Daktronics Hoist Installation Manual - Manual (Page 14)

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Figure 30 illustrates the loft block as seen
from the Vortek hoist.
Using the example in Figure 29, the first loft
block closest to the center (#3) will feed onto
the load bearing sheave. The remaining wire
ropes 4 and 5 will pass through the block.
Be careful not to have the through cables
cross over each other when routing them.
The pass-through idler area on the block
is not load bearing. Make sure that the lift
line drops onto the load sheave for each
drop.
The last loft block will be a single line sheave
and will not contain a pass-through area.
Terminating the Wire Rope Cables
The cables have been fed through the loft
blocks assuring that there are no crossed lines
and the excess is on the ground.
In most situations the theater consultant or
architect will specify a trim height for the
battens to reside when at their lowest point. Be
sure to compensate for all attachment hardware
prior to cutting the cables to their fi nal length.
Do not cut the wire rope of double purchase
units. These must be terminated at the
I-beams on the dead-off connection.
Vortek hoists use 3/16" wire rope for all
standard installations. A 3/16" Nicopress
copper sleeve with thimble is used to terminate
the cable end to the turn buckle or trim chain.
Daktronics recommends that only copper
sleeves or zinc coated copper sleeves
be used for termination. Aluminum
sleeves are NOT acceptable for cable
terminations.
Be aware of minimum height requirements for
each batten. Double piped electrical battens
will need to have their cable terminations done
higher than normal single pipe battens.
Confirm the number of crimps required for
the copper sleeve by reviewing the Nicopress
crimp tool manual.
Figure 30: Load bearing sheave