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What can cause a Series 2000 Circuit Monitor to have an alarm code "900" on the display?

Issue
A CM2000 Series meter's front display shows an alarm code "900" and user may not know what this means or how to fix it.

Product Line
CM2000, CM2050, CM2150, CM2250, CM2350, CM2450

Environment
Alarm code, Error Message, Power meter retrofit and replacement
 
Cause
Alarm "900" can occur when there is a potential voltage difference between the ground and neutral control power connection on a Series 2000 Circuit Monitor.  

Resolution
*Warning:  Installation and maintenance of this device should only be performed by qualified, competent personnel that have appropriate training and experience with high voltage and current devices. Failure to follow the instructions / warnings in the Meter Installation Guide can result in permanent damage to the meter, severe injury or death.

Follow the three steps below:
1.  First use a handheld meter to verify that a potential difference between the Neutral and Ground terminal exist (terminals 26 and 27).

2.  To correct the issue verify that the neutral and ground are bonded together at the incoming source from the utility.  
3.  Make sure that the enclosure is grounded and the meter is grounded to the metal enclosure. 
4.  The unit will need to be replaced if the display still has a "900" on the display after verifying and correcting the steps above. 
 
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