Banner ES-FA-6G Safety Module - Manual (Page 3)

In the United States, the typical level of safety circuit integrity is called control reliability. Control reliability typically incorporates redundant
control and self-checking circuitry and is relatively similar to ISO 13849-1 Categories 3 and 4 (see CSA Z432 and ANSI B11.19).
Perform a risk assessment to determine the appropriate category to make sure that the expected risk reduction is achieved to implement
the requirements described by ISO 13849-1. This risk assessment must also take into account the national regulations, such as U.S.
control reliability or European "C" level standards, to comply with the mandated minimum levels of performance.
WARNING: Safety Categories
The level of safety circuit integrity can be greatly affected by the design and installation of the safety devi-
ces and the means of interfacing of those devices. A risk assessment must be performed to determine
the appropriate safety circuit integrity level or safety category as described by ISO 13849-1 (EN
954-1) to ensure the expected risk reduction is achieved and all relevant regulations and standards
are complied with.
Fault Exclusion
An important concept within the category requirements of ISO 13849-1 is the probability of the occurrence of the failure, which can be
decreased using the "fault exclusion" method. This method assumes that the possibility of certain well-defined failure(s) can be reduced
to a point where the resulting fault(s) can be disregarded.
Fault exclusion is a tool a designer can use during the development of the safety-related part of the control system and the risk assess-
ment process. It allows the designer to eliminate the possibility of various failures and justify it through the risk assessment process to
meet the requirements of Categories 2, 3 or 4. See ISO 13849-1/-2 for further information.
Monitoring of Safety Devices
Requirements vary widely for the level of control reliability or safety category per ISO 13849-1 (EN954-1) in safety applications. While
Banner Engineering always recommends the highest level of safety in any application, it is the responsibility of the user to safely install,
operate and maintain each safety system and comply with all relevant laws and regulations.
Although only applications are listed, the Module can monitor a variety of devices as long as the input requirements are complied with
(see Electrical Installation and Specifications). The Safety Module does not have 500 ms simultaneity between inputs and thus cannot be
used for monitoring a two-hand control. In all cases, the safety performance (integrity) must reduce the risk from identified hazards as
determined by the machine's risk assessment.
WARNING: Emergency Stop Functions
Do not mute or bypass any Emergency Stop device. ANSI B11.19, ANSI NFPA79 and IEC/EN
60204-1 require that the Emergency Stop function remain active at all times.
Emergency Stop Push Buttons and Rope/Cable Pull Switches
The safety inputs can be interfaced with positive-opening switches to monitor an emergency-stop (E-stop) push button or rope/cable pull.
The switch must provide one or two contacts for safety which are closed when the switch is armed. Once activated, the E-stop switch
must open all its safety-rated contacts, and must require a deliberate action (such as twisting, pulling, or unlocking) to return to the
closed-contact, armed position. The switch must be a "positive-opening" (or direct-opening) type, as described by IEC 60947-5-1.
Standards ANSI NFPA 79, IEC/EN60204-1, and ISO 13850 specify additional emergency stop switch device requirements, including the
following:
• Emergency-stop push buttons shall be located at each operator control station and at other operating stations where emergency
shutdown is required.
• Stop and emergency-stop push buttons shall be continuously operable and readily accessible from all control and operating stations
where located. Do not mute or bypass E-stop buttons or rope/cable pulls.
• Actuators of emergency-stop devices shall be colored red. The background immediately around the device actuator shall be colored
yellow (where possible). The actuator of a push-button-operated device shall be of the palm or mushroom-head type.
• The emergency-stop actuator shall be a self-latching type.
For Rope/Cable Pull Installations Only:
• The wire rope should be easily accessible and visible along its entire length. Markers or flags may be fixed on the rope to increase its
visibility.
ES-UA-5A and ES-VA-5A E-Stop Safety Modules
P/N 122365 Rev. E www.bannerengineering.com - tel: 763-544-3164 3