CCS WattNode Pulse WNB-3D-240-P, Reference Manual

Page: 21 / 38

Installation 21
Installation LED Diagnostics
The WattNode meter includes multi-color power diagnostic LEDs for each phase to help verify
correct operation and diagnose incorrect wiring. The LEDs are marked “Status” on the label. The
following diagrams and descriptions explain the various LED patterns and their meanings. The A,
B, and C on the left side indicate the phase of the LEDs. Values like “1.0sec” and “3.0sec” indi-
cate the time the LEDs are lit in seconds. In the diagrams, sometimes the colors are abbreviated:
R = red, G or Grn = green, Y = yellow.
Normal Startup
On initial power-up, the LEDs will all light up in a red,
yellow, green sequence. After this startup sequence, the
LEDs will show the status, such as
Normal Operation
below.
Normal Operation
During normal operation, when positive power is measured
on a phase, the LED for that phase will flash green. Typical
flash rates are shown below.
Percent of Full-Scale Power LED Flash Rate Flashes in 10 Seconds
100% 5.0 Hz 50
50% 3.6 Hz 36
25% 2.5 Hz 25
10% 1.6 Hz 16
5% 1.1 Hz 11
1% (and lower) 0.5 Hz 5
Table 4: LED Flash Rates vs. Power
Zero Power
For each phase, if line Vac is present, but the measured
power is below the minimum that the meter will measure (see
Specifications - Measurement - Creep Limit ), the meter will display solid green for that phase.
Inactive Phase
If the meter detects no power and line voltage below 20% of
nominal, it will turn off the LED for the phase.
Negative Power
If one or more of the phase LEDs are flashing red, it
indicates negative power (power flowing into the grid) on
those phases. The rate of flashing indicates magnitude of
negative power (see
Table 4 above). This can happen for
the following reasons:
●
This is a bidirectional power measurement application, such as a photovoltaic system, where
negative power occurs whenever you generate more power than you consume.
●
The current transformer (CT) for this phase was installed backwards on the current carrying
wire or the white and black wires for the CT were reversed at the meter. This can be solved
by flipping the CT on the wire or swapping the white and black wires at the meter.
●
In some cases, this can also occur if the CT wires are connected to the wrong inputs, such
as if the CT wires for phases B and C are swapped.
1.0sec 1.0sec 1.0sec
Green Yellow Red
Green Yellow Red
Green Yellow Red
C
B
A
Green Off Green Off Green Off
Green
Off
C
B
A
Red Off Red Off Red Off
Red Off Red Off Red Off
Red Off Red Off Red Off