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(c) Compound 6:1 with a ratchet (Simple 2:1 pulling on a Simple 3:1)

(d) Compound 9:1 (Simple 3:1 pulling on a Simple 3:1)
Figure 177- Compound Pulley Systems Examples

COMPLEX PULLEY SYSTEM
Complex pulley systems do not meet the definition of either a simple or compound

system; rather they involve more variables in rigging. Complex pulley systems can have
pulleys moving toward the load and the anchor at the same time (Figure 178). With
some rare exceptions, complex pulley systems are employed less frequently within
rescue. Fortunately the same objective can be achieved with simple or compound
systems which are easier for rescuers to understand and rig.

Figure 178- Complex 3:1 (Spanish Burton)

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