Operation Manual

09/ 2012 BENNING PV 1-1
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8.3 Automatic measurement of the open-circuit voltage, short-circuit current and insulat-
ing resistance of the PV generator
c
The PV module/ PV string must not exceed the maximum opencircuit voltage
of 1000 V DC, the maximum short-circuit current of 15 A and the maximum DC
power (P = U x I) of 10 kW.
According to DIN EN 62446, the measurements have to be made for each PV string.
Measurements made at PV strings which are connected in parallel might in-
volve an overload of the BENNING PV 1-1.
m
During the insulating resistance measurement, the PV generator is shorted.
Measurement is made between the red 4 mm test socket and the shorted PV
test sockets.
m
In case DC polarity is wrong or DC voltage is within the range of < 5 V or
> 1000 V, it is not possible to make an automatic PV measurement.
- Connect the BENNING PV 1-1 to the PV module or the PV string by means of the enclosed
PV safety measuring leads.
- For insulating resistance measurement, connect the red safety measuring lead of the 4 mm
test socket L to a metal part (frame or mounting system) of the PV generator.
- If the PV generator is properly earthed by means of an earthing conductor, the red safety
measuring lead of the 4 mm test socket L can be connected alternatively to a safe earth
connection (equipotential busbar).
- Measurement of the PV open-circuit voltage is made automatically, if a DC voltage is applied
to the PV safety measuring leads (test sockets
9
and
J
).
- In case of reversed polarity of the DC voltage, the polarity indication is flashing and the
symbol E is displayed. Automatic measurement will be blocked until the polarity of the DC
voltage is correct.
- As soon as a voltage of > 30 V is applied to the PV safety measuring leads, the
c
warning
symbol F (Attention, dangerous voltage) is flashing.
- In order to set the testing voltage for measuring the insulating resistance , press the
V
ISO
-key
5
and select the desired testing voltage (250 V, 500 V or 1000 V DC).
- Press the
Auto
-key
3
to start the automatic PV measurement. The following measurements
will be made:
- measurement of the PV open-circuit voltage
- measurement of the PV short-circuit current
- measurement of the insulating resistance
- The measured values will be shown on the display
1
for approx. 20 seconds or until a key
is pressed.
- If the measured insulating resistance is higher than the preset limiting values, the sym-
bol will be displayed next to the insulating resistance value. If the insulating resistance value
is lower than the limiting values, the symbol will be displayed.
See gure 6: Automatic solar panel measurement, ISO measurement via earthing conductor
Preset limiting values:
V
ISO
Limiting value of insulating resistance
250 V 0.5 MΩ
500 V 1.0 MΩ
1000 V 1.0 MΩ
8.4 AC/ DC voltage measurement
- Disconnect the PV safety measuring leads from the PV test sockets
9
and
J
.
- Connect the red and black safety measuring lead to the corresponding 4 mm test sockets K
and L.
- Connect the measuring probes to the voltage source to be measured.
- The BENNING PV 1-1 automatically measures the voltage at the measuring probes.
- The polarity of the DC voltage is displayed by “+ / –“ A. In case of AC voltage, “+ / –“ A will
be displayed alternately.
See gure 7: Voltage measurement via 4 mm test sockets
8.5 Current measurement by means of optional AC/ DC current clamp adapter
BENNING CC 3 (part no. 044038)
By means of the optional AC/ DC current clamp adapter BENNING CC 3, the BENNING PV 1-1
can be used to measure the operating current of a PV system. The determined current values
can be stored in the internal memory of the BENNING PV 1-1 and can be recalled.
- Disconnect all measuring leads from the BENNING PV 1-1.
- Connect the BENNING CC 3 current clamp adapter to the 4 mm test sockets K and L of