Most intelligent transmitters also provide for the tag number to be programmed into its electronics-known as a soft tag - so the transmitter is capable or responding to an inquiry sent via the control system or a communicator. This is very useful during commissioning and troubleshooting to enable easy verification of the identity and/ or integrity of each control loop and the functionality of every transmitter. Safety Certified transmitters have a distinctive yellow tag affixed. Figure 3.1.13b