- Single Station Continuous Dual-Wire Monitor
Continuously monitors the ground integrity and charge generation of one operator and supervisor as well as the ground integrity for one ESD worksurface and one optional tool, eliminating the need for periodic testing and record keeping of wrist straps
- Patented* Dual Polarity Technology
Provides Real-Time Continuous Monitoring for Operator Path-to-Ground and Presence of 1 Meg Resistor True continuous monitoring (versus pulsed) instantaneously detects broken cords, intermittent faults, dry skin, loose bands and low resistance.
- Dual Polarity Technology
Steady-State DC Dual Polarity Signal yields virtually zero voltage on the operator
- Operator Charge Detection Alarm
Alarms if the operator generates or comes in contact with a voltage that would be dangerous to an ESD susceptible item
- RS-485 Communication Ports
Use with EMIT SIM Software for test data acquisition and management
- User Adjustable Features
Use the internal DIP switches to enable / disable test circuits and modify the operator test voltage, operator charge detection voltage and worksurface resistance limit
- NIST Calibrated with Certificate
Calibrated with accepted procedures and standards traceable to the National Institute of Standards and Technology. For more information on calibration of EMIT products see Calibration
|50579||ZVM Solo, Europe||$334.97|
“A properly grounded wrist strap will keep a person’s body voltage to approximately + 10 V. The main advantage to a constant [or continuous] monitor is the immediate indication that the employee receives if the wrist strap falls open. With an unmonitored system, the employee will not be aware of a wrist strap failure until the start of the next shift. This has reliability benefits for an ESD program as it might help reduce or eliminate ESD damage.
There are also other process benefits from using constant monitors such as the elimination of the need to maintain daily test logs and a reduction in the time for employees to make the daily test. For units that also monitor the connection of a work surface to protective earth, it is also possible to reduce or eliminate the checking of the work surface as part of the periodic audit of the process.
Constant monitors might be implemented by an organization due to high reliability requirements imposed by customers.” [CLC/TR 61340-5-2:2008 User guide Annex B.1.3 Constant monitors]
*US patents 6,052,053 and 6,205,408
Our thanks to Conformity Magazine Published in December 2004 issue
Accurate process evaluation provides real answers
Provided by the ESD Association
by Stephen Halperin, in collaboration with Ron Gibson
“We need to spend HOW MUCH?”
Recently, a company experienced several large losses due to electrostatic discharge (ESD) and had a very unhappy customer on their hands. The manufacturing vice president now faced a substantial expenditure for new ESD loss prevention equipment. The company’s first step had been to hire an ESD consultant who recommended the purchase of several thousands of dollars in ionization equipment and monitoring instruments for several of the company’s facilities.
The troubled VP read the report several times looking for justification of the expense. However, the report did not define how the recommended equipment would meet the VP’s specific needs. Other than describing how ionization reduced electrostatic charge after it is generated and that the instruments could confirm that a discharge occurred, the report did not identify the actual cause of the process problem. No ESD measurements were described. There were no details related to cause of product loss, device sensitivity concerns, value issues, process and handling details, examination and description of existing controls, or rationale for how the recommended tools would solve the problem in question. The report was clearly based on the consultant observing the process of a single manufacturing environment. In effect, the report made a purchasing recommendation based on a “blanket” opinion, not on facts specific to the needs of the company or their customer. Such an approach typically makes a bad situation worse. While the recommended tools may have been very useful for investigating a process or for solving defined problems, they are expensive Band Aids“ when used in undefined problem situations.
Today’s electronic manufacturing environment demands that minimal ESD controls be in place to provide fundamental protection for electrostatic discharge sensitive (ESDS) devices. When basic ESD controls are employed and losses still occur, manufacturing and quality managers face more difficult problems., In assessing the problem, companies struggle with a variety of major questions concerning a specialized technology, while having minimal information and available skills. To avoid the risk of making the wrong investment decision without solving the initial problem, management needs a way to select and implement the most effective ESD controls that fit their financial situation, solve their specific problems, and provide a respectable return on their investment.
To continue reading Enhancing Profits with Effective ESD Control Click Here
ANSI/ESD S20.20 Foreword states:
- “This standard covers … electrical or electronic parts, assemblies and equipment susceptible to damage by electrostatic discharges greater than or equal to 100 volts Human Body Model (HBM).”
- “When handling devices susceptible to less than 100 volts HBM, more stringent ESD Control
Program Technical Requirements may be required, including adjustment of program Technical
Element Recommended Ranges.”
HMB Classification Class 0 is:
Per ESD-STM5.1 Human Body Model (HBM) Table 1 Class 0 has ESD Voltage Range < 250 Volts
Basically, to control the environment to decrease the probability of ESD damage in “Class Zero”
situations, involves increasing ESD protective redundancies and periodic verifications to those ESD
Control technical elements.
- Personnel: Decrease Wrist Strap and ESD Footwear upper limit permitted (The ESD Association has test data showing charge on a person is less as the path-to-ground resistance is less) The use of continuous monitors, smocks, use / increased use of ESD flooring, sole or full coverage foot grounders (HBM & CDM)
- Worksurfaces: Dissipative (CDM) i.e. change < 10^9 to a requirement of 10^6 to 10^8 ohms
- Bonded grounds – Carts, shelves, equipment
- Conductors: Minimizing isolated conductors like devices on PC Boards (CDM)
To see examples of Wrist Straps capable of dealing with class zero environments Click Here
To see examples of Grounding Cords capable of dealing with class zero environments Click Here
Minimize Charge Generation
The best form of control is to minimize charge generation. Grounding and ionization eliminate charges once generated. Shielding protects from generated charges.
- Personnel – Low Charging floor finish
- Surfaces – Use of low charging (anti-static) topical treatments
- Eliminate as best as possible all non-process necessary insulators
- Topically treat where ever possible insulators that cannot be removed
- Consider use of ESD Chairs or treat to reduce charge generation
- Shield charges on clothing by using ESD Smocks
To continue reading ESD Control Program Considerations when Dealing with
Class Zero Items Click Here