I have a intrinsically safe positioner in non-hazard area. if I don't use I.S barrier in the control system what will be happened?
The device, the positioner, will not be protected from electrical faults in the safe area that could create arcing/sparking conditions in the positioner.
It will function OK as a positioner, just not as an I/S positioner.
The intrinsic safety is only achieved when the loop is engineered for I/S and all the I/S parts are present and wired according the control drawing.
Your installation is not an intrinsically safe loop. It is just have a positioner with an I/S approval label.
If the device is not in a classified area, it does not matter if it has barriers or not.
If the positioner located at Non-Hazardous area then no issue, the device still can work properly without IS Barrier
>I have a intrinsically safe positioner in non-hazard area.
>if I don't use I.S barrier in the control system what will
Nothing, it will work as a positioner in a non hazardous general purpose area.
Most instruments these days are designed for IS, explosion proof and NEMA 4 general purpose service. The supplier only needs to stock one device and the user can wire it as IS, explosion proof or GP.