Alarm and status monitoring system

• US 3,958,240 A
• Filed: 03/06/1973
• Issued: 05/18/1976
• Est. Priority Date: 03/06/1973
• Status: Expired due to Term

• Current Assignee: Robertshaw Controls Company (Schneider Electric SE)
• Original Assignee: Robertshaw Controls Company (Schneider Electric SE)
• Inventors: Richardson, Edward M. III
• Primary Examiner(s): Habecker, Thomas B.
• Application Number:
  US05/338,493
• Time in Patent Office: 1,169 Days
• Field of Search: 340/213.1, 340/213, 340/412, 340/413, 340/414, 340/415, 340/163, 200/42 R, 200/44
• US Class Current: 340/502
• CPC Class Codes: G08B 23/00 Alarms responsive to unspecified undesired or abnormal conditions

Abstract

Sequentially generated pulses are applied to respective groups of alarm and status condition responsive contacts. A memory is indexed in accordance with the pulses to store individual condition signals received from respective contacts in each group and activate alarm or status indicators. A lock switch operates facilites for partially disabling a manual acknowledge switch which turns off audible and blinking alarm indicators. A printer records the time and a character indicating the specific alarm contact which was activated. Alarm summary command or alarm status summary command switches may be selectively operated to produce a print out of all alarm conditions or a print out of all alarm conditions and the status of all status contacts. The system employs modular units which may be selectively connected in the system to provide lamp annunciator functions and/or printing functions for selective sized groups of contacts.

Claims

1. A condition monitoring system comprising

a plurality of condition means, each for operating in response to a condition, having at least first and second groups of condition means;

sequencing means for sequentially generating a set signal, a first signal and a second signal;

first sensing means responsive to the first signal for sensing the operation of any condition means in the first group of condition means;

second sensing means responsive to the second signal for sensing the operation of any condition means in the second group of condition means;

indicating means responsive to any of the first and second sensing means sensing a condition for indicating the presence of the condition;

manual switch; and

operation changing means responsive to a coincidence of the operation of the switch and a set signal for changing the operation of the indicating means.

2. A condition monitoring system comprising

a plurality of contacts for indicating a condition when operated;

a first line connected to first terminals of a first group of the pluarlity of contacts;

a second line connected to first terminals of a second group of the plurality of contacts;

a third line connected to second terminals of first contacts, one first contact being in each of the first and second groups of contacts;

a fourth line connected to second terminals of second contacts, one second contact being in each of the first and second groups of contacts;

means for sequentially applying first and signals lines;

to the respective first and second lines;

a plurality of memory means, each for changing from a first to a second state to indicate a condition, a respective one of the plurality of memory means corresponding to each of the plurality of contacts;

means for sequentially enabling respective first and second groups of the plurality of memory means in response to the first and second signals;

means for connecting the third line to inputs on first memory means of both first and second groups of the plurality of memory means to change respective enabled first memory means from the first state to the second state in response to a signal on the third line;

means for connecting the fourth line to inputs on second memory means of both first and second groups of the plurality of memory means to change respective enabled second memory means from the first state to the second state in response to a signal on the fourth line, and

indicating means responsive to one of the plurality of memory means changing from a first state to a second state for indicating the presence of a condition.

3. A status condition and alarm condition monitoring system comprising

a plurality of normally open contacts including (a) status contacts for indicating a status condition when closed and (b) alarm contacts for indicating an alarm condition when closed;

a first line connected to first terminals of a first group of the plurality of contacts;

a second line connected to first terminals of a second group of the plurality of contacts;

a third line connected to second terminals of first contacts, one first contact being in each of the first and second groups of contacts;

a fourth line connected to second terminals of second contacts, one second contact being in each of the first and second groups of contacts;

sequencing means for sequentially applying first and second electrical signals to the respective first and second lines;

a plurality of first latch circuits, each corresponding to a respective one of the plurality of contacts, a first group of the first latch circuits having input enabling means connected to the sequencing means for enabling the first latch circuits of the first group of first latch circuits during the first signal, a second group of the first latch circuits having input enabling means connected to the sequencing means for enabling each of the first latch circuits of the second group of first latch circuits during the second signal;

first connecting means for connecting an input of one first latch circuit of each of the first and second groups of latch circuits to the third line to change the one first latch circuits from first to second states when enabled and the respective first contacts are closed;

second connecting means for connecting an input of another first latch circuit of each of the first and second groups of first latch circuits to the fourth line to change the another first latch circuits from first to second states when enabled and the respective second contacts are closed;

a plurality of second latch circuits, each having an input connected to a corresponding one of the plurality of first latch circuits;

an alarm indicator;

first bistable means having first and second states for operating the alarm indicator when the first bistable means is in the second state;

first programmable means connected to the first latch circuits for changing the first bistable means to the second state when any of the first latch circuits corresponding to the alarm contacts change from the first state to the second state;

a manual switch for acknowledging the alarm condition;

third connecting means for connecting the manual switch to enabling inputs of the second latch circuits to change the second latch circuits which correspond to first latch circuits in the second state from first states to second states; and

fourth connecting means connecting the manual switch to the first bistable means for changing the first bistable means from the second state to the first state to terminate operation of the alarm indicator.