Avoid Low Compression Ratio Conditions; On/Off Cycle; Rotation Direction Of Compressor; Deep Vacuum Operation - Panasonic 4CW056MA01 Applications Manual

Horizontal scroll compressors
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1) Compressor speed ≤30rps , for more than 1 hour continuous operation;
2) 30rps< compressor speed ≤40rps, for more than 4 hours continuous operation;
3) Compressor speed ≥75rps , for more than 40 minutes continuous operation;
This recommendation is to keep the safe oil level inside of compressor and make sure the sufficient lubrication,

3.10 Avoid low compression ratio conditions

Compressor internal oil supply depends on internal oil pump and the rotation speed, do not run the
compressor in the low compression ratio conditions with lower speed (especially 30~39rps).
If the cooling operation is required at lower ambient temperature condition, system should be designed to
decrease the fan speed of condenser, and increase the compressor running speed, to maintain the proper
compression ratio of compressor.

3.11 On/off cycle

The on/off cycle of compressor shall not be more than 6 cycles per hour.
The compressor should be operated continuously at least for 5 minutes after being turned on. Allow a
minimum of 3 minutes shut-off time before restarting. Or restart the compressor after the pressure difference
between high side and low side balances.

3.12 Rotation direction of compressor

Wiring shall be connected in accordance with the wiring diagram mentioned in the compressor specification.
Otherwise the compressor will run into reverse operation and breakdown. Never do this.

3.13 Deep vacuum Operation

Scroll compressors should never be used to evacuate an air-conditioning or refrigeration system. As a high
volumetric efficiency machine, compressor will achieve extremely low vacuums when the suction side is
restricted, this may cause internal arcing at the electric terminal and the damage of compressor.
Figure 3-4


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