Sensing moisture or corrosion
An elongate sensor, system and method for detecting moisture and/or corrosion. The elongate sensor can include multiple conductors located alongside one another, or parallel with each other, not contacting each other and not making direct electrical contact between one another. Each conductor has a distinct pattern of alternating insulated and non-insulated portions. In each insulated portion, the Nth conductor is within an electrically non-conducting material forming Nth non-detecting portions. In each non-insulated portion, the Nth conductor is exposed or not electrically insulated forming Nth detecting portions. Each of the Nth detecting or non-detecting portions would have a single Nth unit length. Each Nth unit length is a distance equal to two to the power of N minus one first unit lengths, 2 (N−1) times the first unit length. Electrically conductive object provides a base conductor and/or the elongate sensor includes a base conductor.
1 . An elongate sensor for a system for detecting moisture and/or corrosion, the elongate sensor including at least a first conductor, a second conductor and a third conductor, each of the at least first, second and third conductors being located in parallel to each other by an electrically non-conductive carrier material to prevent the conductors from coming into direct electrical conductive contact with each other or external conductive surfaces, while permitting ingress of conductive media;
the first conductor being exposed or electrically non-insulated for a first unit length forming an initial first detecting portion, then alternately being electrically insulated for a distance equal to the first unit length forming first non-detecting portions or being electrically non-insulated for a distance equal to the first unit length forming additional first detecting portions of the first conductor;
the second conductor being electrically insulated for a distance equal to a second unit length minus the first unit length forming an initial second non-detecting portion, then alternately being electrically non-insulated for a distance equal to the second unit length forming second detecting portions or being electrically insulated for a distance equal to the second unit length forming additional second non-detecting portions of the second conductor, the second unit length being double the first unit length;
the third conductor being electrically insulated for a distance equal to a third unit length minus the first unit length forming an initial third non-detecting portion, then alternately being electrically non-insulated for a distance equal to the third unit length forming third detecting portions or being electrically insulated for a distance equal to the third unit length forming non-detecting portions of the third conductor, the third unit length being double the second unit length.
2 . The elongate sensor according to claim 1 , wherein the at least a first conductor, a second conductor and a third conductor further includes a base conductor,
the base conductor being exposed or non-insulated and being located parallel to the first, second and third conductors by the non-conductive material.
3 . The elongate sensor according to claim 2 , further including at least one additional base conductor, wherein the additional base conductor or each additional base conductor is corrodible.
4 . The elongate sensor according to claim 1 , wherein at least one of the at least a first conductor, a second conductor and a third conductor further includes a resistor in series with the respective conductor.
5 . The elongate sensor according to claim 1 , wherein at least one of the at least a first conductor, a second conductor and a third conductor further includes at least two resistors in series with the respective conductor, equispaced along the respective conductor.
6 . The elongate sensor according to claim 1 , wherein the first unit length is up to and including 4 metres.
7 . The elongate sensor according to claim 1 , wherein the elongate sensor is held, adhered or fixed under a substantially horizontal object and/or spiraled around a substantially vertical object.
8 . The elongate sensor as claimed in claim 1 , including a fourth conductor;
the fourth conductor being electrically insulated for a distance equal to a fourth unit length minus the first unit length forming an initial fourth non-detecting portion, then alternately being electrically non-insulated for a distance equal to the fourth unit length forming fourth detecting portions or being electrically insulated for a distance equal to the fourth unit length forming fourth non-detecting portions of the fourth conductor, the fourth unit length being double the third unit length.
9 . The elongate sensor as claimed in claim 8 , including an Nth conductor;
the Nth conductor being electrically insulated for a distance equal to an Nth unit length minus the first unit length forming an initial Nth non-detecting portion, then alternately being electrically non-insulated for a distance equal to the Nth unit length forming Nth detecting portions or being electrically insulated for a distance equal to the Nth unit length forming Nth non-detecting portions of the Nth conductor, the Nth unit length being 2 (N−1) times the first unit length.
10 . The elongate sensor according to claim 1 , wherein the non-conductive carrier material and the conductors are woven together.
11 . The elongate sensor according to claim 1 , wherein the non-conductive carrier material is a strip or tape to which the conductors are fastened or printed.
12 . The elongate sensor according to claim 1 , including a detector unit connected electrically to each conductor.
13 . A system for detecting moisture and/or corrosion of an object, the system including at least one elongate sensor and a monitoring unit:
the elongate sensor including at least a first conductor, a second conductor and a third conductor, each of the at least first, second and third conductors being located in parallel to each other by an electrically non-conductive carrier material to prevent the conductors from coming into direct electrical conductive contact with each other or external conductive surfaces, while permitting ingress of conductive media;
the first conductor being exposed or electrically non-insulated for a first unit length forming an initial first detecting portion, then alternately being electrically insulated for a distance equal to the first unit length forming first non-detecting portions or being electrically non-insulated for a distance equal to the first unit length forming additional first detecting portions of the first conductor;
the second conductor being electrically insulated for a distance equal to a second unit length minus the first unit length forming an initial second non-detecting portion, then alternately being electrically non-insulated for a distance equal to the second unit length forming second detecting portions or being electrically insulated for a distance equal to the second unit length forming non-detecting portions of the second conductor, the second unit length being double the first unit length;
the third conductor being electrically insulated for a distance equal to a third unit length minus the first unit length forming an initial third non-detecting portion, then alternately being electrically non-insulated for a distance equal to the third unit length forming third detecting portions or being electrically insulated for a distance equal to the third unit length forming non-detecting portions of the third conductor, the third unit length being double the second unit length;
the monitoring unit being connected to each of the at least first, second and third conductors individually and being configured to detect electrical conductivity between any pair of the at least first, second and third conductors.
14 . The system as claimed in claim 13 , further including a base conductor wherein the monitoring unit is configured to detect electrical conductivity between any pair of the conductors, including the base conductor and the at least first, second and third conductors.
15 . The system as claimed in claim 14 , wherein the base conductor is included in the elongate sensor, is non-insulated and is located parallel to the at least first, second and third conductors by the non-conductive carrier material, to prevent direct electrical contact with the conductors or any external surfaces and to permit ingress of conductive media.
16 . The system as claimed in claim 14 , wherein the elongate sensor is spiraled around or held adjacent or against an underside of an object,
the object being conductive and forming the base conductor.
17 . The system as claimed in claim 14 , wherein the monitoring unit converts detected electrical conductivity between the base conductor and the at least first, second and third conductors into a decimal number of first unit lengths or into a distance.
18 . The system as claimed in claim 14 , wherein the monitoring unit detects electrical resistance, impedance and/or capacitance between individual pairs of the conductors, and determines a location of at least one position or region of corrosion or moisture.
19 . The system as claimed in claim 18 , wherein the monitoring unit is connected to a first end and a second end of each of the conductors and detects and compares electrical resistance, impedance and/or capacitance measured from the first end to electrical resistance, impedance and/or capacitance measured at the second end.
20 . The system as claimed in claim 13 , wherein the monitoring unit is directly connected to the conductors of the elongate sensor.
21 . The system as claimed in claim 13 , wherein the monitoring unit is indirectly connected to the conductors of the elongate sensor,
the elongate sensor including a detector unit, the monitoring unit being connected to the detector unit of the elongate sensor.
22 . The system as claimed in claim 13 , wherein monitoring unit obtains a reading from the elongate sensor at a predetermined interval of time.
23 . The system as claimed in claim 13 wherein the monitoring unit converts detected electrical conductivity between the pairs of conductors, into a decimal number of first unit lengths or into a distance.
24 . The system as claimed in claim 13 , further including a base conductor, the base conductor being an additional conductor in the elongate sensor or being the object, wherein the monitoring unit is configured to measure an electrical resistance, impedance and/or capacitance between individual pairs of the conductors, including the base conductor and the first, second and third conductors.
25 . The system as claimed in claim 24 wherein the monitoring unit converts electrical resistance, impedance and/or capacitance between the pairs of the at least first, second and third conductors to determine a location of at least one region of corrosion or moisture.
26 . The system as claimed in claim 25 , wherein the monitoring unit is connected to a first end and a second end of each of the conductors and detects and compares electrical resistance, impedance and/or capacitance measured from the first end to electrical resistance, impedance and/or capacitance measured at the second end.
27 . The system as claimed in claim 13 wherein the sensor monitoring unit periodically measures conductivity and/or resistance, impedance and/or capacitance in the at least one elongate sensor,
the sensor monitoring unit logging or tracking the time periods that a detecting portion is detecting moisture.
28 . The system as claimed in claim 13 wherein the at least one elongate sensor includes multiple elongate sensors on multiple monitored objects,
measured conductivity and/or resistance, impedance and/or capacitance from each sensor being transmitted to the monitoring unit.
29 . The system as claimed in claim 13 wherein the at least one elongate sensor is placed underneath a covering on the object.
30 . A method of detecting moisture or corrosion on an object, the method comprising:
providing an elongate sensor including at least first, second, third, fourth and fifth conductors, each conductor having alternating exposed or electrically non-insulated detecting and electrically insulated non-detecting portions, the length of each detecting and each non-detecting portion of the first conductor having a unit length, each Nth conductor having detecting portion lengths and non-detecting portion lengths of 2 (N−1) times the unit length, the conductors being located in parallel to each other by an electrically non-conductive carrier material or tape, the conductors being prevented from coming into direct electrical contact with each other or the object, while permitting ingress of conductive media.
31 . The method according to claim 30 , wherein providing an elongate sensor includes providing at least one base conductor, the or each base conductor being uninsulated, but being located in parallel to each other and prevented from coming into direct electrical contact with each other while permitting ingress of conductive media.
32 . The method according to claim 30 , wherein providing an elongate sensor includes providing at least one external connector,
the method further including connecting the external connector to the object or to ground, the external connector forming a portion of an external base conductor which forms part of the or a base conductor.
33 . The method according to claim 31 , including installing the elongate sensor adjacent the object.
34 . The method according to claim 33 , including monitoring for connectivity between the base conductor and at least the first, second, third, fourth and fifth conductors.
35 . The method according to claim 34 , including determining a presence of moisture or corrosion on the object:
if no moisture or corrosion is detected on the object, then after a pause of a predetermined time period, the monitoring for connectivity is repeated;
if moisture or corrosion is detected on the object, then calculating and reporting the position of said moisture or corrosion on the object.
36 . The method according to claim 34 , including determining a presence of moisture or corrosion on the object:
if no moisture or corrosion is detected on the object, then after a pause of a predetermined time period, the monitoring for connectivity is repeated;
if moisture or corrosion is detected on the object, then measuring a resistance, capacitance and/or impedance for any or each connection between the base conductor and the at least the first, second, third, fourth and fifth conductors calculating and reporting at least one position of said moisture or corrosion on the object.
37 . The method according to claim 33 , including measuring a resistance, capacitance and/or impedance between at least the first, second, third, fourth and fifth conductors;
determining a presence of moisture or corrosion on the object:
if no moisture or corrosion is detected on the object, then after a pause of a predetermined time period, the measuring a resistance, capacitance and/or impedance is repeated;
if moisture or corrosion is detected on the object, then calculating and reporting at least one position of said moisture or corrosion on the object.