580A Differential Pressure Switch
The 580A display is available in three designs: • Switch (Model 580A-0). This model, with a thick thin plate glass filter, provides a definite indication of difference in the two regulated stress. Blind switch (580A-2 model). This model provides a powerful metal cap and no graphical indication of differential stress. Switch Blind Interior Indicator. Unlike the model showing the lens, there is no visually noticeable indication. However, inside components are the same as Model 580A-0. When the flap is raised, a client can use the internal sensor to determine the DPU input stress when changing the setpoints of the buttons. For elevated heat, the Model 580A utilizes two separately variable single-pole double-throw (SPDT) snap-acting buttons.
Both sides of the switches are linked, enabling both standard open and standard closed applications to be supported by the switches. Direct-set change links are versatile over a nominal range of 10-90%. Switches and modifications are readily accessible when the cover is removed. The 580A buttons (displaying and unseen) are qualified by IEEE 323-1974, IEEE 344-1975, IEEE 381-1977and NUREG 0588, Rev. 1 for Functional and/or Pressure Boundary Integrity Services in limited, challenging applications. The button cabinet for the change plug is drawn stainless metal with a locked crystal neck. No additional conduit seals are required to ensure legitimacy of the instrument.