Banner ES-UA-5A Instruction page 6

Safety Input Device Hookup Options
The operation of all dual-channel hookup options is concurrent, meaning that input channel 1 and input channel 2
must be in the same state in both the STOP and RUN condition, but with no simultaneity (i.e. timing) requirement
between the channels.
The dual-channel hookup configuration is able to detect certain failures and faults, such as short circuits, that
could result in a loss of the safety function. Once such a failure or fault is detected, the Safety Module will turn OFF
(open) its safety outputs until the problem is fixed. This circuit can meet ISO 13849-1 Category 2, 3, or 4 requirements,
depending on the safety rating and the installation of the safety input device. This circuit can detect a short circuit
between channels or to another source of power, at a minimum, when the device is actuated.
A single device with redundant outputs that can fail in such a manner to lose the safety function, such as a single
safety interlocking switch, can typically meet only Category 2. See below for means to eliminate or minimize the
possibility of failures and faults that could result in the loss of the safety function(s).
The single-channel hookup configuration can not detect short circuits to secondary sources of +24V dc or detect
the loss of the switching function of the safety input device (i.e., it is not redundant) and thus this circuit typically can
meet only ISO 13849-1 Category 2.
It is recommended that in all circumstances the installation of the Safety Module and its associated safety input devices
are installed to eliminate or minimize the possibility of failures and faults that could result in the loss of the safety
function(s).
Methods to eliminate or minimize 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.
Locating all elements (modules, switches, and devices under control) within one control panel, adjacent to each
other, and directly connected with short wires.
Properly installing multi-conductor cabling and multiple wires through strain-relief fittings. (Over-tightening of a
strain-relief can cause short circuits at that point.)
Using positive-opening components as described by IEC 60947-5-1, installed and mounted in a positive mode.
Periodically checking the functional integrity / safety function and training operators, maintenance personnel, and
others associated with the operation of the machine to recognize and immediately correct such failures.
If you have any questions about your intended use, please contact a Banner applications engineer at the
numbers listed on the last page.
Connection of Multiple Switches
Connect the poles of multiple switches, such as E-
Stop switches, as shown in the following hookup
figures. The switches are shown in the "armed" po-
sition with both contacts closed. Multiple switches
connected to one Safety Module must be series
connected (see figure at right and the warning,
Multiple Switching Devices).
6 Banner Engineering Corp. - Minneapolis, MN USA - www.bannerengineering.com
ES-UA-5A and ES-VA-5A E-Stop Safety Modules
E-Stop E-Stop
S11 S21
Figure 2: Series connection of multiple E-stop switches
Tel: 763.544.3164
S22 S12
P/N 122365 rev. C