This safety manual provides information necessary to design, install, verify and maintain a Safety Instrumented Function (SIF) utilizing the Fisher ED, ET, EZ, HP, or HPA valve with 657/667 actuator. Introduction This manual provides necessary requirements for meeting the IEC 61508 or IEC 61511 functional safety standards. Figure 1. Fisher YD Valve with 667 Actuator W2081 Introduction Scope of Manual This instruction manual includes installation, maintenance, and parts information for NPS 1/2 through 8 YD and NPS 1/2 through 6 YS control valves. Refer to separate manuals for instructions covering the actuators and accessories. Instruction Manual D102175X012 EZ-C, ET-C, and EWT-C Valves July 2017 5 Maintenance Valve parts are subject to normal wear and must be inspected and replaced as necessary. Inspection and maintenance frequency depends on the severity of service conditions. This section includes instructions for packing maintenance and trim maintenance. Purpose This safety manual provides information necessary to design, install, verify and maintain a Safety Instrumented Function (SIF) utilizing the Fisher ED, ET, EZ, HP, or HPA valve with 657/667 actuator. Introduction This manual provides necessary requirements for meeting the IEC 61508 or IEC 61511 functional safety standards. Fisher.com Instruction Manual: Fisher EZ easy-e Control Valve PDF Size: 139kb Manuals & Guides Instruction Manual: Trim Cartridge for Fisher ET and EZ easy-e Control Valves PDF Size: 686kb News & Articles Article: Selecting valves for pressure swing adsorption PDF Size: 5.4mb Guide: Sliding-Stem Product Guide | Fisher PDF Size: 115kb