VS40 Carousel Home: Alignment Is Required, Not Reset

The carousel no longer lines up with the tool-change position after the servo-drive battery replacement. Start here: restore the carousel’s mechanical alignment with controlled MPG movement, then establish its reference through 1815. Repeating resets or changing the reference before alignment only records the wrong position.

Stop Trying the Wrong Fixes

Do not start by toggling 1815. That action does not physically align the tool chain. It tells the control how to interpret the current servo position, so using it early can establish a false home.

• Do not keep commanding magazine index moves. The control repeats moves from an incorrect or invalid reference.
• Do not home the machining axes and expect the carousel to recover. Machine-axis reference return does not mechanically establish the magazine station.
• Do not replace the new battery again unless its voltage or connection fails inspection. The battery preserves position data; it does not define the mechanical datum.
• Do not move switches or loosen the carousel mechanism first. A lost reference can look like a mechanical offset even when nothing has shifted.

Identify the Actual Control Configuration

The machine information identifies the control in two ways: Fanuc 18M and a Seicos 18M installation using Fanuc 18iMa hardware. Treat that distinction as a configuration check. Keep relays, axis assignments, and machine-builder ladder functions are installation-specific even when the operator screens look similar.

The documented manual-movement path uses magazine handle select K000.7. Making that keep relay allows the MPG to operate the tool chain when the MPG is placed on the fourth axis.

Before changing anything, confirm all three items:

• The displayed control and machine-builder configuration match the documentation used for recovery.
• K000.7 is the magazine handle-select relay on this machine.
• The fourth-axis MPG selection represents the tool chain, not another installed rotary device.

If those checks fail, that is not an alignment fault. Obtain the machine parameter backup, keep-relay list, and ladder documentation before proceeding.

Prepare the Carousel for Manual Alignment

Clear the spindle, transfer arm, magazine path, and tool pockets from any collision condition. Keep personnel outside the mechanism’s travel area. Manual MPG motion can move the chain immediately once the selection relay and interlocks are satisfied.

• Record the current value of K000.7.
• Record every displayed bit for parameter 1815 before editing it.
• Record which axis column the control associates with the magazine or fourth axis.
• Mark the current carousel position so an unexpected direction is obvious.
• Select the smallest usable MPG increment before enabling magazine movement.

Do not defeat doors, clamps, transfer-arm conditions, or other magazine permissives just to obtain motion. If the MPG command is blocked, inspect the ladder conditions for magazine manual mode and determine which interlock remains false.

Align the Tool Chain with the MPG

1. Place the machine in the operating state required for protected manual magazine movement.
2. Make magazine handle-select keep relay K000.7.
3. Select the fourth axis on the MPG.
4. Apply one small MPG increment and confirm the tool chain moves in the expected direction. Stop immediately if another axis moves.
5. Jog the chain in small increments toward the mechanical tool-change station.
6. Approach the final position from the normal indexing direction. If you overshoot, back away far enough to remove mechanical play and approach again from that direction.
7. Align the pocket or chain station with the machine’s established transfer datum. Use the builder’s alignment marks, locating feature, or service gauge; visual centering alone is not adequate when the transfer mechanism has limited clearance.
8. Stop MPG movement and recheck the pocket identifier against the control’s displayed tool or magazine position.

If no fixed alignment mark or gauge is available, do not invent a centerline. Obtain the VS40 mechanical alignment method before setting the reference.

Commit the Reference Through Parameter 1815

Change 1815 only after the carousel is physically aligned. Parameter 1815 contains axis-specific fields, so editing the entire parameter or the wrong axis column can disturb another axis.

1. Enable parameter writing through the machine’s authorized service procedure.
2. Select the axis field assigned to the carousel or fourth axis.
3. Toggle only the 1815 bit specified by the VS40 parameter procedure or the machine’s known-good parameter record.
4. Perform any reset or controlled restart required by that machine procedure.
5. Restore parameter-writing protection.
6. Return K000.7 to its recorded operating state unless the builder procedure explicitly requires it to remain made.

The evidence identifies parameter 1815, but not its bit designation or required toggle sequence. Read those details from the machine-builder procedure or parameter backup. Guessing the bit risks changing reference behavior for the wrong axis.

Prove Alignment and Position Retention

Test the repair before loading production tools or running an automatic tool change.

1. Confirm the carousel remains centered at the transfer station after leaving MPG mode.
2. Index one pocket away, then command a return to the aligned pocket.
3. Where machine operation permits, index in both directions and compare the final alignment. Direction-dependent error points to backlash, chain tension, coupling, or mechanical wear.
4. Compare the physical pocket number with the control’s displayed magazine position.
5. Run a protected, low-risk tool-change test with the machine prepared to stop before contact.
6. Perform a normal controlled restart and repeat the index-and-return check. Loss of alignment after restart points to an incomplete reference procedure or continuing position-retention trouble.

A single aligned pocket is not enough. Check multiple pockets around the carousel. A constant offset supports a reference error; an offset that changes by pocket requires mechanical inspection.

FAQ