How to troubleshoot, Upgrade and/or Retrofit your Accurpress Hydraulic Press Brake Controls

What do you do if your Accurpress Hydraulic Press Brake stops working?

These are helpful tips from the Accurpress Press Brake User Manual that can be used for troubleshooting your Accurpress Hydraulic Press Brake.

Refer to Section 3 of your manual for Safety procedures prior to any servicing.

All personnel servicing any part of the press brake must follow safe work practices.

  • Ensure that all other personnel are clear of the die area (point of operation) while the press brake is being serviced.
  • Follow in-plant machine lockout procedures to prevent press brake operation during service or troubleshooting.
  • Post equipment maintenance warning signs.
  • Utilize proper personal protective equipment as required by regulatory requirements.

Service personnel may require basic diagnostic tools, such as an electric multimeter for assessing electrical control problems and a pressure gauge for assessing hydraulic control problems.

Service personnel using manual overrides on the hydraulic directional valves should proceed with extreme caution to prevent personal injury or damage to the dies, limit switches or hydraulic cylinders, due to overtravel.

Section 10.1 of your manual identifies typical malfunctions, their possible causes, and suggested solutions.  Section 10.2 discusses instances of forming variance.

10.1 – How to troubleshoot Malfunctions in Accurpress Hydraulic Press Brakes

 

10.1.1 – What do I do when the Accurpress Hydraulic Press Brake Pump drive is not working or will not start?

Cause Solution
Shop electrical supply disconnect switch is OFF Turn disconnect switch ON.
Press Brake main disconnect switch is OFF Turn disconnect switch ON.
The emergency STOP push button is pushed in. Turn Emergency STOP pushbutton ¼ clockwise to release, then push SART push button.
Control circuit fuse FU1 is blown. Check for a possible cause. Remedy cause and replace the fuse.
Loose wire connections in control circuit wiring. Check for electrical control writing continuity using a multimeter and control schematic. Repair as required.

 

10.1.2 – What if the Hydraulic Press Brake Pump Drive Motor is running but the press ram will not cycle?

Cause Solution
Ram control is disabled. (RAM ACTIVE light is flashing.) Toggle RAM ENABLE key.
Backgauge control is disabled. Enable backgauge control.
Control setting is not the mode being used. (Hand or foot light is flashing.) Change the control mode to the desired setting.
Neither calibration, run, nor third party control mode is selected. Select calibration, run or third-party control mode.
Ram (Y-axis) is uncalibrated. Calibrate ram.
Backgauge (Y-axis) is uncalibrated. Calibrate backgauge.
Operational CNC systems interface is incompatible with existing electrical control. Contract CNC system dealer/manufacturer.
ETS system parameter configuration is incorrect. Consult factory service for procedures in re-setting system configuration.
Motor rotation is incorrect. Check the phase sequence at the main supply voltage connection to disconnect switch. Ensure sequence is: 1-2-3 (red-black-white).
Loose connection / broken wire in operator control pedestal cable or defective electrical contact blocks. Check for electrical continuity from operator control pedestal to the main electrical cabinet. Repair as appropriate.
Defective ram down the overrun limit switch or loose/broken electrical connection. Check for electrical continuity from the footswitch through to the DOWN solenoids. Repair as appropriate.
The hydraulic relief valve is stuck in an OPEN position. Try to cycle the press ram down using the hydraulic valve.

 

 

10.1.3 – Why will the Accurpress Hydraulic Press ram cycle down in slow speed only?

Cause Solution
Speed change position is not set correctly. Optimum setting for speed change is at punch contact of the part being formed.
High volume valve DOWN solenoid is defective. Check electrical continuity to and at the solenoid. Repair as appropriate.

 

10.1.4 – What do I do when the Ram Hesitates or stops at speed change point or part contact Point?

Cause Solution
Press ram is free falling faster than the system can deliver oil to the hydraulic cylinders. Check the press ram ways assembly. Refer to section 9.3, “Mechanical System Adjustments” in the press brake manual.
High pressure relief valve is not maintaining preset relief pressure setting. Remove the high-pressure relief cartridge assembly from the manifold block and inspect the O-rings for damage.

Check the center sliding spool to confirm valve functionality. Clean with solvent and compressed air to remove any foreign particles. Re-Install and test valve.

10.1.5 – Why doesn’t the Press ram return to the program up-limit?

Cause Solution
Control mode is set to JOG. Switch to AUTO or MAN mode, then activate footswitch or palm pushbuttons.
Loose connection/Broken wire in operator control pedestal cable or defective electrical contact block. Check for electrical continuity from the operator control pedestal through to the up solenoids. Repair as appropriate.
The ram up-limit switch is stuck or damaged in the activated position. Check the limit switch mechanical functionality and electrical continuity. Repair as appropriate.

10.1.6 – What do I do when the Press ram does not stop at a bend point.

Cause Solution
Hydraulic directional valve malfunction. Manually activate the overrides to check pilot valve mechanical functionality. Make sure there is no obstruction of the pilot spool or the valve spool centering springs.

 

10.1.7 – How do I prevent the Ram from stopping and/or reversing before developing full tonnage or completing the bend?

Cause Solution
Program bend point setting is incorrect. Check program bend point to see if the press ram reaches the recorded position.
Tonnage control is set too low to complete the bend. Check tonnage display and adjust for higher tonnage.
Excessive off-center load is causing torsion safety limit switch activation. Move part being formed closer to center on the press bed.
Slow speed change position setting is incorrect. Optimum setting for speed change is at punch contact of the part being formed.

 

10.1.8 – Why does the Press tonnage display show full tonnage, but the hydraulic press fails to complete the bend?

Cause Solution
Part’s material properties are incompatible with the press brake and die configuration. Check material properties to confirm that the bend can be executed with the existing set-up.
Increase die opening to reduce the press ram tonnage required to form the part.
Decrease part length being formed to reduce the press tonnage required.

 

10.1.9 – Why doesn’t the Backgauge advance to the next flange length step?

Cause Solution
Incorrect programming of the number of steps for the job. Confirm backgauge program steps reflect the job requirement.
Backgauge position dimension per step is not programmed. Verify or modify the backgauge step program dimension.
STOP pushbutton is detented OFF. Reset backgauge STOP pushbutton to ON (1/4 turn clockwise).

 

10.1.10 – What do I do when the Accurpress Hydraulic press brake system is overheating?

Cause Solution
The program up-limit setting is incorrectly adjusted and the ram up-limit switch is failing. This is allowing cylinders to fully retract, which relieves hydraulic flow over the system relief valve. Check ram up-limit switch adjustment and functionality to stop ram up travel, and ETS HIGH set position.
The operator is continuously attempting to form parts over the capacity of the press brake. Ensure the press brake speed change point is above the material to be formed and the tonnage indicator is registering within the rated tonnage.
Accurpress Hydraulic system high pressure relief valve is relieving prematurely. Remove the high-pressure relief cartridge assembly from the manifold block and examine O-rings for damage.
Push the center sliding spool to confirm valve functionality. Clean with solvent and compressed air to remove any foreign particles. Re-install then test valve.
The high-pressure pump cartridge is defective or worn. resulting in loss of flow and pressure. Test the pump flow delivery and pressure at a hydraulic service center. If such facilities are not convenient, the high-pressure cartridge “P2” can be removed and examined for mechanical damage and wear. Replace the cartridge or the complete pump, as required.
The coupling element between the electric motor and hydraulic pump is worn or disintegrated. Inspect and replace as required.

 

10.1.11 – Why is the Hydraulic pump too noisy?

Cause Solution
The hydraulic fluid level is low. Check fluid level when press ram is in the up position. If required, add fluid until visible in sight gauge.
Pump inlet suction strainer is plugged or obstructed. Check the fluid condition. Replace hydraulic strainer, fluid, and hydraulic filter as required.
Hydraulic inlet piping or connections are loose” causing the pump to ingest air. Check piping connections, O-ring at the pump to Inlet flange, and tighten inlet’ flange bolts.
Hydraulic pump shaft seal is defective, causing the pump to ingest air. Check shaft seal for wear or damage. Replace if required.

 

10.1.12 – Why are the operating modes not toggling to next setting?

Cause Solution
EDIT selector switch is set to LOCK. Verify written job operating procedure and modify operating mode for compliance.

 

10.1.13 – What do I do when the ETS or third-party CNC gauging is inoperative or malfunctioning?

Cause Solution
Incorrect CNC gauging interface. Verify interface documentation and installation. Contact factory service to confirm press brake interface requirements.

 

10.2 – Accurpress Hydraulic Press Brake Troubleshooting: Forming Variance

 

10.2.1 – What do you do when there is an unequal angle at each end of the formed part?

Cause Solution
Variance in metal thickness. Check material thickness at both ends of the part. Offset the ram parallel to compensate for material thickness variance.
Variance in tooling height build-up at each end. Offset the ram parallel to compensate for any tooling variance.

 

10.2.2 – How do I stop the inconsistency in the formed parts?

Cause Solution
Press ram, bed, and tooling are coated with rust-proofing. Remove die set, clean all parts with solvent, re-assemble and readjust.
Tooling does not lie flat on press bed cap. Check clearance with feeler gauges. Shim between press bed and tooling. Or mechanically straighten as required.
Tooling is worn. Re-machine forming surfaces of tooling.
Utilize localized shimming practices to compensate for worn areas.

 

10.2.3 – Why does each formed part exhibit a consistent angle from end to end, but there is inconsistency from part to part?

Cause Solution
Press ram is free falling. Check press ram ways assembly adjustment.
A high-pressure directional control valve is defective or worn. Disassemble and inspect for damage or worn spools landings, spools, springs, or for contaminants.

 

10.2.4 – Why does each formed part exhibit an inconsistent angle from end to end?

Cause Solution
Rocker arm clamping screws are loose. Locate and retorque.
Right ram lug clamping screws are loose. Locate and retorque.
Left ram lug clamping screws are loose. Locate and, if loose, consult factory service before retorquing.
Connecting rod clamping screws are loose. Locate and, if loose, consult factory service before retorquing.
Connecting rod lower spherical bearing is worn or damaged. Locate and, if loose, consult factory service before retorquing.

 

10.2.5 – Why is the Accurpress hydraulic press brake under bending in the middle of the formed part?

Cause Solution
Tooling is worn in the center due to continuous forming of small parts in one location. Remachine forming surfaces of tooling.
Utilize localized shimming practices to compensate for worn areas.
Press bed and ram are worn in the center due to continuous forming of small parts in one location. Remachine forming surfaces of press bed and ram.
Utilize localized shimming practices to compensate for worn areas.

 

10.3 – Troubleshooting ETS Messages for Accurpress Hydraulic Press Brakes

The software includes detailed messages to describe machine operation. One or more messages will be displayed to either explain an error or diagnose a problem.

10.3.1 – Accurpress Hydraulic Press Brake Error Messages

If the palm pushbutton or footswitch are activated and there is no motion for two seconds, the error message(s) will be displayed. In this case, the message(s) will explain the error. Each message has an associated number:
100 series – indicates problems are normally corrected by proper machine setup and operation.
900 series – indicates parts should be replaced, or the machine requires servicing.
The “Explanation/Solution” column gives the most common reason and/or possible solutions for the message, starting with the most probable.

 

Number Message Explanation/Solution
099 ACR held on by NNN The number NNN signifies why the Auto-Cycle-Relay remains on at the end of the cycle when the controls have been released.
1) Over 16 – two pedestal problem.
2) 12 thru 16 – both palm pushbuttons are sensed on
3) 8 thru 12 – right palm pushbutton is sensed on.
4) thru 8 – left palm pushbutton is sensed on.
5) Under 2 – footswitch is sensed on.
901 Fuse F2 Blown 1) Random failure – replace the fuse.
2) Chronic failure – normally indicates a failed solenoid valve.
102 Hydraulics Off 1) Check that the pedestal STOP button is released.
2) if ‘901’ also, replace the main PLC board fuse.
3) Check overloads on the main contactor.
4) Check of power at J4, G9, G10, J8.
5) Hydraulics safety cutout must be on
– check that there is no voltage at J6 when the start button is pushed.
-if 120V at J6, a problem with the main PLC board.
6) if the pump is running there is a PLC sensor fault, machine operation is not affected.
103 Ramup Activated 1) Ensure that RAM UP is not being pushed.
2) Check for power at G1
– if power present, suspect short in the snake, pedestal wiring, or RAM UP switch.
-if no power, there is a PLC main board problem.
104 Hand Required – Not foot 1) Check that control mode is correct.
2) pedestal problem:
– fault in top contact of the footswitch.
– break in the wiring to pedestal board P1-6.
– pedestal board fault (R14).

 

Number Message Explanation/Solution
105 Foot Required – Not Hand 1) Check that control mode is correct
2) Pedestal Problem:
– Fault in contact of palm pushbutton.
– break in the wiring to pedestal board P1-3 or P1-4.
– pedestal board fault (R7 or R8).
106 H/FtOn, NoAC Pwr 1) Footswitch not fully depressed.
2) Pedestal logic problem
– change control modes and the error message should change to 104 or 105, follow message instruction.
3) Check for obstruction under footswitch.
4) Check continuity from J4 to G3 with footswitch engaged.
5) Check continuity from J4 to G2 with palm pushbutton engaged.
6) Check that hand/foot relay (RE2) is 12VDC.
7) Main PLC board has failed (not user replaceable).
107 Down Limit Open Down limit microswitch is open.
108 Torque Limit Open Torque limit microswitch is open.
109 Light Curtain Open Light curtain has been activated.
110 3rd Party Dn Open 3rd party down limit is open.
111 Not Run-Calib Md Need to switch to run mode or calibration mode.
112 Ram uncalibrated Need to calibrate press ram (Y-axis).
113 Ram not enabled Enable press ram by pressing the RAM ENABLE button.

 

Number Message Explanation/Solution
114 Xaxis off target 1) Wait for backguage to reach programmed Position.
2) Enable the backguage by pressing the GUAGE ENABLE button.
3) Check for any obstruction of the backguage.
4) Re-calibrate the backguage X-axis.
115 Anti-tie-downErr 1) Operate palm pushbuttons simultaneously.
2) Check for switch or wiring error in pedestal.
116 DownLimit Reached Ram has reached its target position and can go no further. This is not a fault.
117 TonLimit Reched 1) Check that tonnage limit is set properly.
2) Check the setting of K factor or other parameters.
3) Tonnage sensor failure.
118 Retrip RDS/HFT In either Ram Double-Stop mode or Hand-Foot transfer mode, the hand/foot switch was not released within 2 seconds at the slow speed change point.
119 Retrip ErrBitSet Press ram will go up with next activation. Ram has stopped as a result of:
1) Switched out of JOG mode or changing modes.
2) Ram enabled when not at top of the stroke.
3) HI point reduced when hydraulics are on.
4) Any other unauthorized motion.
120 Retrip ACRBit Set Press Ram is prevented from going up at the end of the stroke. Ram will go up with next activation.

 

10.3.2 – Diagnostic Messages for Accurpress Hydraulic Press Brake Controls

Number Message Solution
121 Ton Sensor Problem 1) Adjust Zero on PLC board.
2) Check ton sensor input wires and connector.
3) Failed ton sensor.
122 Valid Bend Limit Usually Indicates the desired operation.
123 Valid Ton Limit Usually Indicates desired operation.
124 Error Ton Cutout Usually Indicates ton limit set too low.
125 Ramup Sw Cutout Occurs when Ram Up is activated before the bend limit has been reached. Usually, this is the operator’s intent.
126 Pedestal PwrLoss Occurs if the hand/foot is de-activated before the ram has reached the bend limit. Usually, this is the operator’s intent.
127 X axis target loss Retract must be programmed at least 0.300 from top of the stroke.

Accurpress Press Brake Parts Manual Slideshow

Press Brake Main Assembly
Accurpress Press Brake: Press Brake Main Assembly

How do I upgrade my Accurpress Hydraulic Press Brake Controls?

Check out Automec’s Accurpress Control Upgrade!

Automec can utilize existing Accurpress back gauges and replace the AP2 with our CNC 150 or CNC 300 Press Brake Backgauge Control.

Automec upgrades its competitors’ existing press brake/ back gauge controls for less than 1/2 the price of purchasing a completely new system. We offer 2-axis control upgrades for Hurco® and Accurpress ® backgauges, and we offer to retrofit press brake controls for many press brakes in the field today.

Call 781-893-3403 for more information.

Watch our step by step instructional video for replacing the Accurpress ® AP2 with an Automec Press Brake Backgauge Control