Vented versions of the CD 375 Series of miniature AC-operated LVDT position sensors are available from Macro Sensors (Pennsauken, NJ). The sensors withstand high pressures and temperatures in applications where space is at a premium and the environment is hostile. As the coil assembly of the sensor is vented to equalize pressure inside and outside the LVDT linear position sensor, units can withstand a combination of high pressure and temperatures, shock, and vibration. Since vent holes in the housing expose the coils inside, fluid must be electrically nonconductive and chemically benign.
The sensors operate in temperature extremes of -65 °F to +400 °F (-55 °C to +200 °C), and operating pressures of 35 kpsi. High temperature ratings are achieved using internal materials rated for these temperatures. They are available in full-scale measurement ranges from ±0.025" to ±1.0.