Complex impedance moisture sensor and sensing method

A container enclosing a cavity configured to enclose objects in a low moisture environment, the container comprising:

• a top portion, a bottom portion, and sides extending between the top portion and the bottom portion thereof, each of the top portion, the bottom portion, and the sides comprising an inner surface and an outer surface;
• and
• a planar moisture sensor mounted to and extending over at least a portion of at least one of the inner surface or the outer surface of at least one of the top portion, the bottom portion, or the sides, the planar moisture sensor comprising:
• a first electrode comprising a flat conductive member having an inner surface and an outer surface;
• a second electrode spaced apart from the first electrode, the second electrode comprising a flat conductive member having an inner surface and an outer surface, and
• a dielectric layer comprising an absorbent dielectric polymer material positioned between and in electrical contact with the inner surfaces of the first electrode and the second electrode.

A method for detecting moisture in insulation surrounding a pipe, the method comprising:

• applying an alternating electrical current to a planar moisture sensor positioned in insulation at least partially covering an outer surface of the pipe, the planar moisture sensor comprising:
• a first electrode comprising a flat conductive member having an inner surface and an outer surface;
• a second electrode spaced apart from the first electrode, the second electrode comprising a flat conductive member having an inner surface and an outer surface, and a dielectric layer comprising an absorbent dielectric polymer material positioned between and in electrical contact with the inner surfaces of the first electrode and the second electrode;
• continually or periodically measuring a complex impedance (ohms) of the dielectric layer with sensor electronics connected to the first and/or the second electrodes;
• and
• determining an amount of moisture within the insulation based on the measured complex impedance (ohms).