Harrington Hoists RHN02D-20A-20D Series, Руководство пользователя

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
Turning to the right: switching point is moved “upwards”.
4) Adjusting the gear limit switch

All the cam discs can be moved together with the aid of the black setscrew (SO), Figure 3-21 .
The settings of the individual contacts relative to one another remain unchanged. The gear
ratio inside the limit switch is very high and in some instances it might require many revolutions
of the set screws to adjust the proper position.

Set the limit switch using a screwdriver and without using excessive force. Do not use
a power screwdriver or similar tool.

Set the switching points in the following sequence:
1. BLS
↑
( Set at Factory, only adjust if completely necessary ).
2. S1
↑
( Set at factory, only adjust if installing a new limit switch )
3. S3
↑
4. S4
↑↑
5. S2
↓

The safety limit (S1
↑
), the block operated upper limit (BLS
↑
), the upper limit (S3
↑
), and the
high to slow speed transition limit (S4
↑↑
) are all adjusted at the factory according to the
procedure below. The only limit that needs to be adjusted at “start-up” in the field is the
lower limit S2
↓
. The lower limit S2
↓
should be set so the bottom block stops approximately
3” above the ground (load platform).
5) Block Operated Upper Limit, BLS
↑

Lift bottom hook block to a distance of >2 ¾ ” (55mm) from the top of the hook block to the
bottom of the clearance object.

If necessary, turn setscrew (S2) to the right beforehand.

Set BLS rope length so that switch is activated in this position
6) Safety Limit, S1
↑

Raise bottom hook block until BLS is activated

Turn setscrew (S1) to the left until contact S1
↑
switches audibly

Turn set screw (S1) back to the right approx. ½ turn.
7) Upper Limit, S3
↑

Raise bottom hook block until BLS is activated

Turn set screw S3 to the left until contact S3 switches audibly

Turn setscrew S3 approx. ½ turn to the left

Lower and raise bottom hook block until S3
↑
is activated
8) High to Low Speed Transition Limit, S4
↑↑

After the upper limit S3
↑
has been activated, lower bottom hook block by at least 2.0in
(50mm)

Turn setscrew S4 to the left until contact S4 switches audibly

Check disconnect by operating hoist in the ”up” direction point in high speed.
9) Lower Limit, S2
↓

Minimum clearance between rope guide (S) and rope anchorage clamps (K) should be equal
to or greater than 3/4” (20mm)

Set bottom hook position so that the bottom block does not touch the ground, approximately 3
inches above ground or platform level.(do not allow the formation of slack rope).

Make sure there are at least 3 wraps of wire rope left on the drum when adjusting for the
lowest hook position