Abstract: A terminal assembly configured to conduct current from an external power source to a hermetical motor-compressor unit. The terminal assembly includes a terminal board, at least one opening defined through the thickness of the terminal board, at least a conductive pin received in the opening, and an insulator having a convoluted contour. The insulator may be disposed over the conductive pin and spaced away from the terminal board.

Abstract: A terminal assembly configured to conduct current from an external power source to a hermetical motor-compressor unit. The terminal assembly includes a terminal board, at least one opening defined through the thickness of the terminal board, at least a conductive pin received in the opening, and an insulator having a convoluted contour. The insulator may be disposed over the conductive pin and spaced away from the terminal board.

Abstract: To protect the bearings, lubricant and seals of a refrigerant compressor, the compressor includes one or more inductors for mitigating a high frequency common mode current that produces a high frequency shaft voltage. Each inductor is a ring of magnetic material encircling three insulated cables that convey three-phase power from an adjustable frequency drive to the compressor's motor. Without the inductors, the high frequency shaft voltage can become damagingly high due to the length of a cast iron housing that can be particularly long if the housing contains both a motor and several centrifugal impellers. The high frequency shaft voltage is just one component of a composite adverse shaft voltage. Another component, known as an operationally induced shaft voltage, can be reduced by a grounding contact, so instead of using just an inductor or just a contact, both can be used to provide a total solution to the problem.

Abstract: To protect the bearings, lubricant and seals of a refrigerant compressor, the compressor includes one or more inductors for mitigating a high frequency common mode current that produces a high frequency shaft voltage. Each inductor is a ring of magnetic material encircling three insulated cables that convey three-phase power from an adjustable frequency drive to the compressor's motor. Without the inductors, the high frequency shaft voltage can become damagingly high due to the length of a cast iron housing that can be particularly long if the housing contains both a motor and several centrifugal impellers. The high frequency shaft voltage is just one component of a composite adverse shaft voltage. Another component, known as an operationally induced shaft voltage, can be reduced by a grounding contact, so instead of using just an inductor or just a contact, both can be used to provide a total solution to the problem.

Abstract: To protect the bearings, lubricant and seals of a refrigerant compressor, the compressor includes one or more inductors for mitigating a high frequency common mode current that produces a high frequency shaft voltage. Each inductor is a ring of magnetic material encircling three insulated cables that convey three-phase power from an adjustable frequency drive to the compressor's motor. Without the inductors, the high frequency shaft voltage can become damagingly high due to the length of a cast iron housing that can be particularly long if the housing contains both a motor and several centrifugal impellers. The high frequency shaft voltage is just one component of a composite adverse shaft voltage. Another component, known as an operationally induced shaft voltage, can be reduced by a grounding contact, so instead of using just an inductor or just a contact, both can be used to provide a total solution to the problem.

Abstract: A centrifugal chiller includes both a unit-mounted full-voltage starter and a unit-mounted reduced-voltage starter. The chiller is rather large with a rated cooling capacity of at least 300 tons and is driven by a motor that is powered by at least 2,000 volts. The chiller includes an evaporator shell and a condenser shell in a staggered arrangement to provide a combined height of between 6 and 12 feet and a combined width of between 5 and 8.5 feet. The staggered arrangement of the shells plus mounting the two starters at opposite sides of the motor provide a chiller whose outer dimensions permit the chiller to be shipped as a single package without exceeding certain shipping limits.

Abstract: A tube and shell evaporator operable at near freezing includes a temperature sensor that senses the temperature of chilled water discharging from one or just a few of the very coldest tubes, whereby the sensed temperature is less than the average leaving chiller water temperature (LCWT). The result provides an exceptionally low LCWT, which can be especially desirable in district cooling systems where the chilled water is usually piped a great distance.