Banner SC22-3E Safety Controller with Ethernet - Manual (Page 102)

Ds = the separation (safety) distance in inches
S = the minimum safety distance in millimeters
K = OSHA/ANSI and ISO 13855 hand speed constant of 1600mm/s (63" per second) (NOTE 1 below)
T = the overall stop time of the machine, measured from the actuation of the sensing function to the final ceasing of all motion.
Ts = the stop time (in seconds) of the machine, measured from the application of the “stop” signal to the final ceasing of all motion,
including stop times of all relevant control elements, and measured at maximum machine velocity (see NOTE 2)
Tr = the response time of the Safety Controller as measured from the time a stop is signalled by either hand control. (Controller default
response is 0.010 seconds, plus any additional closed-to-open debounce time. If the debounce time is adjusted, the time in excess of 6
ms (=default closed-to-open debounce time) must be added to the stated response; refer to Specifications, Section 2.2.)
Th = the response time of the slowest hand control (from the time when a hand disengages that control until the switch opens; see NOTE
3)
Tm = the maximum time (in seconds) the machine takes to cease all motion after it has been tripped. For full-revolution clutch presses
with only one engaging point, Tm is equal to the time necessary for one and one-half revolutions of the crankshaft. For full-revolution
clutch presses with more than one engaging point, Tm is calculated as follows:
Tm = (1/2 + 1/N) x Tcy
where:
N = number of clutch engaging points per revolution
Tcy = time (in seconds) necessary to complete one revolution of the crankshaft
C = the added distance due to depth penetration factor: 250 mm, per ISO 13855. The ISO 13855 “C” factor can be reduced to 0 if the risk
of encroachment is eliminated, but the safety distance must always be 100 mm or greater.
NOTES:
1. The hand-speed constant (K) has been determined by various studies, and although these studies indicate speeds of 1600mm/s
(63”/second), 2000 mm/s (79”/second), to more than 2540 mm/s (100”/second), they are not conclusive determinations. The em-
ployer should consider all factors, including the physical ability of the operator, when determining the value of K to be used.
2. Ts is usually measured by a stop-time measuring device. If the specified machine stop time is used, add at least 20% as a safety
factor to account for brake system deterioration. If the stop-time of the two redundant machine control elements is unequal, the
slower of the two times must be used for calculating the separation distance.
3. Th is usually insignificant for purely mechanical switches. However, Th should be considered for safety distance calculation when
using electronic or electromechanical (i.e. powered) hand controls. For Banner Self-checking Touch Buttons (STBs) response time
= 0.02 seconds.
10.5.2 Two-Hand Control Hookup Options
The device is shown not actuated or in the Off state. See ISO 13851 for a complete explanation of “Type” designations and ISO 13849-1
Category requirements.
Dual-Channel (2, 3, or 4 terminals): The drawings show a Type
IIIa Two-Hand Control circuit as described by ISO 13851, and typi-
cally can meet ISO 13849-1 (EN 954-1) Category 1 requirements.
A Type IIIb and Category 3 can be achieved if redundant contacts
from each hand control are used in each channel, i.e., two each in
series, as shown in image D, or with a 3-terminal hookup that uses
pulse monitoring and can detect a short circuit to another source of
power. Both 2- and 3-terminal hookups can detect a short between
channels when the contacts are open if the short is present longer
than 2 seconds. The 4-terminal circuit can detect a short circuit be-
tween channels or to another source of power (image C). 24V
24V
B. A.
C. D.
SC22-3/-3E Safety Controller Instruction Manual
102 www.bannerengineering.com - tel: 763-544-3164 P/N 133487 rev. C