b)Procedure. Remove load from the hook. To disconnect the geared limit switch refer to Figure 7-2. Remove the limit switch cover then loosen the two (2) screws holding the locking plate in place. Allow the locking plate to slide down and disengage from the adjustment discs. Do not rotate the adjustment discs.

CAUTION

Damage to the hoist may occur if the block operated limit switch fails during testing.

Damage can be avoided by immediately releasing the pushbutton once the lower block has traveled through the limit switch weight.

The block operated limit switch may now be tested by slowly and carefully raising the hook until the limit switch weight contacts the lower block. If the hook does not stop when the limit switch weight is lifted, immediately release the pushbutton before damage to your hoist occurs. If the block operated switch functions properly, proceed by testing in the same manner with rated load on the hook.

Once it has been determined that the block operated limit switch is functioning properly, the geared limit switch must be reconnected and tested.

Position the lower block three inches (3”) below the point where the block operated limit switch is activated. The geared limit switch shall be reconnected by sliding the locking plate back into position ensuring slots on adjustment discs are fully engaged and tightening locking plate screws to 4 in- lbs. (See Figure 7-2). The geared limit switch must then be tested.

Test the geared limit switch by raising the lower block until it stops. Ensure that the geared limit switch stopped the hoist before the block operated limit switch was activated. If this is not the case see Section VII, Paragraph 7-3 for adjusting the geared limit switch. Replace geared limit switch cover when testing and adjusting is complete.

WARNING

Check limit switch operation carefully, without load, before placing hoist in service. If misadjusted, SEVERE DAMAGE AND/OR A DROPPED LOAD COULD RESULT. Allow 3” for hook drift in both directions. Never allow less than two (2) complete wraps of rope on drum with hook in lowest position.

5-13. TESTING HOIST.

a)General. Testing shall be performed in accordance with ANSI B30.16-2 and this manual. Before placing hoist in service, hoist should be tested to insure safe operation when hoist has been disassembled and reassembled. To test, suspend hoist from an overhead supporting member of sufficient strength to support the weight of the hoist and the rated load. Connect hoist to power supply as shown on hoist nameplate and perform the checks listed in b) and c) below.

b)Check hoist as outlined in PRE-

OPERATION CHECKS, SECTION II, Paragraph 2-4.

c)Check hoist with rated load.

(1)Attach rated load to lower hook.

(2)Depress “UP” push button and raise load. When push button is released, hoist should stop immediately and hold load at that level.

(3)Depress “DOWN” push button, lower load a short distance and release button. Hoist should stop immediately and hold load at that level.

NOTE:

If load drifts downward slowly in step 2 or 3 above, motor brake requires adjustment – see Motor Brake Adjustment – SECTION VII, Paragraph 7-1.

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Yale 11353395D manual Testing Hoist