Ex zones are places where there is an explosive atmosphere and any spark or overheating can result in an explosion with catastrophic consequences. Because of this, particular attention must be paid to the selection of equipment to be used in explosive atmospheres. In this blog post, you will find out, among other things, what the intrinsic safety standards are and which equipment meets them.
Intrinsic safety is an approach to the design of electrical equipment that prevents explosions by ensuring that the energy (e.g. electrical sparks, hot surfaces) transmitted to the hazardous area is significantly less than the energy required for an explosion hazard.
Intrinsic safety is a required standard for devices that are used in highly volatile areas that may include flammable gases, powders or fuels.
Taking care to meet intrinsic safety standards in industry is an important part of protecting people, installations and products from risk. High-quality measurement and control technology has a preventive function in industrial systems.
Intrinsic safety is an approach to the design of electrical equipment that prevents explosions by ensuring that the energy (e.g. electrical sparks, hot surfaces) transmitted to the hazardous area is significantly less than the energy required for an explosion hazard.
Intrinsic safety is a required standard for devices that are used in highly volatile areas that may include flammable gases, powders or fuels.
Taking care to meet intrinsic safety standards in industry is an important part of protecting people, installations and products from risk. High-quality measurement and control technology has a preventive function in industrial systems.
In the area of intrinsic safety, many myths have grown up and many mistakes are made. So we outline some of the most important requirements you need to bear in mind:
Adding an IS interface does not make a device intrinsically safe. Reducing the risk of explosion can only be achieved by installing equipment that has been specifically designed to meet IS requirements, together with a suitable IS interface.
Pay attention to the cables! Because cables have inductance and capacitance, and thus energy storage capacity, they can affect the safety of the system. It is important that the capacitance and inductance of the cable and field devices are less than the capacitance and inductance allowed for the IS interface for the gas group in which the device is installed. It is usual to calculate the maximum cable length allowed for the installation.
The first check should be carried out shortly after installation of the appliance. Thereafter, regular periodic checks should be carried out throughout its lifetime. This is to detect damage or unapproved replacement of IS components.
Explosion-proof equipment is capable of stopping an explosion inside an enclosure so that flames or hot gases do not escape. The term "explosion-proof" does not mean that the product is able to withstand a strong external force.
Intrinsically safe electronic devices, on the other hand, are low enough in power that they will not cause an explosion.
avoidance of the cost, size and laborious installation of explosion-proof enclosures
maintenance and diagnostic work can be carried out without shutting down production and ventilating the area
potentially lower insurance premiums due to reduced risk
JUMO offers instruments in intrinsically safe design. These instruments are approved for use in hazardous areas.
The JUMO Ex-i isolated switching amplifier provides reliability, galvanic isolation and safe transmission of switching signals in a wide range of applications. It can be installed in Ex zone 2 and used with a sensor in zone 0.
Safe transmission of switching signals even from Ex areas
High degree of process reliability due to intrinsically safe inputs, three-way galvanic isolation and line fault detection
Space saving in the control cabinet due to the two-channel version
Reduced storage costs due to wide permissible supply voltage range
Reduced start-up time due to screw terminals and simple configuration via DIP switches
ATEX and IECEx approval, installation possible in zone 2, sensor in zone 0
Extended ambient temperature range from -40°C to 60°C
JUMO offers the optimum complement for the reliable transmission of level information - the JUMO NESOS series.
JUMO intrinsically safe temperature and humidity sensors are designed for demanding industrial applications where stable measurements and the ability to adapt the device to the application are required.
measurement over the entire range from 0 to 100% RH
temperature resistant up to 180°C (depending on probe type)
pressure resistant up to 100 bar (depending on probe type)
robust metal housing
degree of protection IP65
exceptional accuracy and stability
graphical trend display and measurement history for the last year
possibility to retrieve data from NIST
options: calculation and output of dew point, absolute humidity, mixing coefficient, wet thermometer temperature, enthalpy and vapour pressure
