In order to distinguish the differences between these five terms, you need to know what each one means.
ESD (as defined in the previous post) is an acronym for electrostatic discharge. Many times it is used incorrectly as a term for something that is “electrostatic discharge safe.”
The terms anti-static, conductive, and dissipative are all terms that subdivide ESD into more detail. Something insulative is not considered ESD safe.
Materials are divided into these terms based on their individual surface resistance. Surface resistance is a measurement of how easily an electric charge can travel across a medium. Conductive materials are materials that have a surface resistance of less than 1 x 10 5 ohms/square. Dissipative items have a surface resistance of more than 1 x 10 5 ohms/square but less than 1 x10 11 ohms/square.
Anti-static materials are generally referred to as any material which inhibits triboelectric charging. This kind of charging is the buildup of an electric charge by the rubbing or contact with another material. An insulative material is one that has a surface resistance of greater than 1 x 10 12 ohms/square.
There are a few things to keep in mind when choosing an ionizer. First start by deciding which style of ionizer will work best for you. This includes overhead ionizers, desktop ionizers, and gun type ionizers. Then decide on whether or not you would like DC or AC ionization. Each of these choices will narrow your selection from the many available types of ionizers.
Each style of ionizer has its advantages and disadvantages. Overhead ionizers, like the Aerostat Guardian Overhead Ionizer (4004063), are generally the most expensive; however, they save desk space by being hung from above and provide continual ionization over an area. Desktop ionizers, like the 3M 960 Mini Benchtop Ionizer (to the right), are generally the least expensive and still provide continual ionization over an area; however they take away from the desktop space by sitting on the work surface. The third style is the gun type ionizers, like the Simco Top Gun (4005105) below. These are used mainly for pinpoint control of the ionized air flow, and are not used when trying to cover an entire area with ionized air. They work really well as a “blow-off” gun to get rid of dust or other contaminants without using normal shop air which can introduce a charge. The negatives are that they normally require the use of an air compressor which is noisy and fairly expensive. It also doesn’t cover the entire work surface, and without the additional “hands free kits,” you would need to hold it in order to use it.
The difference between DC and AC ionization is the way the emitter points function. In AC, like the Simco Aerostat models, the same emitter point alternates between releasing positive and negative ions. This means they inherently have a voltage balance. This is because if an emitter gets dirty and isn’t functioning, the other emitters are still alternating between positive and negative ions. This also means that the ions are closer together which makes it more likely for them to recombine. This means normally higher fan speeds are needed to reduce the time between the fan and the surface that needs to be ionized. DC ionizers, like the 3M TM960, have separate emitters for positive and negative ions. This means that it’s a little more difficult to ensure a low voltage balance and if one emitter stops working, it throws the unit out of balance. These types of units require a lot more consistent maintenance/monitoring to ensure a good voltage balance. The benefits are that the emitters are separate so there is less of a chance of recombination of the ions. This allows the DC units to operate at a lower fan speed which is very beneficial when your components are small or you are in a clean room.
Soldering, adhesives and laser work are at many times present in an engineeering environment. The fumes and pollution in these work areas usually exceed the safety threshold and put workers at risk. The new WFE 2ES Weller Volume Extraction System is designed to filter 99.5% of these pollutants and help maintain a safe working environment.
Here are a few key features of the WFE & 2ES:
F5-class fine dust filter
Puratex compact H12 filter
Brushless and maintenance-free turbine
Low noise emission
Wide range of accessories
In addition to these features, the WFE 2ES needs no on-site installation by a professional adding to the effeciency of this system.