Download York YS Technical data
Transcript
035L02381-GB0 2.3 Motor The compressor motor is an open drip-proof, squirrel cage induction type. The motor has a D-flange and cast iron adaptor mounted rigidly to the compressor for accurate alignment of motor and compressor shafts. The motor drive shaft is connected to the compressor shaft with a flexible disc coupling. Coupling has all metal construction with no wearing parts to assure long life, and no lubrication requirements to provide low maintenance. On units supplied without the optional solid state starter, for use with a remote electromechanical starter, a large steel motor terminal box with gasketed front access cover is provided for field connected conduit. Six terminals are provided in the terminal box, two for each motor winding, allowing connection for star-delta (S/D) or direct-on-line (DOL) starting. Jumpers are provided for direct-on-line connection. Motor terminal lugs are not provided. Overload/over-current transformers are fitted as standard. 2.4 Oil Separator The oil separator removes the oil that was injected into the compressor. The separator is a horizontal three stage design without moving parts. Figure 2.3 Oil Seperator 2- 3 In the first stage of oil separation, high velocity oil and refrigerant gas in the compressor discharge line under goes a rapid reduction in velocity as it enters the large diameter oil separator. Most of the oil drops out of the refrigerant gas stream due to the reduction in velocity. The oil falls by gravity into the oil reservoir located in the bottom of the oil separator. The second stage of oil separation is accomplished by directing the refrigerant gas through mesh pads that have an extended surface area. Smaller liquid oil droplets are collected on the extended surface area of the wire mesh pads where the oil falls by gravity into the oil reservoir. The third and final stage of oil separation is achieved in the oil coalescing element section of the oil separator. The oil mixed with the refrigerant entering the coalescer element is a very fine aerosol mist. These small aerosol mist particles wet the coalescer element media and form larger oil droplets which fall by gravity to the bottom of the coalescer element section. The oil collected in the coalescer section is drained from the oil separator with a small amount of refrigerant gas. This provides the high pressure “gas drive” for the eductors to return oil from the evaporator. The oil separator has a design working pressure (DWP) of 20.6 bar. The separator is fitted with a single or dual pressure relief device (depending on safety code requirements) set at 20 bar.