Where as low cost Temperature Transmitters for example like RTD / TC to current converters are available in the market, OSNA designs basically signal converters with 3 point galvanic isolation between the 24 V DC power supply circuit, RTD /TC signal and between the 4-20mA current flowing to the DCS(Decentralized Control System) / to the control room. Even the 24 V DC supply powering the unit, isolated through the Inverter Technology to avoid any short circuit destroy the sensor located in the safe area. Of course the same isolation will stop a short circuit from travelling from a relative low cost sensor to the much more expensive DCS. This three point isolation requires costly ferrites with hardly any iron losses to allow a perfect linearity between the field sensor value and the result and Signal flowing to the control room. The trend towards achieving a lower stock level of isolator Units and therefor the end user shall wish to order out more universal units where the inputs and outputs can be field selected and their range also be changed. This has resulted in the OSNA microprocessor based signal convertors, where a more detailed planning in the measurement loops was possible, the result is: lower cost versions which are factory settable. OSNA undertakes to design also customized Special Interfaces ATEX approved like Current multipliers in similar OS series housing.