ABB REL 551 2.3 Series - Page 42

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Checking the power supply &KDSWHU
&KHFNLQJWKHH[WHUQDOFLUFXLWU\
 &KHFNLQJWKHSRZHUVXSSO\
Check that the value of the auxiliary supply voltage remains within the permissible
range under all operating conditions. Check that the polarity is correct.