Y-4 Electric Switch Adjustment

1. 4th/top boom full retraction detection limit switch

Adjust the switch position so that its contact is shifted (opened/closed) when the top boom section is extended/retracted beyond the position where it is 5-8 mm (0.2-0.31 in) longer than its fully retracted length.

2. 2nd/3rd boom section full retraction detection switch

1. Adjust so that the switch turns OFF at the position when the No. 1 telescoping cylinder is extended 3 mm (0.12in).

2. After adjusting, apply screw locking agent to the nut and tighten it.

3. Jib lock pin detection proximity switch

Adjust the switch position so that the dimension A becomes 4-5 mm (0.16-0.2 in) with the jib stowed.

(*1): Apply the screw locking agent (Three-Bond 1401 or the equivalent).

4. Over-front detection proximity switch

Fully retract the boom and swing it to the over-front. Then, adjust the switch position so that the dimension A becomes 2.5-3 mm (0.1-0.12 in) and the dimension B becomes 1.5-2.5mm (0.06-0.1in).

(*1): Apply the screw locking agent (Three-Bond 1401 or the equivalent).