Overview, Installation and alignment, Warning – Banner EZ-SCREEN Low-Profile Safety Light Curtain Systems User Manual

Page 24: Notice regarding mpces

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22

P/N 133487

Banner Engineering Corp.

Minneapolis, U.S.A.

www.bannerengineering.com • Tel: 763.544.3164

Overview

22

P/N 140044 rev.

E

Banner Engineering Corp.

Minneapolis, U.S.A.

www.bannerengineering.com • Tel: 763.544.3164

EZ-SCREEN LP

Instruction Manual

Installation and Alignment

The safety (separation) distance formula for U.S. applications:

Ds = K x (Ts + Tr) + Dpf

where:
Ds – the safety distance, in mm (inches);
K – 1600 mm per second (or 63" per second), the OSHA1910.217,

ANSI B11, ANSI/RIA R15.06 hand-speed constant (see Note
1);

Ts

– the overall stop time of the machine (in seconds) from the

initial “stop” signal to the final ceasing of all motion, including
stop times of all relevant control elements (e.g., interface
modules) and measured at maximum machine velocity (see
Note 2 and Warning on page 21).

Tr – the maximum response time, in seconds, of the EZ-SCREEN

LP emitter/receiver pair (depending on model); and

Dpf – the added distance due to depth penetration factor as

prescribed in OSHA1910.217, ANSI B11, ANSI/RIA R15.06 for
U.S. applications (see Warning):

NOTES:
1. The OSHA-recommended hand speed constant K has been determined by various

studies, and although these studies indicate speeds of 63"/second to more than 100"/
second, they are not conclusive determinations. 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 machine manufacturer’s

specified stop time is used, add at least 20% to allow for possible clutch/ brake
system deterioration.
This measurement must take into account the slower of the two
MPCE channels, and the response time of all devices or controls that react to stop the
machine. See Notice Regarding MPCEs.

If all devices are not included, the calculated

safety distance (Ds) will be too short and serious injury could result.

Example: U.S. Applications, Model SLSP14-550

K = 63" per second (the hand speed constant set by OSHA)
Ts = 0.32 (0.250 second specified by machine manufacturer; plus

20% safety factor; plus 20 ms interface module response)

Tr = 0.0165 second (the spec i fied SLSP14-550 response time)
Dpf = 3.6" (14 mm resolution, Reduced Resolution ON)
Sub sti tute the numbers into the for mu la as fol lows:

Ds = K x ( Ts + Tr ) + Dpf

Ds = 63 x (0.32 + 0.0165) + 3.6 = 24.8"

Mount this EZ-SCREEN LP emit ter and re ceiv er so that no part of
the defined area will be closer than 24.8" to the closest reachable
hazard point on the guarded ma chine.

Notice Regarding MPCEs

Each of the machine primary control elements (MPCE1

and MPCE2) must be capable of immediately stopping

the dangerous machine motion, regardless of the state of

the other. The two machine control channels need not be

identical, but the machine’s stop time performance (Ts,

used to calculate separation distance) must be based on

the slower of the two channels (see Section 3.5.3).

Reduced

Resolution

Depth Penetration Factor (Dpf)

14 mm Systems

25 mm Systems

OFF

24 mm (0.94")

61 mm (2.4")

ON

92 mm (3.6")

915 mm (36")

The minimum distance formula for European applications:

S = (K x T) + C

where:
S – the minimum distance, in mm, from danger zone to light screen

center line; minimum allowable distance is 100 mm (175 mm for
non-industrial applications), regardless of calculated value.

K – hand-speed constant (see Note 1);

2000 mm/s (for minimum safety distances ≤ 500 mm)
1600 mm/s (for minimum safety distances > 500 mm)

T

– the overall machine stopping response time (in seconds), from

the physical initiation of the safety device and the machine
coming to a stop (or the hazard removed). This can be broken
down into two parts: Ts or Tr, where T = Ts + Tr

Ts

– the overall stop time of the machine (in seconds) from the initial

“stop” signal to themachine coming to a stop (or the risk being
removed), including stop times of all relevant control elements
(e.g., interface modules) and measured at maximum machine
velocity (see Note 2 and Warning on page 21).

Tr – the maximum response time, in seconds, of the EZ-SCREEN

LP emitter/receiver pair, depending on model; and

C – the additional distance, in mm, based on intrusion of hand or

object towards danger zone prior to actuation of a safety device.
Calculate using the formula: C = 8 x (d – 14) where d is the
resolution of the device (for d < 40 mm) or use 850 mm for C.

NOTES:
1. The recommended hand speed constant K, derived from data on approach speeds of the

body or parts of the body, as stated in ISO 13855.

2. Ts is usually measured by a stop-time measuring device. If the machine manufacturer’s

specified stop time is used, add at least 20% to allow for possible clutch/ brake
system deterioration.
This measurement must take into account the slower of the two
MPCE channels, and the response time of all devices or controls that react to stop the
machine. See Notice Regarding MPCEs.

If all devices are not included, the calculated

minimum distance (S) will be too short and serious injury could result.

Example: European Applications, Model SLSP14-550

K = 1600 mm per second
T = 0.32 (0.250 second specified by machine manufacturer; plus

20% safety factor; plus 20 ms interface module response), plus
0.0165 second (the spec i fied SLSP14-550 response time)

C = 8 x (34-14) = 160 mm (14 mm resolution, Reduced Resolution ON)
Sub sti tute the numbers into the for mu la as fol lows:

S = ( K x T ) + C

S = (1600 x 0.3365) + 160 = 698.4 mm

Mount this EZ-SCREEN LP emit ter and re ceiv er so that no part
of the defined area will be closer than 698.4 mm to the closest
reachable hazard point on the guarded ma chine.

WARNING . . .

Determine Correct Stop Time

Stop time (Ts) must include the response time of all devices
or controls that react to stop the machine
. If all devices are not
included, the calculated safety/minimum distance (Ds or S) will be
too short. This can lead to serious bodily injury or death. Be sure
to include the stop time of all relevant devices and controls in
your calculations.

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