3M DBI SALA Rollgliss User Instruction Manual page 4

2.4 GUIDE CABLE: Applications with a sloped descent require a Guide Cable (see Figure 2, item D). Systems requiring a
Guide Cable must be designed by a qualified person. Descent speed is affected by the angle at which the Guide Cable is
secured and the amount of sag in the Guide Cable. The Guide Cable must be installed with sufficient slope and limited sag
to ensure the user will reach the landing area in the event of an emergency descent. The Guide Cable and the anchorage
point must support the weight of the user in a descent. The Guide Cable must be 3/8 inch (.9525 cm) to 5/8 inch (1.5875
cm) wire rope. The operation of the Emergency Descent System should be verified by performing a test descent in
accordance with section 3.2.C.
ANCHORAGE STRENGTH - GUIDE CABLE: The table in Figure 2 provides approximate recommended anchorage
strengths for various system configurations using 115 ft. (35 m) long, 5/8 inch (1.5875 m), 7x19 steel aircraft cable.
Figure 2 - Installation Options & Guide Cable Anchorage Strengths
A Vertical Descent
B Sloped Angle Descent
C Guide Cable Suspension Bar
D1 Guide Cable - Theoretical Straight Line
D2
Guide Cable - Line with Sag
E Guide Cable Sleeve
F Angle of Guide Cable from Vertical
G
Initial Guide Cable Sag
H Center of Span
Angle of guide cable
from vertical
15 Degrees
15 Degrees
30 Degrees
30 Degrees
45 Degrees
45 Degrees
A
Length of system Initial guide cable sag
115 ft (35m) 11.1 ft (3.4 m)
200 ft (61m) 19.4 ft (5.9 m)
115 ft (35m) 9.8 ft (3.0 m)
200 ft (61m) 17.4 ft (5.3 m)
115 ft (35m) 8.3 ft (2.5 m)
200 ft (61m) 14.4 ft (4.4 m)
D1
D2
F
C
B
G
Recommended anchorage strength
(including 2:1 safety factor)
2200 lbs (9.79 kN)
2450 lbs (10.90 kN)
2400 lbs (10.68 kN)
2650 lbs (11.79 kN)
2800 lbs (12.46 kN)
3050 lbs (13.57 kN)
4
H
E