Banner SC26-2 Series, Инструкция по эксплуатации

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Mute
Enable
ON or OFF
Safety
Input
Mute Sensor
Pair
Safety
Output
Figure 33. Timing logic—One mute sensor pair with mute enable
Simultaneity Timer Reset Function
The Mute Enable input can also be used to reset the simultaneity timer of the mute sensor inputs. If one input is active for
longer than three seconds before the second input becomes active, the simultaneity timer prevents a mute cycle from
occurring. This could be due to a normal stoppage of an assembly line that may result in blocking one mute device and the
simultaneity time running out.
If the ME input is cycled (closed-open-closed) while one mute input is active, the simultaneity timer is reset, and if the
second mute input becomes active within three seconds, a normal mute cycle begins. The function can reset the timer only
once per mute cycle (all mute inputs M1-M4 must open before another reset can occur).
Bypass
An optional Bypass/Override Mode may be enabled by checking the BP (Bypass) box in the Muting Block properties
window. There are two available Bypass/Override Modes—Bypass and Mute Dependent Override. The Bypass mode is
used to temporarily bypass the safeguarding device to keep on or turn on the output of the function block. The Mute
Dependent Override mode is used to manually override an incomplete mute cycle (for example after the mute time limit
expires). In this case, one or more mute sensors must be activated while the safeguard is in the Stop state to initiate the
override.
Mute Lamp Output (ML)
Depending on a risk assessment and relevant standards, some applications require that a lamp (or other means) be used
to indicate when the safety device, such as a light screen, is muted. The Safety Controller provides a signal that the
protective function is suspended through the Mute status output.
Important: Mute Status Indication
Indication that the safety device is muted must be provided and be readily observable from the location
of the muted safety device. Operation of the indicator may need to be verified by the operator at
suitable intervals.
Muting Time Limit
The muting time limit allows the user to select a maximum period of time that muting is allowed to occur. This feature
hinders the intentional defeat of the muting devices to initiate an inappropriate mute. It is also useful for detecting a
common mode failure that would affect all mute devices in the application. The time limit can be adjusted from 1 second to
30 minutes. The mute time limit may also be set to Infinite (disabled).
The timer begins when the second muting device makes the simultaneity requirement (within 3 seconds of the first
device). After the timer expires, the mute ends despite what the signals from the mute devices indicate. If the input device
being muted is in an Off state, the corresponding Muting Block output turns off.
WARNING: Muting Time Limit
An infinite time for the Muting Time Limit should be selected only if the possibility of an inappropriate or
unintended mute cycle is minimized, as determined, and allowed by the machine’s risk assessment. The
user is responsible to make sure that this does not create a hazardous situation.
Mute Off-Delay Time
A delay time may be established to extend the Mute state up to the selected time (1, 2, 3, 4, or 5 seconds) after the Mute
Sensor Pair is no longer signaling a muted condition. Off-delay is typically used for Safety Light Screen/Grid workcell "Exit
Only" applications with mute sensors are located only on one side of the defined area. The Muting Block output will remain
On for up to 5 seconds after the first mute device is cleared, or until the muted Safety Input device (Mute Block In) returns
to a Run state, whichever comes first.
XS/SC26-2 Safety Controller
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