Methods and apparatus for converting a manually operable refrigeration unit to remote operation
US5499512A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 14, 1995 |
| Grant date | Mar 19, 1996 |
| Priority date | — |
| Expiry date | Apr 14, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05D23/1905
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
Methods and apparatus for converting a refrigeration unit having a manually controlled thermostat to remote operation via a data logger, without replacing the manually controlled thermostat. A set point temperature selector associated with the thermostat is fixed at a predetermined value, and a resistance temperature detector (RTD), which is normally connected to a temperature input of the thermostat, is disconnected. A set point temperature for a space conditioned by the refrigeration unit is selected via the data logger. The data logger monitors the temperature of the conditioned space, compares the temperature of the conditioned space with the set point temperature selected via the data logger, and determines an operating mode for the refrigeration unit which will cause the temperature of the conditioned space to be maintained in a predetermined range relative to the set point temperature selected via the data logger. A potentiometer is connected between the data logger and the temperature input of the thermostat. The data logger adjusts the resistance of the potentiometer to correspond to a temperature of the RTD, which, relative to the predetermined set point temperature fixed…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.