Abstract: The embodiments described herein allow a user device to communicate with one or more components within a TRS via a single point communication scheme. That is, a single point access coordinator of a TRS can be configured to receive a message from a user device via a commercial grade communication link, process the message (e.g., determine which TRS component the message is intended for, determine whether the message is a proper message, unpack the message from a commercial grade communication protocol, repack the message into a rugged industrial grade communication protocol, etc.) and relay that message to one or more components of the TRS via a rugged industrial grade communication link within the TRS.

Abstract: The embodiments described herein allow a user device to communicate with one or more components within a TRS via a single point communication scheme. That is, a single point access coordinator of a TRS can be configured to receive a message from a user device via a commercial grade communication link, process the message (e.g., determine which TRS component the message is intended for, determine whether the message is a proper message, unpack the message from a commercial grade communication protocol, repack the message into a rugged industrial grade communication protocol, etc.) and relay that message to one or more components of the TRS via a rugged industrial grade communication link within the TRS.

Abstract: A method for efficiently maintaining the temperature of fluid in a conditioned space at a predetermined set point temperature, the method comprising the steps of: (a) operating the temperature control system in a first operating mode; (b) sensing the temperature of the conditioned space fluid; (c) calculating the Integral Error of the temperature of the conditioned space fluid; and (d) if the Integral Error equals or exceeds a predetermined Integral Error threshold value for the first operating mode, switching the unit to a second operating mode.

Abstract: A refrigeration unit of the type having an economizer cycle driven by a prime mover cooled by a liquid coolant. Electrical control configures refrigerant flow paths of the unit to provide heating and cooling cycles, as required to control the temperature of a conditioned space to a predetermined set point temperature. Heat from the liquid coolant is used to enhance the heating cycle. A heating cycle is initiated immediately, when required, when the temperature of the liquid coolant is above a predetermined temperature. A heating cycle is delayed by a special refrigeration cycle which increases the load on the prime mover, when the temperature of the liquid coolant is not above the predetermined temperature.

Abstract: Methods and apparatus for monitoring conditions which may cause shut down of a refrigeration unit. When a condition of the refrigeration unit is detected which requires shut down, a shut down counter is incremented and the shut down is made with the provision for automatic restart of the refrigeration unit in response to predetermined parameters of the refrigeration unit. When the predetermined parameters initiate automatic re-start of the refrigeration unit, a timer is started. If the refrigeration unit operates for a predetermined period of time without shut down, the counting means is reset. A shut down before expiration of the predetermined timing period again increments the shut down counter. In one embodiment, when a predetermined condition which may cause shut down approaches a predetermined shut down value, the methods and apparatus modify the operation of the refrigeration unit one or more times in an attempt to prevent shut down.

Abstract: A method of controlling a refrigeration system by determining an average air temperature by sensing and averaging evaporator return and discharge air temperatures, and developing an average error by using the average air temperature and a selected set point temperature. The average air temperature is then used to calculate a proportional error and an integral error, and the discharge air temperature is used to calculate a floor error. The proportional error, integral error and floor error are weighted by predetermined gain factors and then summed to provide an error signal which is used to modulate the capacity of the refrigeration system, with the control mode depending upon the location of the error signal relative to set point.