3.1.4.3.4.3 Incorrect attachment (Previously 3.1.4.3.7 in ANSI 1992)
May 2, 2011 to Present:
Thedesignershallincorporateprovisionstostopthegrip andcarrierinacontrolled fashionwhenagripis incorrectlyattachedtotherope.
a) monocablesystems
Thepathoftheropefromtheterminal where passengersareloadedshallbeapproximatelylevel orinclinedupwardforalengthatleastequalto:
L(feet) = V2(ft/minute) or
14,400
L(meters) = V2 (meter/sec)
1.22
L=Lengthoflevelorinclinedupwardrope
V=ropespeedduringpassengerloadingatthat station
Anincorrectlyattachedgriptrippingthelastchecking switchshallcausetheropetostopina distancenot greaterthanthecalculatedlength“L”orinthecase whereagreater lengthoflevelorinclined upward ropeisprovided, inadistancenotgreaterthanthe lengthprovided.
b) bicablesystems
Onbicablesystemsterminals, thedesignershall incorporateprovisionstostopinacontrolledfashion anincorrectly attachedcarrierafterthegrip attachmentpoint.
Asign,visibletotheoperatingpersonnelinthestation requiring thereduced ropespeed,isrequired. Itshall statethe“maximumropespeedduringloading”(see tableD-1(s)) iftheaerialliftmustbeslowed belowthe designedspeedtocomplywith3.1.4.3.4.3(a).
May 15, 2000 to May 2, 2011:
The designer shall incorporate provisions to stop the grip and carrier in a controlled fashion when a grip is incorrectly attached to the rope. The path of the rope from the terminal where passengers are loaded shall be approximately level or inclined upward for a length at least equal to:
L (feet)=V2(ft/minute)or
14,400
L (meters)=V2(meter/sec)
1.22
L =Length of level or inclined upward rope
V =rope speed during passenger loading at that station
An incorrectly attached grip tripping the last checking switch shall cause the rope to stop in a distance not greater than the calculated length “L” or in the case where a greater length of level or inclined upward rope is provided, in a distance not greater than the length provided.
Nov. 1, 1991 to May 15, 2000
At each carrier launching position (any area where a grip is designed to attach to the haul rope), devices shall be installed that will stop the aerial lift if any grip incorrectly attaches to the haul rope.
When a grip is detected to be incorrectly attached to the rope, the designer shall incorporate provisions to stop the grip and carrier so that it will come to a stop in a controlled fashion, or the path of the rope from the terminal where passengers are loaded shall be approximately level or inclined upward for a length at least equal to the calculated stopping distance. The level or sloping length of rope shall be measured from the last switch where the grip is checked for attachment to the rope. Calculated stopping distance for this subsection is equal to:
D = V2(ft/minute)orD =V2(meter/sec)
14,4001.22
D =stopping distance
V =rope speed during passenger loading at that station
Upon clamping to the haul rope or haul-carrying rope, the carrier velocity and rope speed shall not vary sufficiently to introduce unduly either passenger discomfort or mechanical wear.