Hanbell RC2-D, Technical Manual

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RC2-D Technical Manual
cylinder bypasses to the suction side, causing the piston and slide valve to move to the left
and part of the refrigerant gas bypasses the suction port from the compression chamber. At
this time, due to the reduction of refrigerant discharge, resulting in the reduction of
refrigeration capacity. The piston spring is used to push the piston back to its starting position.
If the compressor is started under full load, it will generate over-current start-up. Therefore, in
order to reduce the start-up current of the next start-up, the slide valve should be unloaded to
the minimum load position during shutdown
.
3.2.1 3 or 4 Step Capacity control system
The compressor is equipped with two solenoid valves (RC2-100, RC2-140 and RC2-180) or three
solenoid valves (other models). They can control the capacity of the compressor from the
minimum capacity to the full load state (100%). These two / three normally closed (NC)
solenoid valves are used to control the required capacity.When the compressor with a 3 / 4
step capacity control system, the compressor is loaded through 33% - 66% to 100% or 25% -
50% - 75% to 100% process, and the
compressor is unloaded through 100% -
66% - 33% or 100% - 75% - 50% to 25%
process. If needs to operate under 25%
loading for long time, oil return, motor
cooling and high discharge temperature
should be considered. For example, the
motor is cooled by liquid injection and
the lubricating oil is cooled by external
oil circuit
。
Figure 3-3 (3&4 step) Capacity control
No. Part Name No. Part Name
1 Suction filter 10 Lubricanting oil
2 Suction gas 11 Oil separator filter
3 Motor 12 Discharge gas
4 Oil filter 13 Capillary
5 Suction bearing 14 Solenoid valve
（
25%/33%
）
6 Male rotor 15 Solenoid valve
（
50%/66%
）
7 Discharge bearing 16 Solenoid valve
（
75%
）
8 Muffler tube 17 Sliding valve
9 Discharge gas *
RC2 -100
～
180 only with
33%/66%
25%/33%
75%
50%/66%