A variable frequency drive (VFD) cabinet ventilation system, apparatus and method is described. A VFD cabinet includes an internal air circulating closed circuit that extends through an inside of an air-to-air heat exchanger and an external air open circuit extending around an outside of the heat exchanger. The circulating internal air closed circuit extends through a chamber closed to ingress of external air, the chamber including electrical components of a VFD system. The external air open circuit makes a turn from downwards to upwards before flowing through a VFD chassis including a drive of the VFD system. A VFD cabinet ventilation method includes turning a flow of cabinet ventilation air from downwards to upwards to separate dirt from the ventilation air, passing the separated ventilation air through a VFD chassis, and circulating internal cabinet air through a closed circuit including an inside of a heat exchanger.

An embodiment includes a cooling unit, including: a housing configured to attach to an enclosure opening in a sealed manner, where the enclosure houses heat generating electrical equipment; the housing including: a first ambient side area including a compressor, condensing coils, and an ambient air intake and outlet; a first enclosure side area situated above the first ambient side area and including an electrical box that includes one or more relays and a digital controller; a second enclosure side area extending along the rear side of the housing and communicating with the first enclosure side area, including an impeller, an enclosure air intake, an enclosure air return, and evaporator coils in fluid communication with the condenser coils; and a second ambient side area including an impeller and one or more hot air exhausts; where all components of the cooling unit are non-sparking and non-arcing; and where the first and second ambient side areas are sealed off from the first and second enclosure side areas. Other embodiments are described and claimed.

Heat exchanger assemblies and methods are provided for cooling the interior of an enclosure (e.g., electrical cabinets, computer server racks, chemical chambers, and animal cages). Heat is transferred via thermal conduction from a first plurality of surfaces positioned inside the enclosure to a second plurality of surfaces positioned outside the enclosure. The first and second plurality of surfaces remain in thermal contact with one another during use. Heat is dissipated from the second plurality of surfaces to the ambient air outside the isolated environment without the ambient outside air mixing together with the air inside the enclosure. This, in turn, inexpensively removes heat from the air inside the enclosure and prevents contaminants from entering the enclosure.

An inverter power cabinet includes a cabinet body and power devices arranged in the cabinet body. The cabinet body includes a low-protection grade installation cavity and an airtight high-protection grade installation cavity hermetically isolated from each other; the power devices include high protection grade power devices arranged in the low-protection grade installation cavity and low-protection grade power devices arranged in the high-protection grade installation cavity; the low-protection grade installation cavity has an outer cold air inlet and an inner hot air outlet in communication with outside world, and a first fan is provided in the low-protection grade installation cavity; and the inverter power cabinet includes a heat exchanger configured to dissipate heat of the high-protection grade installation cavity. The inverter power cabinet can avoid direct contact of the low-protection grade power devices with a harsh environment, thereby preventing the contaminated cold air from damaging the low-protection grade power devices.

In order to reduce the dimensions of a heat exchanger it is suggested to configure the heat exchanger in such a way that it has a heat exchanging element comprising a condenser unit and an evaporator unit. The evaporator unit comprises a lower end area, an upper end area and a plurality of channels for transporting a refrigerant from the lower end area to the upper end area, said refrigerant comprising liquid and gas. The upper end area is connected to the lower end area by a first line which is configured to transfer only liquid from the upper end area to the lower end area.

In order to reduce the dimensions and costs of a heat exchanger, while at the same time increasing its heat effectiveness, it is suggested to configure the heat exchanger such that a condenser side and an evaporator side of the heat exchanger are separated from each other by a barrier.

An electrical cabinet for receiving functional electrical units, each including a plurality of electrical devices arranged on a bracket; and a mechanism for attaching the functional electrical units, the attaching mechanism configured to receive the functional electric units along a separation plane defining a first space located toward a front portion, and a second space located toward a back portion; a partition dividing the second space into a first subspace located toward the front portion and a second subspace located toward the rear portion, the partition configured in the electrical cabinet to form at least two passages enabling an airflow to circulate between the first subspace and the second subspace; and a cooling source arranged to be in contact with the airflow.

A variable frequency drive (VFD) cabinet ventilation system, apparatus and method is described. A VFD cabinet includes an internal air circulating closed circuit that extends through an inside of an air-to-air heat exchanger and an external air open circuit extending around an outside of the heat exchanger. The circulating internal air closed circuit extends through a chamber closed to ingress of external air, the chamber including electrical components of a VFD system. The external air open circuit makes a turn from downwards to upwards before flowing through a VFD chassis including a drive of the VFD system. A VFD cabinet ventilation method includes turning a flow of cabinet ventilation air from downwards to upwards to separate dirt from the ventilation air, passing the separated ventilation air through a VFD chassis, and circulating internal cabinet air through a closed circuit including an inside of a heat exchanger.

A shelf thermostat device and a thermostat system. The shelf thermostat device includes a fixing bracket and a heat exchanger. An electronic device is detachably disposed at the fixing bracket. The heat exchanger is detachably disposed at the fixing bracket and layer arranged in a row with the electronic device. The heat exchanger has a heat exchanging core. The heat exchanging core has a first side and a second side opposite to the first side, and a plurality of internal channels and a plurality of external channels. The internal channels and the external channels are disposed staggered and isolated with each other. An internal air flows between the internal channels and the electronic device. An external air flows to the second side of the heat exchanging core from the first side of the heat exchanging core through the external channels.

A computer room air conditioner (CRAC) unit includes a housing having an inlet configured to receive IT air and an outlet configured to exhaust treated air. The CRAC unit further includes a heat exchanger supported by the housing and disposed between the inlet and the outlet of the housing and at least one fan module supported by the housing. The at least one fan module is configured to draw IT air into the housing through the inlet, direct IT air through the heat exchanger, and exhaust treated air through the outlet. The CRAC unit further includes an airfoil frame secured to the housing at the inlet of the housing.