Stagehand Pro 4: Recovering From Faults

Emergency Stop Fault

Inside the Stagehand Pro 4, a safety relay cuts power to the motor when the Emergency Stop signal is lost from the Showstopper Emergency Stop Input.

To recover from an Emergency Stop fault, check any of the following:

• The Showstopper Base shows a green Ready light.

• If any Showstopper emergency stop buttons are activated, release them.

• Confirm that a Showstopper emergency stop cable is connected between a Showstopper Base/Hub and the Stagehand Emergency Stop Input.

• Swap the Showstopper emergency stop cable in case of a faulty cable.

• With a multimeter, check for 24VDC on pins 1 & 5 of the Showstopper emergency stop cable. If everything above checks out and you don't see 24VDC, there's a wiring problem somewhere between the Showstopper and the safety relay in the Stagehand. Contact support.

Limit Faults

The Stagehand registers a limit fault when a corresponding control signal is lost from the Sensor Input. First, verify a cable is attached between the machine and the Sensor Input.

If the cable is plugged in, here's the next recovery options:

Reverse Limit

• Drive the machine forward using the manual controls until the fault is cleared.

• Temporarily press the REV limit override button to continue moving in the reverse direction.

Pressing the limit override button defeats the safety of the limit switches. Only qualified personnel should use the limit override buttons, and only use them with caution.

Driving off of a limit switch by running a cue is not recommended. It may sometimes work, but if there is even a single encoder count detected in the reverse direction, the cue will abort.

Forward Limit

• Drive the machine reverse using the manual controls until the fault is cleared.
• Temporarily press the FWD limit override button to continue moving in the reverse direction.

Pressing the limit override button defeats the safety of the limit switches. Only qualified personnel should use the limit override buttons, and only use them with caution.

Ultimate Limit

Unlike the forward and reverse initial limits, the loss of the Ultimate Limit signal disables motion in either direction. This behavior is intentional. Under normal operation, an Ultimate Limit signal faults only when an initial limit (forward or reverse) has failed to stop the machine.

Go to the machine. Investigate the cause of the Ultimate Limit Fault. Repair the problem with the initial limits.

You cannot jog off of an Ultimate Limit switch to clear the fault. Your options are:

• Mechanically adjust the position of the Ultimate Limit switch to clear the fault, if it has been set improperly.

• Temporarily press the ULT limit override button to move in a safe direction.

Pressing the limit override button defeats the safety of the limit switches. Only qualified personnel should use the limit override buttons, and only use them with caution.

Further steps

A broken, or disconnected, wire to a limit switch will also trigger the fault. If a limit switch fault fails to clear even after you have performed the steps above, check the following:

• Swap the cable on the Sensor Input. A bad cable will prevent the limit signal reaching the Stagehand.
• Inspect the mechanical connection of the limit switch to the machine to verify proper operation.

• Inspect the internal wiring of the limit switch to verify the limit wires are connected to terminals on the limit switch.

Drive Faults

The Stagehand Motion Controller registers a Drive Fault if it does not sense an "ready" signal from the VFD. Most often, this is caused by an internal fault in the VFD (such as a machine drawing too much current). The most common VFD faults and the remedies can be found here, or in the VFD manual.

3MB

A800 Faults.pdf

pdf

VFD Fault List

Here are some times that you see a Drive Fault that are not really a VFD fault:

• The emergency stop is engaged. This kills power to the VFD which prevents it from sending a "ready" signal.

• An internal wiring problem. Contact support.

Resetting a Drive Fault

After digesting the cause of the fault, you can clear the fault any of the following ways:

• Reset the VFD through Spikemark.
• Cycle the emergency stop. This cycles power to the VFD which will reset the fault.

• Press the red reset button on the VFD keypad.

VFD Fault History

Press the MODE button until the VFD keypad displays “E - - -” and you can view the Faults history of the drive. Spin the wheel on the keypad to scroll through the most recent 8 faults.

Brake Fault

The VFD monitors both brake contactors that power the load brake and motor brake. If the output state of the contactors doesn't match the commanded state, the internal "brakes OK" signal from the VFD to the motion controller is dropped.

For example, if the VFD tries to remove power from the brakes, but the contactor output is still allowing power to pass through, the contactor has welded shut. The VFD can sense this issue and disallow any further motion until the contactor is repaired or replaced.

Here are some times that you see a Brake Fault that are not really a Brake fault:

• The emergency stop is engaged. This kills power to the VFD which prevents it from sending a "ready" signal.

• An internal wiring problem. Contact support.

Sadly, if you truly have a Brake Fault, it means that one of the contactors is broken and needs to be sent back to Creative Conners for repair. This has yet to happen as of August 10, 2022 at 6:27pm EST since the Stagehand Pro launched in 2015, but someday I bet it will. We're ready — Contact Support.

Cross-Groove Fault

When the Cross-Groove signal is lost from the Sensor Input, the Stagehand registers a fault and stops all motion. The intention is to stop a winch or hoist, once the wire rope has jumped a groove on the drum, before a dangerous hazard arises.

To recover:

1. Go to the machine and inspect the wire rope for damage.

2. Press and hold the Sensor Override button.
3. Jog the machine in the proper direction to clear the jumped wire rope.
4. Release the Sensor Override button.

If the cross-groove sensor is not activated, check the wiring of the sensor. A disconnected wire to the cross-groove sensor will also trigger the fault.

Cross-groove faults often indicate improper rigging of the winch or hoist. The first mule, or diverter pulley, is either poorly aligned or too close to the drum. Move the pulley further from the hoist to reduce fleet angle and improve the alignment.

Load Cell Faults

Through Spikemark, you can set an Overweight Threshold and an Underweight Threshold. The Stagehand will halt motion if the sensed weight from the load cell drops below the Underweight Threshold, or rises above the Overweight Threshold.

To recover:

1. Determine the cause of the fault.

2. Press and hold the Sensor Override button.
3. Jog the machine in the proper direction to mitigate the hazard.
4. Release the Sensor Override button.

You can turn off load cell faults through Spikemark if you are not using the Load Cell input and experiencing spurious faults. Load cell faults will remain disabled until you reactive them in Spikemark.

The Overweight Threshold prevents the hoist or lift from picking up a load that is too heavy. The Underweight Threshold senses when the load is caught on an external obstruction and is no longer suspended on the hoist.

Interlock Faults

The Stagehand will prevent movement in one or both directions when a corresponding signal is lost from the Interlock Input.

To recover either:

• Clear the source of the fault

• Temporarily install the Interlock Terminator

Installing the Interlock Terminator will bypass all interlock sensors and should be done only by qualified personnel using sensible caution.