Compressor Protective Devices - mycom i125S Instruction Manual

1.4.3

Compressor Protective Devices

 Be sure to adjust the set values and check operation of the protective devices before
the commissioning.
Install necessary protection devices shown in section 2.3.3 "Alarm Set Values" in this manual chapter 2.
Also, install the following protection devices that are not indicate in section 2.3.3, as occasion
demands.
•
Protection from motor over current (OCR)
This device activates and applies appropriate control when the current equal to or higher than
the set level flows. In some cases, this device stops the compressor operation.
For more information about setting and installation of this device, please refer to the instruction
manual of the motor.
•
Protection from oil level decrease
In case of the oil supply by differential pressure, install a protection device to the oil separator
for protect form oil level decrease. Since there is a possibility that alarm for protection from
lubricating differential pressure decrease does not activate even if the amount of lubricating oil
is insufficient.
•
No Water Alarm
If you use water cooling oil cooler and/or water cooling condenser, a suspension of water
supply protection is necessary.
For more information about setting and installation of this protection device, please refer to the
instruction manual of the motor or the like used in the cooling water system.
 Connection Positions and Settings
Specify the connection position and setting for each compressor protective device, and make sure
to provide users of this product with them.
 Inspection Method/Interval
Compressor protective devices require operation tests and confirmation of the settings calibration
before commissioning as well as at regular intervals.
Specify the inspection methods/intervals of the compressor protection devices, and make sure to
provide users of this product with such information.
 In the operation test, check that alarms and switches operate normally by using
devices such as pressure tester. Do not operate the compressor with all the valves
closed, or in any other dangerous conditions.
 If the protection from oil pressure (OP) or high pressure (HP) activates, do not restart
operation until the cause of activation is removed.
Screw Compressor i-series
1-7
2203M4JE-MY-iS2-N_2017.04.
Chapter 1 Safety
1.4 Safety Devices