Canadian Patents Database

Claims page

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Patent Document Number: 2067002

(54) English Title: MULTIPLE CIRCUIT OVERLOAD PROTECTION DEVICE

(54) French Title: DISPOSITIF DE PROTECTION CONTRE LES SURCHARGES DE CIRCUITS MULTIPLES

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Claims:

Note: Claims are shown in the official language in which they were submitted.




WHAT IS CLAIMED IS


1- An apparatus for prevention of overloading of a two-wire
circuit of a three wire electrical system comprising in
combination:

a first voltage supply line and a second voltage supply
line;

a first load and a second load, wherein said first load is
connected to said first voltage supply line;

means for sensing when said first and second supply lines
are out of phase;

means responsive to said means for sensing for connecting
said second load to said second voltage supply line when said
first and second supply lines are out of phase; and

a bypass switch means for bypassing said means for
connecting said second load to a second voltage supply line,
regardless of whether said first and second supply lines are in
or out of phase.

2- The apparatus in accordance with claim 1, further comprising
means for indicating when said switch means for by passing is
open or closed when said first and second voltage supply lines
are out of phase.



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3- The apparatus in accordance with claim 1, further comprising
means responsive to said means for sensing for supplying a
voltage to an indicator when said first and second voltage
supply lines are out of phase.

4- The apparatus in accordance with claim 1, further comprising
an indicator lamp for signaling the presence of out of phase
power on said first and second voltage supply lines.

5- The apparatus in accordance with claim 1, further
comprising a first exclusive OR gate for comparing the phase of
voltages on said first and second voltage supply lines, and
providing an output if said voltages are out of phase.

6- The apparatus in accordance with claim 5, further
comprising a switch means responsive to said first exclusive OR
gate for turning on and off a load connected to one of said
first and second voltage supply lines.

7- The apparatus in accordance with claim 5, further
comprising a second exclusive OR gate for detecting the presence
of a voltage on one of said first and second voltage supply
lines,



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means responsive to said second exclusive OR gate and to said
first exclusive OR gate for providing an indication that a
voltage is present on said second voltage supply line, and that
the voltages on said first and second voltage supply lines are
out of phase.

8- An apparatus connecting a second load to a second circuit
when said second circuit is out of phase with a first circuit
having a first load comprising in combination:

means for sensing the phase of said first and second
circuits;

means for automatically connecting said second load to said
second circuit when said first and second circuits are out of
phase; and

means for bypassing said means for sensing and for
connecting said second load when said first and second circuits
are in phase or out of phase.

9-The apparatus in accordance with claim 8, further comprising
means responsive to said means for sensing for comparing the
phases of said first and second circuits, and means for
producing a signal when said first and second means are out of
phase.



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10-The apparatus in accordance with claim 8, further comprising
means for indicating when said first and second circuits are out
of phase.

11-The apparatus in accordance with claim 8, further comprising
means for indicating when said first load and said second load
are respectively connected to said first and second circuits
having different phases.

12- The apparatus in accordance with claim 8, further comprising
means for indicating when said first and second circuits are out
of phase and when said load is connected to said second circuit.

13- The apparatus in accordance with claim 8, further comprising
manual switch means for preventing automatically connecting said
second load to said second circuit when said first and second
circuits are out of phase.



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