Rockwell Automation Allen-Bradley GuardShield 450L-B4FNxYD

42 Rockwell Automation Publication 450L-UM001D-EN-P - December 2019
Chapter 4 Safety Function
Figure 15 - Muting Time for Two Sensor T-type Muting Arrangement
For proper operation, MS1 and MS2 must be activated/deactivated within the
time t
sens
, and the light curtain must be clear before the muting time t
Mute
expires.
Muting of the safety light curtain is achieved only when muting sensor MS1 and
MS2 are activated within the specified time t
sens
. Since this muting mode is
bidirectional the muting sequence also functions in reverse (for example, muting
sensor one before muting sensor two, or two before one are both allowed). Both
signals, however, cannot arrive simultaneously (t
sens
minimum). The muting
condition stops if one of the muting sensors is not activated or if the maximum
muting time t
Mute
is exceeded (muting timeout).
The minimum time between the sensors t
sens
minimum is dependent on the
position of the muting sensors and the speed of the object to be muted. You must
maintain at least a delay of t
sens
minimum for more dependable operation.
Tabl e 10
shows the default timing values for T-type muting. These values can be
adjusted by using Connected Components Workbench software.
Table 10 - Two Sensor T-type Muting Default Settings
If t
sens
, t
espe
or t
Mute
is exceeded, the STS and the MUT indicator flashes
(Table 54 on page 118
). The muting lamp output has the same characteristic as
the MUT indicator. If the material is backed away from the sensors, the fault is
cleared and the muting lamp turns off. If the material proceeds to break the light
curtain, the OSSD output turns off. The STS and MUT indicator continue to
flash. Use the muting override command to turn on the OSSD outputs
temporarily and clear the material from the protective field.
Parameter Default Value Parameter Default Value
t
sens
4 s t
mdo
20 s
t
sens
min 50 ms t
espe
5 s
t
Mute
5 minutes
IMPORTANT It must not be possible for a person to pass undetected to the left or right of the
object during the muting process.
ESPE
Muting Sensor S1 (S2)
Muting Sensor S2 (S1)
Mute
t
sens
t
sens
t
espe
t
Mute
t
espe