Specifications 33
Note:
Option PV
WattNode models may not meet these accuracy specifications for the
P3
output channel when measuring a two-phase inverter or multiple inverters.
Pulse Outputs
Factory Programmable Full-Scale Pulse Frequencies:
Standard (All Models):
4.00 Hz
Custom (Bidirectional Output Models):
0.01 Hz to 600 Hz
Custom (Option P3, Option PV, Option DPO):
0.01 Hz to 150 Hz
Absolute Maximum Pulse Output Frequencies:
Standard Models (Bidirectional Outputs):
900 Hz
Option P3, Option PV, Option DPO:
200 Hz
Output Waveform:
square-wave, ~50% duty cycle
Option PW:
programmable pulse
ON
(closed or conducting period, 1 to 65535 milliseconds
Optoisolator Outputs:
Isolation:
5000 Vac RMS
Breakdown Voltage (collector–emitter):
60 V (exceeding this may destroy the outputs)
Maximum Reverse Voltage (emitter-collector):
5 Vdc (exceeding may destroy the outputs)
Maximum Leakage (OFF) Current (collector–emitter):
100 nA
Recommended Load Current (collector–emitter):
1 μA (microamp) to 5 mA (milliamp)
Maximum Load (collector–emitter) Current:
~8 mA
Approximate ON Resistance (as measured by a DMM):
100 Ω to 2000 Ω
Approximate OFF Resistance (as measured by a DMM):
> 50 MΩ
Measurement
Creep Limit:
0.10% (1/1000th) of full-scale. Whenever the real power for a phase drops below the
creep limit, the output power (real) for the phase will be forced to zero. Also, if the line voltage
for a phase drops below 20% of nominal Vac, the output power for the phase will be set to
zero. These limits prevent spurious pulses due to measurement noise.
Update Rate:
~200 milliseconds. Internally, the consumed energy is measured at this rate and
used to update the pulse output rate.
Start-Up Time:
approximately 500 milliseconds. The meter starts measuring power and generat-
ing pulses 500 milliseconds after AC voltage is applied
Default Current Transformer Phase Angle Correction:
0.0 degrees
Over-Voltage Limit:
125% of nominal Vac. If the line voltage for one or more phases exceeds this
limit, the status LEDs for these phases will flash alternating red-green as a warning. Extended
over-voltage operation can damage the meter and void the warranty. See
.
Over-Current Limit:
120% of rated current. Exceeding 120% of rated current will not harm the
WattNode meter but the current and power will not be measured accurately.
