable that takes the CNC's analog output and conditions it for the VFD's FR 0-10 V input, with FS (+12 V, 20 mA) as the reference rail.
The CNC end arrives on CONN.S, pins 15 and 8, brown and white, with MASSA C.N. as the ground.
That identifies the fourth 15-pin D-sub in the device list: CONN.S (025ZAN0020, CONNETTORE VASCHETTA 15PIN MASCHIO, sheet 5.8) is the spindle connector, alongside CONN.X, CONN.Y and CONN.Z for the axes.
✅ Resolved 2 Sep 2026 - R6 is a spindle speed override¶
Read from a zoom of the -R6 block plus SGM page 5.
-R6 is a 2.5 kohm potentiometer in series with a 330 kohm resistor, mounted in the pendant, feeding the VFD's FC / FR / FS on wires 23 and 24 plus the bianco and marrone conductors. The CNC's analog pair arrives from CONN.S pins 8 (bianco) and 15 (marrone) on -R6:1 and -R6:4.
The ratio settles it. A 2.5 kohm pot in series with 330 kohm across FS (+12 V) would put roughly 90 mV at the wiper - nowhere near the 0-10 V that FR expects. So the +12 V path cannot be the speed source. The CNC's analog output is the source, and R6 scales it.
✅ R6 is a spindle speed override on the CNC's command, the exact counterpart of FR1 on the feed. LinuxCNC's S word will control spindle speed.
⚠️ One measurement confirms it whenever the machine next runs: with a known S commanded, measure FR to FC at the VFD while turning R6 end to end. If the voltage tracks the pot, it is an override.
For the retrofit: the VFD wants 0-10 V on FR against FC. A Mesa analog output is +/-10 V. The R6 network can be kept (retaining the manual override, which is a genuinely useful feature) or bypassed and FR driven directly. Either way, check against the VFD's n003/n004 settings before connecting.
Three cross-references that confirm the I/O map¶
The sheet's own wire references decode against MW310.EQU:
| Drawing reference | Decodes to | MW310.EQU |
|---|---|---|
A221 from 25.5 |
Sheet 25 = UF3, point 5 = OF.21 |
OF_MARCIA_INVERTER ("INVERTER 1 ON") ✅ |
A222 from 25.6 |
Sheet 25 = UF3, point 6 = OF.22 |
OF_INV_INVERTER ✅ |
E130 to 19.1 |
Sheet 19 = IF4, point 1 = IF.25 |
IF_VEL_RAGG ("INVERTER 1 ON") ✅ |
AUS n = OF.n is proven by this sheet, independently of the output sheets themselves. Combined with the EIN n = IF.n proof from sheet 16, the whole symbolic map now transfers to physical terminals with no toggling and no LED photography.
🔴 A VFD fault trips the emergency chain¶
MA/MB/MC, the inverter's fault relay, runs on wires 19 and 20 to 13.8, which is relay -KA4. Sheet 16 shows KA4's contact feeding EIN8, the EMERGENZA TERMICI input (IF.8).
So an inverter fault drops the emergency chain in hardware. This is a real interlock and it must survive the retrofit.
🔴 Sheet 6 - the spindle motor contactor and the ZERO SPEED interlock¶
Sheet 6, RESET PANTOGRAFI, carries the motor itself:
-M200,PANTOGRAFO 1 C.U./ROUTING MOTOR, 8 kW, 18 A, 24000 g/min - the HSD electrospindle. Fed from the inverter outputU3/V3/W3plus screen, through-KM200, to=BM+X5terminals-PM 4/6/8.-MV200,VENT. PANT. 1- the spindle cooling fan, single phase on-X5 15and-X5 16.
The contactor coil circuit:
OF.48 (wire 42, from 28.8) -> -OPT2 solid-state relay -> 105 -> KM200 aux 13/14 -> 106 -> KM200 coil -> wire 3
^
OPT2 input: wire 14 and wire 930
930 = the inverter's ZERO SPEED output (from 5.1)
KM200 is a mechanically latched contactor with separate set and reset coils (Siemens 3TF3500 with a 3TX4090-0GF3 latch). Sheet 28 shows OF.48 driving the set coil (A1/A2) through wire A248 from rail 2A. Sheet 6 shows the reset path (E1/E2) running through -OPT2, whose input is the inverter's ZERO SPEED.
So OF.48 closes the contactor on command, and it only opens once the inverter reports zero speed. That is the correct direction for the interlock: it prevents breaking an 8 kW motor circuit under load.
That answers what ZERO SPEED (wire 930) is for: it is not a PLC input, it is a hardware interlock stopping an 8 kW motor contactor from making or breaking under load. It appears nowhere in MW310.PLC, so it would have been invisible to anyone working from the software alone.
🔴 This interlock must be reproduced. Under LinuxCNC, OF.48 still switches KM200, but the zero-speed gate has to stay in hardware.
It also confirms AUS n = OF.n a third time: 42/28.8 is sheet 28 (UF6) column 8, which is OF.48.
What the retrofit needs from this sheet¶
| Signal | Direction | Where it goes now | Retrofit |
|---|---|---|---|
| Speed reference | out | CONN.S 15/8 to -R6 to FR |
Mesa analog output, via or around -R6 |
| Run forward | out | OF.21 via UF3 |
Mesa output on the ribbon |
| Run reverse | out | OF.22 via UF3 |
Mesa output on the ribbon |
| At speed / running | in | P1 via -OPT1 to IF.25 |
Mesa input on the ribbon |
| Zero speed | in | P2, wire 930, to -OPT2 |
Not a PLC input - a hardware gate on the KM200 coil. Keep it |
| Drive fault | in | MA/MB/MC to KA4 to IF.8 |
Leave hardwired |
| Contactor engaged | in | KMI aux to IF.16 |
Mesa input on the ribbon |
| Spindle contactor | out | OF.48 via UF6, gated by -OPT2 | Mesa output on the ribbon, gate stays hardwired |
Related¶
device-list.md--R6,-R2,-U1,CONN.Spart numberspower-distribution.md- the supply chain feeding the inverterCLAUDE.md§9 - VFD parameter settings for external control (n003,n004,n011,SW2)