When testing the operation of a hoist, it is important to test the upper and lower limits. FDA conveyor limits prevent damage to the hoist, prevent the hook seat from entering the hoist, and prevent the chain from coming out of the hoist. You should perform this test as part of your pre-operation inspection. If you are testing a dual-speed hoist, you should test the limit switches at both speeds.

Before testing, there are some safety precautions you should follow

1.Make sure the area under the hoist or crane is clear of obstructions. Also, check if there is anyone under the hoist or in the path, including yourself.

2.Make sure there is no load on the hoist.

3.Be prepared to stop the hoist operation by pressing the emergency stop button.

After that, follow the steps below to measure the upper and lower limits:

1.With no load on the hoist, control the hoist hook to run upward.

2.Whether there is any abnormal sound when the hoist is running.

3.The limit switch should stop the hoist before the hook seat hits the hoist. If it fails to run, or you think it will fail, don't hit the bottom of the hoist. This may damage the hoist.

4.If the limit switch fails, do not use the hoist.

5.Next, test the operation of the lower limit switch by controlling the hoist hook to move downward.

6.Follow the same steps as when testing the upper limit switch. Listen for any unusual sounds as the hook descends.

7.Check the chain or wire rope for defects.

8.Also if the limit switch fails, take the hoist out of service.

Testing the upper and lower limits of your hoist is an important part of your hoist pre-operation inspection. If at any time you have questions about the function of the limit switches on your hoist or think there is a problem, take the hoist out of service and contact the manufacturer.