# US 2018/0320690 A1 · Diagnostic System > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0320690 A1 - Document ID: US20180320690A1 - Status: Published application - Kind: A1 - Application number: 16/036,331 - Filed: 2018-07-16 - Published: 2018-11-08 - Earliest claimed: 2009-05-18 - Assignees: Emerson Climate Technologies, Inc. - Applicants: Emerson Climate Technologies, Inc. - Inventors: Hung M. PHAM; Nagaraj JAYANTH - Web page: https://patentgrep.com/patent/US20180320690A1 ## CPC - F04C 28/28: Safety arrangements; Monitoring - F04B 49/065: {and making use of computers} - F04B 51/00: Testing machines, pumps, or pumping installations - F04C 18/0215: {where only one member is moving} - F04C 23/008: {Hermetic pumps} - F04C 2240/81: Sensor, e.g. electronic sensor for control or monitoring - F04C 2270/07: Electric current - F04C 2270/80: Diagnostics - F04C 2270/86: Detection - F04C: ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS (engines F03C); ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS - F04B: POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS (machines for liquids, or pumps, of rotary-piston or oscillating-piston type F04C; non-positive-displacement pumps F04D; pumping of fluid by direct contact of another fluid or by using inertia of fluid to be pumped F04F) ## Abstract A diagnostic system for a compressor is provided. The compressor includes a compression mechanism and a motor. The diagnostic system includes processing circuitry and memory and may be operable to differentiate between a low-side fault and a high-side fault by monitoring a rate of current rise drawn by the motor for a first predetermined time period following compressor startup. The diagnostic system may be operable to predict a severity level of a compressor condition based on a fault history stored in the memory. ## Claims ### Claim 1 A diagnostic system for a compressor including a compression mechanism and a motor, the diagnostic system comprising processing circuitry and memory and operable to differentiate between a low-side fault and a high-side fault by monitoring a rate of current rise drawn by said motor for a first predetermined time period following compressor startup, said diagnostic system operable to predict a severity level of a compressor condition based on a fault history stored in said memory, said processing circuitry differentiates amongst cycling of a high-pressure cutout switch, cycling of a low-pressure cutout switch, and cycling of a motor protector based on said rate of current rise in combination with an ON time of the compressor and an OFF time of the compressor. ### Claim 2 (depends on 1) The diagnostic system of claim 1, wherein said rate of current rise is determined by calculating a ratio of a running current drawn by said motor during said first predetermined time period over a stored reference current value taken during a second predetermined time period. ### Claim 3 (depends on 2) The diagnostic system of claim 2, wherein said first predetermined time period is approximately three (3) to five (5) minutes. ### Claim 4 (depends on 2) The diagnostic system of claim 2, wherein said second predetermined time period is approximately seven (7) to twenty (20) seconds following said compressor startup. ### Claim 5 (depends on 2) The diagnostic system of claim 2, wherein said processing circuitry declares a high-side fault if said ratio exceeds approximately 1.4 during said first predetermined time period. ### Claim 6 (depends on 2) The diagnostic system of claim 2, wherein said processing circuitry declares a low-side fault if said ratio is less than approximately 1.1 during said first predetermined time period. ### Claim 7 (depends on 1) The diagnostic system of claim 1, wherein said processing circuitry is operable to predict said severity level of said compressor condition based on at least one of a sequence of historical compressor fault events and a combination of the types of said historical compressor fault events. ### Claim 8 (depends on 1) The diagnostic system of claim 1, wherein said rate of current rise is determined by calculating a ratio of a running current drawn by said motor during said first predetermined time period over a stored reference current value taken during a second predetermined time period. ### Claim 9 (depends on 8) The diagnostic system of claim 8, wherein said processing circuitry declares a high-side fault if said ratio exceeds approximately 1.4 during said first predetermined time period and declares a low-side fault if said ratio is less than approximately 1.1 during said first predetermined time period. ### Claim 10 A diagnostic system for a compressor including a compression mechanism and a motor, the diagnostic system comprising processing circuitry and memory and operable to differentiate between a low-side fault and a high-side fault by monitoring a rate of current rise drawn by said motor for a first predetermined time period following compressor startup, wherein said processing circuitry is operable to predict a severity level of a compressor condition based on at least one of a sequence of historical compressor fault events and a combination of the types of said historical compressor fault events. ### Claim 11 (depends on 10) The diagnostic system of claim 10, wherein said rate of current rise is determined by calculating a ratio of a running current drawn by said motor during said first predetermined time period over a stored reference current value taken during a second predetermined time period. ### Claim 12 (depends on 11) The diagnostic system of claim 11, wherein said first predetermined time period is approximately three (3) to five (5) minutes. ### Claim 13 (depends on 11) The diagnostic system of claim 11, wherein said second predetermined time period is approximately seven (7) to twenty (20) seconds following said compressor startup. ### Claim 14 (depends on 11) The diagnostic system of claim 11, wherein said processing circuitry declares a high-side fault if said ratio exceeds approximately 1.4 during said first predetermined time period. ### Claim 15 (depends on 11) The diagnostic system of claim 11, wherein said processing circuitry declares a low-side fault if said ratio is less than approximately 1.1 during said first predetermined time period. ### Claim 16 (depends on 10) The diagnostic system of claim 10, wherein said processing circuitry differentiates amongst cycling of a high-pressure cutout switch, cycling of a low-pressure cutout switch, and cycling of a motor protector based on said rate of current rise in combination with an ON time of the compressor and an OFF time of the compressor. ### Claim 17 (depends on 16) The diagnostic system of claim 16, wherein said rate of current rise is determined by calculating a ratio of a running current drawn by said motor during said first predetermined time period over a stored reference current value taken during a second predetermined time period. ### Claim 18 (depends on 17) The diagnostic system of claim 17, wherein said processing circuitry declares a high-side fault if said ratio exceeds approximately 1.4 during said first predetermined time period and declares a low-side fault if said ratio is less than approximately 1.1 during said first predetermined time period. ### Claim 19 A compressor comprising a shell, a compression mechanism, a motor, and a diagnostic system, said diagnostic system including processing circuitry and memory and operable to differentiate between a low-side fault and a high-side fault by monitoring a rate of current rise drawn by said motor for a first predetermined time period following compressor startup, said diagnostic system operable to predict a severity level of a compressor condition based on a fault history stored in said memory, said processing circuitry differentiates amongst cycling of a high-pressure cutout switch, cycling of a low-pressure cutout switch, and cycling of a motor protector based on said rate of current rise in combination with an ON time of the compressor and an OFF time of the compressor. ### Claim 20 (depends on 19) The compressor of claim 19, wherein said processing circuitry is operable to predict said severity level of said compressor condition based on at least one of a sequence of historical compressor fault events and a combination of the types of said historical compressor fault events.