Deans Design Services provide Electrical Designs which comply with the latest British Standard Wiring Regulations BS7671 18th Edition Wiring Regulations and subsequent amendments. We provide design of Manufacturers skid units through to bespoke control systems.
We are also able to provide Intrinsically Safe (IS) Calculations where there are specific ATEX requirements. We follow the complete path from the field instrument right the way back to the instrument power supply to determine the maximum resistance within a circuit to avoid the potential of a spark igniting a flammable source.
For more complex designs where repeated reliability is required within a control system loop. We are able to substantiate designs and ensure they are compliant with Functional Safety IEC 61508. Eliminating the risk factor of a potential part of a process from not working correctly. Sometimes this can be overcome by introducing extra test intervals for instrument maintenance, however, usually this means certifying that all devices installed within a circuit meet a specific SIL level where sometimes determines that more than one instrument is required to form part of a SIL certified Loop.
Installing more than one instrument does not necessarily a negative impact on a CAPEX budget as this can be overcome by reducing the downtime of a process plant when a second or third instrument is installed. For example, a failure of one instrument may not stop the process plant provided the readings from the other instruments are providing sensible measuring limits and within the process operating parameters for high and low alarm/trips.