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Verification of Installation
Once the MD-xxHD meter is configured and communicating with the RTU, it is a good idea to perform
some simple checks to ensure that all the CTs are on the correct voltage phases and that the CTs are
facing the correct direction. The following are recommendations that work for typical installations. Special
circuit conditions, like unloaded motors, may indicate an installation error when none exists. A Digital
Multimeter (DMM) can be used to confirm these cases.
Installation Phase Verification
The MD-xxHD meter includes a PhaseChek
™ algorithm that identifies any element that the meter
suspects may be incorrectly phased (i.e., the CT is associated with the wrong voltage source or is
physically on the wrong wire) based on power factors below 0.55. This feature is accessed using the LCD
interface by navigating to
VERIFY INSTALLATION and pressing the ENTER button. The LCD display will
list the elements having at least one channel with a low power factor.
CHECK ELEMENTS
A EF
Use the navigation buttons to highlight a specific element and press ENTER or just press ENTER and
move from element to element using the

/
→
keys. Within each element (identified on the top line of
the display) the status of each channel is identified as good (PF > 0.55) or bad (PF < 0.55).
ELEMENT F
CH1 Good
CH2 Bad
CH3 Bad
Two “Bad” channels are often an indication that two CTs are inadvertently swapped. When the power
factor for all enabled channels is greater than 0.55, the meter reports:
CHECK ELEMENTS
ALL CHANNELS GOOD
PhaseChek
™ is only applied for elements that are enabled. VIEW METER SETUP on the LCD
screen can be used to ensure that all intended elements are active. PhaseChek
™ is advisory
only. It is possible that the power factor for a particular load is truly less than 0.55, as may be
observed in a free running motor.
The ViewPoint HD and the MD-xxHD Web App run PhaseChek
™
continuously on all enabled elements
and report low power factor in the real time values table by turning the text RED or by a using a red
indicator.