Checkout Current Transformers (CTs) and check resistance across each one while it is disconnected. All resistances should be within 10% of one another. Also do a diode test on the CT inputs on each compressor module. (The diode test is described in RTAA-SVB10B-EN.)
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[pdf] When pressing “Enter” the following interface will pop up and the password will be required (9999). NOTE: Customer Password can be modified in the CUSTOMER PARAMETER menu. Page 23 KRSD series ENTER PASSWORD ****. Page 24 UNLOAD P. *.**Mpa Unload pressure setting.
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