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Installation
Checking Phases
57
Building Technologies
125-202
06/06/2017
Checking Phases
The Phase LEDs are a unique feature of the MD-BMS and MD-BMED Power Meters
that simplify installation by ensuring proper CT-to-phase installation and avoiding faulty
data collection. The meters automatically adjust for CT orientation—reducing setup
time and nearly eliminating installation errors.
Verifying the MD-BM and MD-BMS Power Meter
Setup Using the LEDs
The MD-BMS and MD-PMED Power Meters have three bi-color LEDs for each
element. These LEDs provide the following information:
●
All LEDs are green — the system power factor is greater than 0.55 and the CTs
are properly placed on the corresponding voltage phases.
●
Any one LED is red — there is a phasing connection error.
●
Two LEDs are red and one is green — two CTs are reversed.
●
All three LEDs are red — all CTs are incorrectly connected.
NOTE:
If the total system power factor is less than 0.55, the LEDs are red even if connected
properly. This situation is rare but can occur if, for example, the load to be monitored
is a lightly loaded electric motor where it is common for the power factor to be less
than 0.55 and the corresponding LEDs will be red.