Do you need to reduce production and switch off your air compressors temporarily? See below for some guidelines on stopping and re-starting your air compressor.
How to Stop for Periods of Time Due to Factory Closure or Shutdown
If the machines are to be stopped for a prolonged period of time the following rules should be applied:
- General recommendation: If production is stopped completely, manually stop the compressor, even if they are integrated in a central controller. If this is not done, it is possible that the machine will run at minimal capacity to compensate for small leaks in your compressed air network. This could be harmful to your compressed air system.
- VSD compressors: Carry out a program stop, make sure the electrical power supply is left turned on to keep the capacitor bank charged and ready for restart.
- Water-cooled air compressors: After stopping be sure to isolate the water supply. This will stop condensate forming inside the compressor element(s). Don't forget to turn it back on at start up> Please make sure any air blast cooling systems are turned off.
- Atlas Copco Z compressors: These need the main drive shaft to be manually rotated via the motor drive coupling, three complete rotations, once a week. If the Z Compressor is a VSD version, don't forget to turn the power supply back on after turning the compressor over by hand, to protect the inverter drive capacitors.
- Centrifugal / ZH compressors: Should be programmed stopped; leave the power supply on. They need to have the auxiliary oil pump turned on once a week for 10 minutes whilst the compressor is stopped.
- Dryers and gas generators: Can be stopped manually and depressurised if required. For gas generators, when depressurising you should monitor the oxygen level in the machine room.
Starting Up After Long Periods of Shutdown
Inspect your compressor equipment before turning it back on.
First turn off the power supply to the air compressor, remove the drive shaft protection guard and turn the drive coupling to check that the compressor is free to turn. If the compressor turns freely, re fit the guard and turn on the power supply to the compressor; turn on the cooling water if the compressor is water cooled.
Slowly open the compressor air discharge valve until the air pressure equalises between the compressor and the air net. Start the compressor. The air compressor is now back online. If the air compressor is connected to a sequence controller, make sure the compressors are integrated onto the controller/Optimizer.
For adsorption dryers and gas generators never start up against an empty air-net. When starting close the outlet valve behind the dryer or generator and pressurise the system. Then slowly open the outlet valve to pressurise the air-net, this to avoid high air speeds damaging the adsorption material.
Click the button below to get in touch with your local Atlas Copco customer centre or give us a call on 1800 023 469. We will assist you in taking care of your equipment to keep your compressor room in optimal health.
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