UMC/EC Pallet Pool - Troubleshooting Guide

Introduction

There are differences between the UMC/EC Pallet Pool and the VMC Pallet Pool, please refer to this troubleshooting guide for issues regarding the UMC/EC Pallet Pool (6/8/10/16/20 Station Pallet Pool options).

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

UMC-500/SS
UMC-750/SS
UMC-1000/SS
UMC-1250/SS
EC-400
VC-400

The Next Generation software on the machine must be version 100.20.000.1110or higher.

The 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.

Please refer to the UMC Installation Section or the HMC Installation Section in the Pallet Pool Service Manual for further information on how to install your respective machine.

Pallet Pool

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

SENSORS

PP Lifter Up
PP Lifter Down
PR Axis Home Switch

4. PP Load Door Open

5. PP Station Lock

6. UMC Pallet Slide Home Switch

Note: EC-400 Pallet Slide Home Switch is found underneath the ballscrew.

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.
Hydraulic oil leaks or sprays from the pallet locating pins during a pallet change.		Contact Haas Service.
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. DC/DT/DM/CM/MM/SMM/UMC-350 - Auto Window - Installation - AD0652 UMC Auto Window - Installation - AD0663 VMC - Auto Window - Installation - AD0669
Alarm 974 Pallet Pool Switch Fault	Chips accumulated at sensors.	Check the Pallet Lifter Down / Up sensors for chips and clean out any that are found. Recover Pallet Pool and try again. Use the illustrations to locate the sensors.
Alarm 974 Pallet Pool Switch Fault	The pallet pool state proximity sensors are not triggering.	Check the Pallet Lifter Down / Up sensor states and make sure the sensors are toggling when triggered. Use the Lifter UP/ Lifter Down I/O Status table below to determine the correct states of the sensor.
Alarm 975 Pallet Pool Lifter Down Time Out	Chips accumulated at sensors.	Check the Pallet Lifter Down / Up sensors for chips and clean out any that are found. Recover Pallet Pool and try again. Use the illustrations to locate the sensors.
Alarm 975 Pallet Pool Lifter Down Time Out	The pallet pool state proximity sensors are not triggering.	Check the Pallet Lifter Down / Up sensor states and make sure the sensors are toggling when triggered. Use the Lifter UP/ Lifter Down I/O Status table below to determine the correct states of the sensor. Verify the Pallet Pool Status Cable (P/N 33-0427) is pinned correctly. Use the Electrical Diagrams below.
Alarm 977 Pallet Pool Lifter Up Time Out	Insufficient hydraulic pressure or fluid volume.	Make sure the pump is turning on and building enough pressure to lift the Pallet Lifter.
	Pallet Lifter was not unclamped.	Check for any mechanical obstructions that are preventing the pallet lifter from rising.
	Damage to the Pallet Pool up switch or wiring.	Check the pallet lifter up and pallet lifter down sensors for proper operation. Use the Lifter UP/ Lifter Down I/O Status table below to determine the correct states of the sensor.
Alarm 9887 Pallet Pool Lifter is Up	The Lifter is up when attempting to retrieve a pallet.	Enter RECOVERY to attempt auto-recovery, or enter the recovery page to verify that the lifter is operational by commanding it up and down. Check PP Lifter Up (INPUT 38) and verify it is operating correctly. Use the Lifter UP/ Lifter Down I/O Status table below to determine the correct states of the sensor.
Alarm 9888 Pallet Pool Lifter is Down	The lifter is down while either retrieving a pallet or placing a pallet.	Enter RECOVERY to attempt auto-recovery. If auto-recovery fails, enter the recovery page to verify that the lifter is operational by commanding it up and down. Check PP Lifter Down (INPUT 41) and verify it is operating correctly. Use the Lifter UP/ Lifter Down I/O Status table below to determine the correct states of the sensor.
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
Pallet pool up & down solenoid are functioning inversely	Up & down solenoid cables are incorrectly labeled	Order 93-3268 or 93-3268, lower and lift solenoid cable kit for correctly labeled cables.
Pallet Changer Clamp/Unclamp mechanism operates in reverse.	The hydraulic lines are reversed.	Check at both ends of the hydraulic lift cylinder and hydraulic power unit and verify that they are set correctly.
Pallet Changer Clamp/Unclamp mechanism operates in reverse.	The pallet clamp/unclamp sensors are reversed.	With a Pallet on the receiver. Command the pallet to clamp and unclamp. 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. Check the terminal block, check that they are connected correctly.
Alarm 9889 Pallet Pool Slider Door Open Timeout	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.
		Verify there is nothing obstructing the door open switch.
Alarm 9890 Pallet Pool Slider Door Close Timeout	The slider door failed to close within the required time limit	Verify there is nothing obstructing the door open switch.
		Adjust the switch to the flag and make sure it toggles when in position
		Check to see if the solenoid is functioning properly.
Alarm 9892 Pallet Pool Slider Door Not Open	The slider door was detected to be closed when it is expected to be open	Check the area around the slider door for obstructions
Alarm 9892 Pallet Pool Slider Door Not Open		Verify the correct switch is in the correct location
Alarm 9893 Pallet Pool Slider Door Open	The slider door was detected to be open when it is expected to be closed	Check the area around the slider door for obstructions
Alarm 9893 Pallet Pool Slider Door Open		Verify the correct switch is in the correct location
Pallet "Missing" message appears on the pallet scheduler page whenever a pallet is loaded in the machine	The clamp and unclamp switch are not adjusted correctly	Go to I/O tab and verify that inputs 25 PALLET CHANGER PALLET UNCLMPED, 29 PALLET CHANGER PALLET CLAMPED, and Output 44 PALLET CHANGER UNCLAMPED toggle to the correct state. Adjust the clamp/unclamp switches until they are in the correct state.
Alarm 946 APC Pallet Clamp Timeout	The clamp and unclamp switch are not adjusted correctly
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.
Machine is sounding clunky during the majority of the load and pick up cycles	The machine may have shifted during shipping	The tool change offsets will need to be adjusted. 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.
For UMC-1250 Machines built before 8/2023: Pallet's are not sitting flush on the pallet storage stations	Diameter of the slip fit holes on the pallet is not correct.	Refer to the UMC-1250 Pallet Slip Fit Hole Diameter section for further instructions.
Pallets not transitioning smoothly to/from forks to/from storage shelf during pick up and drop off	Mechanical misalignment of shelf location	Refer to UMC/EC-PP Fine Adjustment Drop Off and Pick Up section below to fine tune the pallet pool drop off and pick up on your machine.
	The machine may have shifted during shipping

Lifter Up/Lifter Down I/O Status

Machine State

PP Lifter Up

Input #38

PP Lifter Down

Input #41

PP Pallet Lift

Output #166

PP Pallet Lower

Output #167

Pallet Pool Lifter is Up

1

0

1

0

Pallet Pool Lifter is Down

0

1

0

1

Load Door I/O Status

Machine State	PP Load Door Open Input #31	PP Station Lock Input #33
Door is closed and the station lock is at the home position	0	1
Door is open and the station lock is at the home position	1	1
Door is closed and the station lock is not at the home position	0	0

UMC-1250 Slip Fit Hole Diameter

Rework the holes labeled [B] and [C] to the size specified in the image.

UMC/EC-PP Fine Adjusting Drop Off and Pick Up

1

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

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

Use these axes to jog the ram into position to allow for smooth drop off and pick up from the station.

Test the position by pressing [ALTER] to raise and lower the ram.

Take note of the Pallet Rotate Axis position and the Pallet Slide Axis position in the Pallet Pool Status box.

3

Once a desired position is found, exit recovery by pressing [RECOVERY].

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

Press [EMERGENCY STOP].

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, type in the noted value for the PS axis and set the new slide offset for the desired station letter using that value.

4

Type in ROTARY and press [F1].

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

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

Once the parameter is found, type in the noted value from the PR axis and set the new rotary offset for the desired station letter using that value.

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.

Electrical Diagrams

Pallet Pool Input Status and Solenoid Output

PR/PS Switch and Servo Motor Connection to MainCon PCB