Banner MMD-TA-11B Muting Modules - Manual (Page 36)

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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
System Installation
Dual-Channel Control
Dual-channel (or two-channel) control has the ability to
electrically extend the safe switching point beyond the FSD
contacts. With proper monitoring (i.e., EDM), this method of
interfacing is capable of detecting certain failures in the control
wiring between the safety stop circuit and the MPCEs. These
failures include a short-circuit of one channel to a secondary
source of energy or voltage, or the loss of the switching action
of one of the FSD outputs. The result could lead to the loss of
redundancy or a complete loss of safety if not detected and
corrected.
The possibility of a failure to the wiring increases as the physical
distance between the FSD safety stop circuits and the MPCEs
increase, as the length or the routing of the interconnecting wires
increases, or if the FSD safety stop circuits and the MPCEs are
located in different enclosures. Thus, dual-channel control with
EDM monitoring should be used in any installation where the
FSDs are located remotely from the MPCEs.
Single-Channel Control
Single-channel (or one-channel) control, as mentioned, uses a
series connection of FSD contacts to form a safe switching point.
After this point in the machine’s safety-related control system,
failures can occur that would result in the loss of the safety
function (e.g., a short-circuit to a secondary source of energy or
voltage).
Thus, this method of interfacing should only be used in
installations where FSD safety stop circuits and the MPCEs are
physically located within the same control panel, adjacent to
each other, and are directly connected to each other; or where
the possibility of such a failure can be excluded. If this can not
be achieved, then two-channel control should be used.
Methods to exclude the possibility of these failures include, but
are not limited to:
• Physically separating interconnecting control wires from each
other and from secondary sources of power.
• Routing interconnecting control wires in separate conduit, runs,
or channels.
• Routing interconnecting control wires with low voltage or neutral
that can not result in energizing the hazard.
• Locating all elements (modules, switches, devices under
control, etc.) within the same control panel, adjacent to each
other, and directly connected with short wires.
• Properly installing multi-conductor cabling and multiple wires
that pass through strain-relief fittings. Over-tightening of a
strain-relief can cause short-circuits at that point.
• Using positive-opening or direct-drive components installed and
mounted in a positive mode.
3.8 Commissioning Checkout
After power is connected to the Muting Module, the EDM has
been properly configured, and the OSSD outputs have been
connected to the machine to be guarded, the operation of the
Muting Module with the guarded machine must be verified before
the combined system may be put into service. To do this, a
Qualified Person must perform the Commissioning Checkout
Procedure described in Section 6.2.