Enabling Switches ZS - EUCHNER GmbH + Co. KG - #5

Text version of the page

Untitled table.main {} tr.row {} td.cell {} div.block {} div.paragraph {} .font0 { font:5.00pt "Arial", sans-serif; } .font1 { font:6.00pt "Arial", sans-serif; } .font2 { font:7.00pt "Arial", sans-serif; } .font3 { font:7.20pt "Arial", sans-serif; } .font4 { font:9.00pt "Arial", sans-serif; } .font5 { font:10.00pt "Arial", sans-serif; } .font6 { font:15.00pt "Arial", sans-serif; } .font7 { font:21.00pt "Franklin Gothic Medium", sans-serif; } .font8 { font:41.00pt "Georgia", serif; } General EUCHNER Standards and approvals Standards Enabling switches that are integrated into safety circuits have a safety function. For this reason they are assessed based on the Machinery directive and the European standards. The Machinery directive has been implemented in national law in the EU member states and, as a result, is binding for all manufacturers. Detailed requirements for switches are defined in EN 60947 Part 5-1 (Specifica­tion for low-voltage switchgear and controlgear. Part 5-1: Control circuit devices and switching elements. Electromechanical control circuit devices). If the requirements of these standards are met, conformity with the applica­ble laws and therefore with the Machinery directive is assumed. EUCHNER enabling switches comply with the relevant standards for safety switchgear and therefore help you to comply with safety requirements during the de­sign of your machinery. User standards As a user, you should take into consideration the following standards of relevance for enabling switches: European and international standards Function and technology used in enabling switches Task of enabling switches Enabling switches are manually operated control devices that, together with other control switches, enable commands related to potentially hazardous conditions to be run, as long as the enabling switches are actuated continuously. These switches are used wherever operating personnel must work directly in the danger area on machines and systems. This is necessary, e. g. during setting up, programming, testing or servicing work. As per annex 1 of the Machinery directive, the protective action of movable safety guards can be disabled in these operating modes. The Machinery directive places the condition that these operating modes must be secured using a lockable device (e. g. key-operated switch) and machine operation is only allowed to be triggered by a second, separate action. To enable the operator in the danger area of a machine to trigger a machine movement, an enabling device must additionally be actuated. The operator must also be able to stop the machine movement using the enabling device. This task is performed by the enabling switch. Every person who is in the hazardous area must carry an enabling device so that suitable action can be taken in case of danger. Two-stage or three-stage enabling switch? The operator can only start a machine movement if he/she actuates the enabling switch and keeps the switch in the actuated position. The movement is stopped again when the switch is released. This two-stage function (OFF-ON) is provided by all enabling switches. However, experience shows that the operator often clenches the enabling switch in an emergency. In this case a three-stage enabling switch is better and is specifically requested in many C standards. This switch has three switch positions (OFF-ON-OFF) and, if the operators clenches the switch, it is actuated beyond the enabling position (middle position) and the machine is shut down as a result. If a 2-stage enabling switch is used, it must also be ensured that, in an emergency, the operator is in a position to activate an emergency stop device in close proximity (VDI 2853). To identify the type of enabling switch in the catalog, the following symbols are used: Standard Title EN 60 204 Safety of machinery. Electrical equipment of machines EN 775/ EN ISO 10218 Robots for industrial environments - safety require­ments (ISO 10218:1992, modified) VDI 2853 Safety related requirements on design, configuration and operation of industrial robots (withdrawn) VDI 2854 Safety related requirements on automated manuf-acturing systems American standards Standard Title ANSI B11-TR3-2000 Risk Assessment and Risk Reduction - A Guide to Estimate, Evaluate and Reduce Risks Associated with Machine Tools NFPA 79 (2002) Electrical Standard for Industrial Machinery OSHA 29 CFR 1910 Subpart O Subpart P Subpart S Machinery and Machine Guarding Hand and Portable Power Tools and Other Hand- Held Equipment Electrical Please also observe any existing C standards! Approvals To demonstrate conformity, the Machinery directive also includes the possibility of type examination. In addition to taking into account all relevant standards, EUCHNER commissions type examinations by a notified body. Many of the enabling switches listed in this catalog have been tested by an emplo-yers' liability insurance association (BG) and are given in the lists from the BG. Furthermore, many enabling switches are listed by the Underwriters Laboratories (UL) and the Canadian Standards Association (CSA). These enabling switches can be used in countries in which this listing is required. The approval symbols on the individual pages of the catalog indicate which body tested the enabling switches. With the aid of the approval symbols listed below you can quickly see which approvals are available for the related enabling switches: Large selection of switching elements To be able to cover as many applications as possible, EUCHNER enabling switches can be fitted with various switching elements of single-channel or dual-channel design. Auxiliary contacts are also available, as are ad-ditional switches or displays. Positively driven contacts Q Positively driven contacts are used in many switching elements. These are special contact elements that are designed to ensure the switching contacts are always reliably separated. Even if contacts are welded together, the connection is opened by the actuating force. e(E)iis LISTED Switches with this symbol are approved by an employers' liability insurance association (Berufsgenossenschaft, BG) Switches with this symbol are approved by Underwriters Laboratories (UL, Canada and USA) Subject to technical modifications; no responsibility is accepted for the accuracy of this information. 5 EUCHNER