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Entry type: FAQ Entry ID: 109761728, Entry date: 10/26/2018

Is it allowed to power an "intrinsically safe" 2-wire transmitter with a standard "non-intrinsically safe" power supply?

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Is it allowed to power an "intrinsically safe" transmitter with a standard "non-intrinsically safe" power supply?


No. You will lose your intrinsically safe certification immediately and irreversibly.

Assuming you need to pre-programm an intrinsically safe 2-wire transmitter and you are currently in a safe area (for example in your workshop) - you might be tempted to power the device with a standard non-intrinsically power supply. But if an intrinsically safe transmitter is connected to a standard power supply, destruction of internal components may occur. As a result, the Ex approval of the transmitter expires. This problem can be avoided by using an intrinsically safe HART isolating power supply, e.g. SITRANS I100 7NG4124-0AA00.

This device is powered by an external power source. At the input the Ex-transmitter is connected.
Via the output (4..20mA signal with HART) the device is programmed on the safe side with a programming tool (wiring see picture).

If you have further questions, please contact our technical support.

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