ESD Control Selection Guide Choose from Our Extensive Range of Grounding Accessories, Packaging, Clothing and ESD Control Equipment
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ESD Control Selection Guide Choose from our extensive range of grounding accessories, packaging, clothing and ESD control equipment uk.rs-online.com November 2017 Introduction ESD Control Selection Guide INTRODUCTION Many electronic components and assemblies used in high technology products As industry experts, we offer an extensive selection of Electrostatic discharge can be damaged or degraded by the sudden exchange of static electrical charges. control equipment for any workplace environment. Brands range from RS Pro, our This Electrostatic Discharge, or ESD, is the reason industries handling susceptible high quality, professionally approved own range, to SCS, Charleswater, Menda, electronic components must take steps to minimise ESD risk. EMIT, Electrolube, Vermason and other market-leading brands. WHAT IS ESD AND WHAT ARE ITS RISKS? WHY ESD CONTROL? ESD STANDARDS When two items are at different levels of electrostatic As electronic technology EN 61340 Part 5-1: Protection of charge, i.e. one positively and one negatively charged, advances, electronic circuitry electronic devices from electrostatic they will want to come into balance. If the items are in gets progressively smaller. phenomena is the standard most close enough proximity there can be a rapid, spontaneous As the size of components is companies use to build their ESD control transfer of electrostatic charge from one to the other. This reduced so is the microscopic plan. is called Electrostatic Discharge or ESD. spacing of insulators and circuits within them. The standard uses a Human Body Model ESD is the hidden enemy in a high-tech manufacturing Their sensitivity to ESD is to simulate discharges from a person and increasingly environment. Modern electronic circuitry can be burned or increased. tests an electronic device at higher and higher discharges melted when subject to an ESD event which is, in effect, a until it fails. This establishes the device’s withstand voltage. miniature lightning bolt. To protect sensitive electronic components and circuitry, ESD protection should be considered whenever and Two types of risk to electronic equipment can occur: wherever you handle the items. This includes throughout the manufacturing, test, shipping, handling or operational ESD SENSITIVE COMPONENTS Catastrophic failure processes, and during field Catastrophic failure causes a The electronic components in the chart below can be service operations. permanent fault. The ESD event damaged by the electrostatic voltages shown. may have caused a metal melt, Voltage Rating junction breakdown or oxide failure. ESD Class Device Names (V) Normal inspection is able to detect a catastrophic failure. SAW, JFETS, CCDs, Precision voltage regulator diodes, OP Class 0 0 to 99 AMP, Thin film resistors, Integrated circuits, Hybrids utilizing class 1 parts, VHSI, CSCRs. Latent defect A latent defect is linked to an ESD SAW, JFETS, CCDs, Precision voltage regulator diodes, OP Class 1 200 to 1,999 AMP, Thin film resistors, Integrated circuits, Hybrids utilizing event that causes partial degradation. class 1 parts, VHSI, CSCRs. This defect may not be detected by JFETs, Ics, VHSIC, Precision resistor networks (type RZ), normal inspection and the device can Class 2 2,000 to 3,999 continue to perform as it should. The Hybrids utilizing class 2 parts, Low power bipolar transistors. defect can then cause intermittent or JFETS, OP AMPS, Ics, All other microcircuits not included in class 1 or 2, Small signal diodes, General purpose silicon permanent failure at a later time. Class 3 4,000 to 15,999 rectifiers, Opto-electronic devices (LEDs, phototransformers, opto couplers), Resistor chips, Piezo electric crystals, Hybrids using Class 3 parts. Discover more at uk.rs-online.com 2 Introduction ESD CONTROL PLAN How to set up an ESD control plan in your company Any business working with ESD sensitive items should set up ESD prevention and control measures in the form of a Control plan, according to EN 61340 Part 5-1 (see page 2). Every company will have different processes so each will require its own plan. Steps to set up your Control plan are as follows: Define what you are trying to protect Establish and identify your ESD Implement a Compliance Verification 1 Identify any ESD susceptible items that your 5 Protected Area (EPA) 9 plan company handles. Treat any device that you Define all departments which will be EPAs. Document the steps you will take to review, receive in ESD packaging as a susceptible item. Identify and control access using signs, floor verify, analyse, evaluate and improve your ESD marking and access control measures. programme. Compliance verification records (See page 3 for more). should be kept. Become familiar with the industry 2 standards for ESD control Read BS EN 61340-5-1 for guidance if you Select ESD control products to use in Develop a Training plan manufacture, process, assemble, install, 6 your EPA 10 Your training plan should specify how package, label, service, test, inspect, transport Consider products such as work surfaces, personnel who handle or contact ESD sensitive or handle susceptible items. flooring, seating, ionisation, shelving, trolleys items will undergo training in ESD awareness and clothing. and prevention. Select a grounding/equipotential 3 bonding system Develop a Packaging plan for materials Make the ESD Control plan part of your Eliminate differences in potential in your ESD 7 handling and storage 11 internal quality system protected area by connecting ESD control When moving ESD susceptible devices Your ESD control plan should include a list elements and personnel to a protective outside a protected area, what packaging will of ESD control items used in the EPA, the earth, functional earth or an equipotential you use? Compliance Verification plan and the bonding system. Training plan. Use proper markings for ESD Determine a personnel grounding 8 susceptible items, system or packaging 4 method for operators Seated operators must use a wrist strap, however standing workers can use a foot grounding system. In some cases both grounding methods will be used. ESD ESD Susceptibility symbol Protective symbol Discover more at uk.rs-online.com 3 Introduction ESD Control Selection Guide ESD PACKAGING, STORAGE AND ESD PERSONAL GROUNDING & CONTENTS 1 STATIONERY 4 ESD CLOTHING 7 ESD FURNITURE ESD packaging and Wrist straps and Equip your ESD protected area with storage products foot grounders are suitable ESD safe workbenches, protect ESD used to ground chairs and trolleys to minimise risk sensitive items from people in an ESD from items of furniture. electrostatic fields protected area. and electrostatic Workbenches ............................................... Page 40 discharges. Chairs ........................................................... Page 40 Trolleys and Carts ....................................... Page 40 Wrist Straps ..................................................Page 27 ESD GROUNDING ACCESSORIES, Bags .................................................................Page 6 Wrist Straps & Cords .................................. Page 28 8 BRUSHES AND PROBES Bins & Boxes ....................................................Page 9 Cords ............................................................ Page 29 Foam, Film & Wrap .......................................Page 11 Toe & Heel Straps ........................................ Page 30 Earth Bonding points, cords and Tape ............................................................... Page 13 Lab Coats & Shirts ....................................... Page 31 snaps are used to link objects and Cabinets, Drawers & Inserts .......................Page 15 Security Identification adgesB .................. Page 31 people inside an ESD protected Wall Panels, Racks, Posts & Kits ..................Page 17 Gloves ........................................................... Page 32 area to ground. Brushes and other Office Supplies & Stationery ...................... Page 18 Safety Shoes & Boots ................................. Page 33 accessories aid risk free working. Over Shoe Overs ......................................... Page 33 Grounding Accessories .............................. Page 42 Brushes ......................................................... Page 45 Probes........................................................... Page 46 ESD TESTING AND MONITORING 2 EQUIPMENT 5 ESD MATTING ESD protection systems need to be ESD TREATMENTS, LOTIONS AND checked on a regular basis. This is an ESD matting removes 9 DISPENSERS important requirement of the electrostatic charges from ESD Standard. conductors that are placed ESD safe dispensers are dissipative Test Meters ................................................... Page 20 on the surface. and designed to protect valuable static sensitive printed circuitry. Continuous Monitors ...................................Page 22 Matting ......................................................... Page 35 Testers and Auditiors....................................Page 22 Treatments & Lotions ................................... Page 48 Dispensers ................................................... Page 49 ESD FIELD SERVICE IONISERS 6 3 ESD LABELS & POSTERS Field service kits offer the 10 Eliminate both negative and positive electronics field service charges on items that cannot be technician a simple and ESD labels and signs are required to grounded. effective means of creating properly mark ESD susceptible items inside of packaging and to identify the Ionisers ..........................................................Page