The Barton Model 247 bellows within the DPU move in response to changes in the differential pressure measured at the primary device installed in the process system. Movement of the bellows of the Barton model 247 is mechanically transferred to the indicator mechanism which in turn positions the indicator pointer.
The DPU torque tube shaft of the Barton Model 247 is connected to the drive arm of the indicator mechanism. The torque tube shaft rotates in response to DPU bellows movement and this rotation is mechanically transmitted through the drive arm and associated mechanism to position the pointer on the scale to the indication relative to the differential pressure measured by the DPU.
Changes in pressure within the Differential Pressure Unit pressure housings cause the DPU bellows of the Barton model 247 to move in the direction of the decreasing pressure. Movement of the bellows of de Barton 247 model is transferred to the DPU torque tuube output shaft. The Torque tube shaft is the mechanical output of the DPU which is attached to the back of the indicator case. The torque tube shaft is connected to the indicator mechanism.