581A Differential Pressure Switch
The 4-1/2 inch diameter scale can be graduated uniformly for DP or level, or square root for direct reading of flow rate. Special scales for indicating liquid quantity in tanks can be provided. A precision, jeweled rotary movement utilizing a thermally stable Ni-Span-C hair spring controls the indicating pointer. Range modifications can be made using the micrometer screw.
Linearity modifications require the scaleplate to be removed for access, while zero and range modifications can be achieved with the scaleplate and pointer in place. Engineered to align with MIL-S-901C Shock Grade A and MIL-STD-167 Vibration criteria, the ® Model 316C 4.5-inch DP Indicator is a distinctive version of the M450C. The U.S. Navy commonly uses this device to determine DP, flow and liquid level for on-board installations.