Switch assembly and system for high-level monitoring
A level monitoring system for a floating roof tank is provided. The level monitoring system includes a switch electrically connected to a monitor. When the tank reaches a high fill level, the switch closes an electrical circuit. The monitor senses that the circuit has become closed, indicating the high fill level, and sends a signal to an alarm module. The level monitoring system may use either a cable pull switch or a tilt switch that are activated by the floating roof of the tank when the a predetermined level has been reached.
1 . A level monitoring system for a tank having a floating roof. the level monitoring system comprising:
a switch having a biasing means for applying a first force on the switch to bias the switch to a first state;
a counter load operatively coupled to and adapted to be suspended from the switch, the counter load acting on the switch with a second force opposite the first force to bias the switch to a second state;
a monitor electrically connected to the switch; and
wherein the second force is greater than the first force when the floating roof is below a predetermined level, and wherein the first force is greater than the second force when the floating roof is at least equal to the predetermined level.
2 . The level monitoring system of claim 1 , further comprising an alarm module in communication with the monitor.
3 . The level monitoring system of claim 2 , wherein the monitor wirelessly communicates with the alarm module.
4 . The level monitoring system of claim 1 , wherein the monitor is battery powered.
5 . The level monitoring system of claim 4 , wherein switch includes gold electrical contacts.
6 . The level monitoring system of claim 1 , wherein the counter load is a weight that is hangs freely over the floating roof.
7 . The level monitoring system of claim 6 , wherein the weight comprises brass.
8 . The level monitoring system of claim 1 , wherein the first state of the switch is open and wherein the second state of the switch is closed.
9 . A level monitoring system for a tank having a floating roof the level monitoring system comprising:
a monitor;
a tilt switch assembly operatively coupled to and adapted to be suspended from the monitor, the tilt switch having a housing that defines a pivot point at one end thereof and a switch positioned within the housing; and
wherein the tilt switch assembly is in a first state when the floating roof is below a predetermined level, and wherein the wherein the tilt switch is in a second state when the floating roof is at least equal to the predetermined level.
10 . The level monitoring system of claim 9 , wherein the monitor communicates with an alarm module.
11 . The level monitoring system of claim 10 , wherein the alarm module is remotely located from the monitor, and wherein the monitor wirelessly communicates with the alarm module.
12 . The level monitoring system of claim 9 , wherein the monitor is battery operated.
13 . The level monitoring system of claim 12 , wherein the tilt switch includes a pair of electrical contacts comprising gold.
14 . The level monitoring system of claim 9 , wherein the tilt switch is a ball bearing tilt switch.
15 . The level monitoring system of claim 1 , wherein the housing of the tilt switch assembly comprises a non-sparking material.
16 . The level monitoring system of claim 15 , wherein the housing is filled with an inert gas.
17 . A level monitoring system for a tank having a floating roof, the level monitoring system comprising:
a monitor;
a body;
suspension means coupled to the body for suspending the body above the floating roof;
wherein the body is movable between a first position where it is fully supported by the suspension means and a second position where it is not fully supported by the suspension means; and
a switch electrically connected to the monitor, the switch being in a first state when the body is in the first position and in a second state when the body is in the second position.
18 . The level monitoring system of claim 17 , wherein the switch is integral with the hanging body.
19 . The level monitoring system of claim 18 , wherein the switch is a tilt switch.
20 . The level monitoring system of claim 17 , wherein the body hangs from the switch by the suspension means, the switch further including biasing means for biasing the switch in a direction opposite the suspension means.