Banner MMD-TA-11B Muting Modules - Manual (Page 8)

6
P/N 116390 rev. C
Banner Engineering Corp. • Minneapolis, U.S.A.
www.bannerengineering.com • Tel: 763.544.3164
MMD-TA-11B / MMD-TA-12B Muting Module
Instruction Manual
Overview
WARNING . . . Mute on Power-Up
The Mute on Power-Up function should be
used only in applications where:
• Muting the System (M1 and M2 closed) when power is
applied is required, and
• Using it must not, in any situation, expose personnel to
any hazard.
1.13 Mute Lamp Output (ML)
Some applications require that a lamp (or other means) be used
to indicate when the safety device (e.g., light screen) is muted;
the module provides for this (X3−X4; see Caution below). This
indication is selectable between a monitored or a non-monitored
output signal (NPN sinking). The monitored output will prevent
the initiation of a mute after an indicator failure is detected
(current draw falls below 10 mA or goes above 360 mA). If the
application requires compliance with UL 61496, Lamp Monitoring
must be selected and the lamp used must meet applicable
requirements (see Section 3.5.3).
1.14 Backdoor Timer
The Backdoor Timer 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 timer begins when the second muting device makes the
simultaneity requirement (within 3 seconds of the first device),
and will allow a mute to continue for the predetermined time.
After the timer expires, the mute ends – no matter what the
signals from the mute devices indicate. If the MSSI is open,
the OSSD outputs will turn OFF and must be manually reset (if
Module is configured for Manual Reset). The Override function
can be activated (see Section 1.16) to force the OSSDs ON in
order to clear the obstruction.
If the Backdoor Timer expires, a #50 error code will be displayed
until all mute device inputs are open and the MSSI is active
(closed).
The Backdoor Timer can be disabled (i.e., set for infinite time).
See Figure 3-2 and configure DIP switches #7 and #8 for
Backdoor Time-Out OFF.
CAUTION . . . Mute Status Must Be
Readily Observable
Indication that the safety device is muted
should be provided and be readily observable.
Failure of this indication should be detectable and prevent
the next mute, or the operation of the indicator should be
verified at suitable intervals.
Lamp Monitoring must be selected if
the application requires
compliance with UL 61496.
WARNING . . . Backdoor Timer
An infinite time for the backdoor timer (i.e.,
disabling) 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. It is the user’s responsibility to ensure that this
does not create a hazardous situation.
1.15 Mute on Power-Up
Mute Enable must be closed to allow Mute on Power-Up. (See
Warning below.) If selected, the Mute on Power-Up function will
initiate a mute when power is applied, the Mute Enable input is
closed, the MSSI inputs are active (closed), and either M1−M2 or
M3−M4 (but not all four) are closed.
If Auto Reset is configured, the Module allows 10 seconds for
the MSSI and SSI to become active (closed) to accommodate
systems that may not be immediately active at power-up.
If Manual Reset is configured, the first valid reset after the MSSI
and SSI are active (closed) will result in a mute cycle if all other
conditions are satisfied.