VMC - Pallet Pool - Troubleshooting Guide

Introduction

1

There are differences between the UMC/EC Pallet Pool and the VMC Pallet Pool, please refer to this troubleshooting guide for issues regarding the VMC Pallet Pool machines.

The corresponding pallet pool option can be installed on the following machine models:

VF-2YT, VF-2SSYT, VM-2
- 3 Station Pallet Pool
- 6 Station Pallet Pool
VF-4, VF-4SS
- 5 Station Pallet Pool

The Next Generation software on the machine must be version 100.22.000.1010 or higher.

The VMC Pallet Pool option is not field installable.

The Pallet Pool has 2 servo axes. The PR axis rotates the Pallet Pool saddle and the PS axis extends and retracts the Pallet Pool saddle to load/unload the pallets.

Refer to the Pallet Pool - VMC/HMC Installation - Haas Service Manual procedure for details on how to install a VMC pallet pool.

Pallet Pool

Emergency Stop
Pallet Ready Button
Load Station Doors
Load Station
Air Gun
Drip Tray

Sensors

Receiver Clamp
Receiver Unclamp

3. PP Load Station Door Micro Switches

4. PP Pallet Slide Home Switch

Symptom Table

Symptom	Possible Cause	Corrective Action
Alarm 15.108 AXIS SERVO OVERLOAD Alarm 15.103 AXIS SERVO ERROR TOO LARGE	Binding Transmission	The amplifier could be having an issue driving the motor. If you have this problem, please contact our service department.
After zero returning the PS or PR axis, the following alarms are generated: Alarm 15.103 AXIS SERVO ERROR TOO LARGE Alarm 16.103 AXIS SERVO ERROR TOO LARGE	Faulty Home Sensor	Go to the Diagnostics-MOCON tab, search for PR or PS axis home switch inputs. Manually trigger the PR or PS sensors to verify the bits change states from 0 to 1. If the bits do not change states, use the electrical diagram below to determine which component has failed.
Alarm 391 Feature Disabled is generated commanding M180 & M181	The single switch auto window cannot be commanded independently.	Feature must be commanded by the pallet pool template. The customer needs to purchase an auto window install kit to get stand-alone functionality. Refer to AD documents that apply to your machine model. AD0652 - DT/DM/UMC-350 - Auto Window - Installation AD0663 - UMC Auto Window - Installation AD0669 - VMC Small - Auto Window - Installation
Pallet pool is displaying the wrong amount of pallets.	Parameter 740 Pallet Pool Max Pallet Count is set incorrectly	Change Parameter 740 to the correct pallet count
Alarm 9178 Load Station Inner Door Close Timeout and Built before June 2024	Pallet pool load station inner door didn't close within the required time limit.	Verify there is nothing obstructing the door close switch.
		Adjust the flag to the prox switch and make sure it toggles when in position.
		Check to see if the solenoid is functioning properly.
Alarm 9178 Load Station Inner Door Close Timeout and Built June 2024 or later	Pallet pool load station inner door didn't close within the required time limit.	Refer to the Auto Window Troubleshooting Guide for how to adjust and align the new clamp sensors properly.
Alarm 9889 Pallet Pool Slider Door Open Timeout and Built before June 2024	The slider door failed to open within the required time limit	Verify there is nothing obstructing the door open switch.
		Adjust the flag to the switch and make sure it toggles when in position.
		Check to see if the solenoid is functioning properly.
Alarm 9889 Pallet Pool Slider Door Open Timeout and Built June 2024 or later	The slider door failed to open within the required time limit	Refer to the Auto Window Troubleshooting Guide for how to adjust and align the new clamp sensors properly
Pallet "Missing" message appears on the pallet scheduler page whenever a pallet is loaded in the machine	The receiver clamp and unclamp switch are not adjusted correctly.	Go to I/O tab and verify that inputs 25 PALLET CHANGER PALLET UNCLMPED and 29 PALLET CHANGER PALLET CLAMPED toggle to the correct state. Adjust the clamp/unclamp switches until they are in the correct state.
Alarm 946 APC Pallet Clamp Timeout
Alarm 9116 APC Pallet is unclamp	The pallet clamp/unclamp inputs are in a invalid state.	Go to I/O tab and verify that inputs 25 PALLET CHANGER PALLET UNCLMPED and 29 PALLET CHANGER PALLET CLAMPED toggle to the correct state. Adjust the clamp/unclamp switches until they are in the correct state.
Alarm 15.165 PR-Axis Zero Return Margin is Too Small	The machine may have shifted during shipping	Redo the grid offsets and re-set the tool change offsets. For further instructions contact Haas Service for the internal procedure on how to do so.
Alarm 16.165 PS-Axis Zero Return Margin is Too Small	The machine may have shifted during shipping	Redo the grid offsets and re-set the tool change offsets. For further instructions contact Haas Service for the internal procedure on how to do so.
"No Pallet" message appears when selecting "Put away Load Station Pallet" and "Get highlighted Pallet"	Parameter 2129 was not set to "PP_Shelf_ A"	Use the USB Service key to go into Service Mode. Press [DIAGNOSTIC] Go to the PARAMETERS> Factory setting tab. Set the following factory settings value 2129[:] Pallet Loading Shelf = PP_Shelf_A.
There is air squeaking out when the receiver is at the top of its stroke.	The locating dowel pin is rubbing on the receiver clamp flag.	Add grease to the dowel pin to fix this noise.
VF-2YT 3 Station Pallet Pools Built before December 2022 Bolts are too short when replacing the pallet pool trolley plate.	Longer bolts are now used in the Pallet Pool assembly.	Order sixteen (16) of the longer bolts, PN: 40-0011.
The trolley plate is going over the locking pins at one or more pallet shelves and not hooking the pallets correctly.	The storage station shelf with this problem will need to be adjusted by its outer leveling foot.	Refer to step 2 in the Align Remaining Pallet Shelves section of the Pallet Pool Installation procedure. VF-2YT 3 Station Install VF-2YT 6 Station Install
The locating dowel pin fell out of the receiver casting.	The receiver camp plate was removed and caused a crash or the casting around the locating pin cracked.	The receiver will need to be replaced, refer to the VF - Pallet Pool Receiver Replacement procedure for the kit and instructions on how to replace.
Chips are getting and staying on the bottom of pallets.	The machine does not have the window brush kit installed.	Install the window brush kit, refer to the VF-Pallet Pool - Window Brush Retrofit Kit - Installation procedure for the kit and install instructions. If your application causes more chips than normal utilize the M50P0 wash-program, refer to the M50 Pallet Change Sequence page for more information.
Parts being mis-machined at an angle.	Chips are getting stuck under the clamp plate.	If your application causes more chips than normal utilize the M50P0 wash-program, refer to the M50 Pallet Change Sequence page for more information.
Inconsistent pallet rotation to each station.	The pallet rotate gearbox is loose on its mount.	Align pinion gear on gear box to the spur gear. Make sure gear is fully engaged. Tighten down all screws and torque them to spec. Recheck alignment for station load and unload. Refer to VMC-Pallet Pool Installation to align the stations.
Excessive amount of back lash on the pallet rotate.	The pallet rotate gearbox is loose on its mount.
"Clunk" sound when pallet transitions from saddle to storage stations.	Misalignment of PR axis compared to the storage shelf.	Refer to the VMC-PP Fine Adjusting Drop Off and Pick Up section below for further instruction on how to adjust PR for saddle to station alignment.
Pallet moves forward or backward during hook and unhook.	The storage station is not level or is not at the same height as the saddle	Place a long level or straight edge on station rollers and saddle rollers. Adjust the leveling feet for that station until the long level or straight edge contacts with at least 2 rollers the saddle and 2 rollers on the storage station.
Pallet moves forward or backward during hook and unhook.	Misalignment of PS axis compared to location of locking mechanism and storage shelf.	Refer to the VMC-PP Fine Adjusting Drop Off and Pick Up section below for further instruction on how to adjust PR for saddle to station alignment.
The APC receiver is slow to unclamp and unclamp.	Linear bearings have had excessive wear due to chips getting stuck under clamp plate.	Remove clamping plate and remove linear bearings. Check linear bearing to see if there are any debris marks on the bearing. If so, replace the linear bearings.
The APC receiver is in the process of unclamping the pallet when pallet pool starts to pull out the pallet from the machine.	Receiver clamp flag unmarks the unclamp sensor too early.	Replace receiver clamp flag with the most updated receiver clamp flag, part number 20-9823C.
Both sides of APC receiver does not unclamp and unclamp evenly.	The spring for the APC receiver is broken on the linear bearings.	Open up APC receiver and check to see if the springs are broken. If a receiver spring needs to be replaced, then all springs should be replaced. 1x 93-6017 should be ordered for VF-2YT PP machines and 2x 93-6017 should be ordered for VF-4 PP machines.
Setting 382 Disable Pallet Pool only has the "none" option available when going to enable/disable pallet pool.	Parameter 2128 was set to "Not Installed".	Use the USB Service key to go into Service Mode. Press [DIAGNOSTIC] Go to the PARAMETERS> Factory setting tab. Set the following factory settings value 2128[:] Pallet Pool Type = Hook.

Load Door I/O Status

Machine State	PP Load Door Open Input #31
Both Doors at the Load Station are closed.	0
One or both of the Load Station Doors are opened.	1

VMC-PP Fine Adjusting Drop Off and Pick Up

1

This procedure is to fine adjust the VMC-PP pick up and drop off of the pallets onto each individual station. Repeat this procedure to align multiple stations.

If this machine was built before 05/2025, download the latest configuration file for your machine from HBC and update the machine's configuration file.

Note: If the individual shelf parameters were adjusted and a patch file was not created, the configuration update will set the changed values back to the factory settings.

Note: When performing this procedure, change the dimensioning setting to MM using Setting 9.

2

Adjusting saddle to station alignment:

Use the USB Service key to go into Service Mode.

Enter pallet recovery page and press the letter of the station that needs adjustment then [DELETE] to rotate the pallet pool to the selected station.

Press [-Z] or [+Z] to select the Pallet Rotate Axis or Pallet Slide Axis

Test the transition from the ram to the shelf by jogging the pallet onto the station using PS. If the transition needs adjustment, press [INSERT] to bring the pallet back on to the saddle and adjust the PR in the needed direction and test again till the pallet transition is smooth.

VMC Pallet Pool	Tool Change Offset Basing Location
VF-2 3+1 Station	Shelf F
VF-2 6+1 Station	Shelf F
VF-4 5+1 Station	Shelf E

3

When going to fine adjust the shelf location at which the tool change offset is based on, the individual shelf parameter should not be adjusted. The tool change offset for the the PR or PS should be adjusted. Refer to the table to determine which shelf that is based on the pallet pool model.

Once the pallet is adjusted where you want it at the tool change offset basing shelf, Press [DIAGNOSTIC] Go to the PARAMETERS> Factory setting tab.

Search 15.078 for the PR-Axis Tool Change Offset

Type in PR then press [F2] to set the new tool change offset for that axis.

You will need to [ZERO RETURN] both the PR and PS axis after changing the tool change offset starting with the PS.

Note: Once this is done, the other shelves may need readjustment. Go through this procedure again skipping step 3 for each one of the shelves if needed.

4

Adjusting saddle to station alignment continued:

Once the PR is adjusted, take note of the Pallet Rotate Axis position in the Pallet Pool Status box and exit the pallet recovery page.

Press [DIAGNOSTIC] and go to the PARAMETERS> Factory setting tab.

Press [EMERGENCY STOP] then type in ROTARY and press [F1].

Find the parameter that coincides with the station you are trying to adjust.

Important: The parameter number will be between 2140 and 2149, 2314 and 2321, or 2380 and 2387.

Once the parameter is found, highlight the desired parameter and press [F2]. Double check that the populated value matches the noted value from the recovery page.

Go back to the recovery page and move the pallet pool into a state where you will be able to zero return the PS and PR axes.

[ZERO RETURN] the PS and PR axis starting with PS.

Once that has been done, test the pick up and drop off of the station.

5

Adjusting hook and unhook position:

Use the USB Service key to go into Service Mode.

Enter pallet recovery page and press the letter of the station that needs adjustment then [DELETE] to rotate the pallet pool to the selected station.

Press [-Z] or [+Z] to select the Pallet Rotate Axis or Pallet Slide Axis

Jog the pallet onto the desired station using the PS.

Important: Do NOT travel too far with the PS on to the station. You could run into the bump stop with the pallet and cause an overload alarm or cause damage to the shelf.

Once on the station, use the PR to rotate the trolley plate out of the hook of the pallet. Rotate the PS 4 degrees in the negative direction to do so. Check to see if the latch is in the slot on the pallet hook. If the latch is not in the correct spot, move the pallet until it is in the correct location on the station for the latch to engage.

Slowly rotate in the the trolley plate using PR while adjusting the PS to allow for a smooth transition between the trolley plate peg and the pallet hook [1]. Make sure the peg does not pull or push the pallet during the hook motion.

VMC Pallet Pool	Tool Change Offset Basing Location
VF-2 3+1 Station	Shelf F
VF-2 6+1 Station	Shelf F
VF-4 5+1 Station	Shelf E

6

When going to fine adjust the shelf location at which the tool change offset is based on, the individual shelf parameter should not be adjusted. The tool change offset for the the PR or PS should be adjusted. Refer to the table to determine which shelf that is based on the pallet pool model.

Once the pallet is adjusted where you want it at the tool change offset basing shelf, Press [DIAGNOSTIC] Go to the PARAMETERS> Factory setting tab.

Search 16.078 for the PS-Axis Tool Change Offset

Type in PS then press [F2] to set the new tool change offset for that axis.

You will need to [ZERO RETURN] both the PR and PS axis after changing the tool change offset starting with the PS.

Note: Once this is done, the other shelves may need readjustment. Go through this procedure again skipping step 6 for each one of the shelves if needed.

7

Adjusting hook and unhook position continued:

Once the PS is adjusted, take note of the Pallet Slide Axis position in the Pallet Pool Status box and exit the pallet recovery page.

Press [DIAGNOSTIC] and go to the PARAMETERS> Factory setting tab.

Press [EMERGENCY STOP] then type in SLIDE and press [F1].

Find the parameter that coincides with the station you are trying to adjust.

Note:The parameter number for Slide Offset will be between 2130 and 2139, 2306 and 2313, or 2372 and 2379.

Once the parameter is found, highlight the desired parameter and press [F2]. Double check that the populated value matches the noted value from the recovery page.

Go back to the recovery page and move the pallet pool into a state where you will be able to zero return the PS and PR axes.

Zero Return the PS and PR axis starting with PS.

Once that has been done, test the pick up and drop off of the shelf.