About the Waveform/Values screens
PV Wave + Value screen
Estimate Power screen
Equations
w1: Power (kW) = Voltage (Ch. 1-1) × current (Ch. 1-2)
w2: Power integration (kWh) = Voltage (Ch. 1-1) × current (Ch. 1-2) × measurement time (h)
w3: Estimated power (kW) = Insolation strength (Ch. 1-3) / Gs (standard test condition of 1 kW/m
2
) × (1 + temperature loss*1) ×
(1 - coefficient for other losses) × photovoltaic cell rated output (kW)
w4: Estimated integration (kWh) = Insolation strength (Ch. 1-3) / Gs (standard test condition of 1 kW/m
2
) × (1 + temperature loss*1)
× (1 - coefficient for other losses) × photovoltaic cell rated output (kW) × measurement time (h)
w5: AC estimated power (kW) = Estimated power (w3) × power conditioner conversion efficiency (reference value)
w6: AC estimated integration (kWh) = Estimated energy (w4) × power conditioner conversion efficiency (reference value)
w7: Estimated power approximation rate (%) = Energy (w2) / estimated energy (w4)
* 1 Temperature loss = Photovoltaic cell maximum output temperature coefficient × (panel temperature (Ch. 1-4) - 25) / 100
* The estimated energy is calculated for reference purposes using JIS C8907:2005, “Estimation Method of Generating Electric Energy
by PV Power System.”
* In the state of "PV mode Set ON", the range of ch1-1 to ch1-4 and w1 to w7, scaling, an upper and lower limit, and a comment are
set up automatically. Moreover, the range of ch1-5 to ch1-11 set up on the "extended channel set" screen, scaling are also set up
automatically.
Note
The results of calculations performed by the instrument to yield estimated power, estimated integration, estimated power
approximation rate, AC estimated power (reference values), and AC estimated integration (reference values) are easily influenced by
the manner in which the target solar panels were installed as well as weather conditions and panel degradation. Calculated values
should be considered as guidelines for solar panel maintenance, rather than guaranteed values.
Measurement Procedure
1. Select “PV Mode Set ON” on the Measurement Settings screen.
-1. Press the “SET” key and select “PV Mode Set ON” on the
Measurement Settings screen.
2. Connect the sensors to the LR8400-23.
-1. Ch.1-1:
•
Connect the BNC conversion cable(2.4m) to the BNC side of the 9322 Differential Probe and connect
the 9804-01 Magnet Adapter (red) and the 9804-02 Magnet Adapter (black) to the ends.
•
Connect the BNC conversion cable to Ch.1-1.
•
Connect the power cord to the power jack on the 9322 Differential Probe.
•
Connect the power cord’s positive wire to the +12 V jack on the external I/O terminal block on the LR8400-23, and similarly
connect the power cord’s negative wire to the GND jack.
-2. Ch.1-2:
•
Connect another BNC conversion cable(30cm) to the CT9692-90 (or CT9693-90) Clamp Sensor and connect it to Ch.1-2.
•
Set the CT6590 Sensor Unit’s range (H or L).
•
Check the AA batteries in the CT6590 Sensor Unit.
-3. Ch.1-3:
•
Connect the actinometer (EKO Instruments ML-01 or ML-020VM).
-4. Ch.1-4:
•
Connect the thermocouple.
3. Place the sensors (see Figures 1 and 2).
-1. Ch.1-1:
•
Connect the 9804-01 (red) and 9804-02 (black) magnet adapters that are connected to the tip of the 9322 Differential Probe to the
positive and negative terminals of the main DC line in the junction box or the electrical box (or when investigating a failed string,
the branch circuit) between the solar panels and the power conditioner. Cut the magnet sheet, pasted on the back of the 9322
Differential Probe.
-2. Ch.1-2:
•
Clamp the CT9692-90 (or CT9693-90) Clamp Sensor to the positive side of the main DC line in the junction box or electrical box
(or when investigating a failed string, the branch circuit). At this time, orient the current direction mark on the clamp sensor so that
it indicates a flow from the solar panels to the power conditioner.
-3. Ch.1-3:
•
Attach the actinometer (EKO Instruments ML-01 or ML-020VM) to the solar panel. So that it is parallel with the measurement
surface using the adjustment screw.
-4. Ch.1-4:
•
Attach the thermocouple to the solar panel.
LR8400-92
LR8400-93
PV Power Verifier
Instruction Manual (PV Mode)
December 2013 Revised edition 1
Printed in Japan
LR8400E981-01 13-12H
Thank you for choosing the Hioki LR8400-92/
LR8400-93. This Measurement Guide introduces the
basic method for measuring the
DC side
of a
photovoltaic system. For more information about
standard methods for using the instrument in
applications other than the above and general handling
information, please see the LR8400-20 Instruction
Manual.
Turn on the instrument.
1. Select “PV Mode Set ON” on the Settings screen.
2. Connect the sensors to the LR8400-23.
3. Place the sensors (when investigating a failed string, change the measurement
circuit inside the junction box).
4. Configure settings.
5. Check measured values on the Monitor screen.
6. Start time-series recording.
End measurement.
End recording.
Check and analyze saved data.
Turn off the instrument.
7. Investigate the failed string.
Measurement preparations
-1. Inspect the instrument.
-2. Insert a CF card (or USB flash drive)
into the instrument as necessary.
-3. Connect the AC adapter.
-4. Turn on the instrument.
1
4
Figure 1
Figure 2
The instrument provides the following
six Waveform/Values screens:
•
PV Wave + Value
•
PV Wave + Crsr
•
Gauge + PV Wave
•
PV Value
•
Estimate Power
•
AC Estimate (reference values)
