When it comes to commonly replaced crane parts, the overhead crane pendant is one of the most frequently broken and replaced. That’s because the pendant, the control unit for the crane, undergoes more handling than any other component.
In my many years of crane repair experience, I’ve found a high percentage of crane breakdowns involve the controls. When I get a call to repair a broken down industrial crane, the pendant station is typically the first place I check.
Limiting future breakdowns is often a matter of choosing the best overhead crane pendant for your industrial crane. In choosing a replacement pendant station, you need to know:
- How many functions do you need to control? One for the up-down action of the hoist? Two for a monorail crane to control the hoist and trolley? Or three for the hoist, trolley and bridge functions?
- How many speeds do you need? A single speed, five speed or something in between?
- What kind of start-stop circuit do you need? With a maintain start-stop, pressing the start button locks the control circuit into place until the stop button is pressed. By contrast, a momentary start-stop controls a seal in circuit on the mainline contactor, holding the circuit in closed position until the stop button is depressed. In practical terms, it enables the crane operator to pause crane movement.
- Is your crane equipped with E-stop? If so, you’ll want a pendant with an emergency stop button.
When selecting an overhead crane pendant station, you also should consider the environment where the crane operates. For example, will the pendant need to keep out moisture and dust, or be able to withstand impacts?
Strain relief is another important consideration for your pendant. A strain relief cable runs along the conductor, but is a little shorter than the conductor so that the cable takes the strain and protects the conductor when the pendant is pulled. Some pendant stations feature internal strain relief, in which the relief cable runs inside the pendant cable and is covered by the outer insulation. By contrast, the more common external strain relief utilizes a cable that runs outside the pendant cord.
Today, many new industrial cranes come with remote or radio controls as standard equipment. Remote controls are often preferred for applications where it’s best to keep operators away from the equipment. They also are a good alternative for cranes with a significantly long pendant drop—the distance from the pendant station to the pendant cable’s crane connection. The longer the drop, the greater the risk of the cable getting tangled in equipment or other obstructions.
To make sure you have the right overhead crane pendant or radio control for your industrial cranes, contact a Konecranes sales representative.