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SAFETY TESTERT O S 7 2 1 0 S

S A F E T Y( S P E C 8 0 7 7 6 )T E S T E R

PID Insulation Tester(Potential Induced Degradation)

TOS7210S

Capable of setting within the range of 50 Vdc to 2000 Vdc (resolution 1 V)
Ability to switch the applied voltage polarity instantly by the switch on the front panel
The output is floating from the ground potential.
Capable of measuring the current value between measurement points.

To evaluate the PID effectof the PV module!
**Potential Induced Degradation

PID Insulation Tester

TOS7210S [SPEC80776]
The PID insulation tester (TOS7210S) is designed based on the insulation resistance tester (TOS7200) to carry out theevaluation of the PID (Potential Induced Degradation) effect of the PV module precisely and efficiently. Being equippedwith the output ability of 2000 V and the ammeter with nA resolution as well as a polarity switching function, the TOS7210S
is also applicable not only to the PID evaluation but also the evaluation of the insulators that requires a high sensitivity ofmeasurement. The tester is equipped with the panel memory that is externally accessible and RS232C interface as standard;
it can be flexibly compatible with the automated system.

Conceptual diagram of test
Connects TOS7210S andthe solar cell modulewith an attached shield cable.

Back sheet
terminal box

Connection to
the solar
cell frame

Connecting the positive polarity andthe negative polarity of the terminal box as one unit

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Capable of arbitrary settingof the output voltage

Polarity switching function

You can set the test voltage that is applied
to the DUT within the range of 50 Vdc to 2000 Vdc(resolution 1 V). In addition, an insulation resistancetest of the electricity/electronic components orthe electricity/electronic devices is also
possible besides the voltage
specified in JIS C 1302:1994.
In the range of 50 V to 1000 V,
the output properties are complied to JIS C 1302:1994.

You can easily change the output polarity
by the switch on the front panel.
The PID deterioration is a reversible phenomenon
that may recover after the reverse bias voltage is applied.
The polarity switching is a convenient functionthat can avoid a wiring change that connects
to the DUT. In addition, switchingby the external control throughthe RS232C interface is also possible.

PID effect
The PID effect is a phenomenon that the amount of power generation by acell remarkably decreases when high voltage is applied between the solar
cell and the frame for long hours. It is supposed that the higher the applied
voltage is and/or the higher and more humid the environment is, the further
deterioration accelerates. For example, the potential difference in the string
becomes extremely higher when the number of sheets that are connected inseries increases even if the output voltage of the crystalline silicon solar cell
module is just tens of volts. On the other hand, the grounding methods of the
PCS (Power Conditioning System) that connects to the system as an AC power
supply varies according to the type of PCS. In recent years, the transformerlessmethod, where the input side is in the floating method (the negative polarity
is not connected to the ground) is increasing. In this case, a high potential
difference occurs between the cell and the ground. Regarding the crystalline
silicon solar cell module, it is proved that the cell having a higher negativeelectric potential than that of the frame (ground) easily causes the PID effect.
(See Fig. 1) The PV modules are currently managed with the maximum system
of voltage as 600 V in Japan and 1000 V in Europe. There is a market trend thatthe maximum voltage of the commercial mega solar system is raised from theperspective of reducing the number of the strings and the total number of the
PCS, and improving the efficiency of power generation.

[Fig. 1]
Positivepolarity

Frame

StringElectrode interval
Potential difference
Approx. 360 V

PCS

SystemPanel interval
Potential difference
Approx. 40 V

Negativepolarity

Frame[Fig. 2]White tempered glass
Na+

Surface electrodeAnti-reflection film

（Anti-Reflection）

Na+

Na+

Na+

Na+

Na+
+ Na+

Na

Cell
Back side electrodeSealing material (EVA)
Back sheet

Actualsize

Figure 2 shows the simulation of a crystalline silicon solar cell
module being exposed to a high potential difference. It isconsidered that, in the PID effect of the crystalline silicon solar
cell module, the sodium ion in the white tempered plate glass
moves to the side of the cell and then causes the deterioration.
(The PID effect of the thin film solar cell module is also
confirmed, however, the mechanism of the deterioration isdifferent from that of the crystalline silicon solar cell module.)
The cause of the PID effect is currently being tested with andresearched by various research organizations.

The output is floating from the ground.

Analog output terminal

The output terminal is floating from theground electric potential. *1
In addition, a shield cable is adopted as an output cable.
Therefore, it can be measured only an electric current flowing
between test points excluding the one between
the DUT and the ground, and it realizes to conduct
the highly-sensitiveand precise evaluation.

In the resistance display mode,the voltage depending on the measured resistanceis logarithmically compressed and output
within the range of 0 V to 4 V.
In the current display mode, the current is output in a
linear scale depending on the measured current andranges of measurement (4 ranges).
You can analyze the changes or the deterioration
status of the DUT by using an external recording
device such as the data logger.

*1: Ground voltage of the terminal that polarity is set as an anode (± 1000 Vdc)
Ground voltage of the terminal that polarity is set as a cathode(+1000 Vdc and -3000 Vdc)

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Information related to PID test

Reference: National Institute of Advanced Industrial Science and Technology■ Test on the PID effect
The experiment to reproduce the PID effect was conducted as the collaborative research theme in "Stage II Consortium of high-reliability
PV module development and evaluation" that was established in April 2011 by the Research Center of Photovoltaic Technologies, National
Institute of Advanced Industrial Science and Technology (hereinafter called "AIST"). Kikusui Electronics Corp. developed TOS7210S as anecessary test equipment contributed for this experiment project.
*The contents mentioned above was announced in the 61st academic lecture of Japan Society of Applied Physics on March 19, 2014.

■ Creation of the single cell module
The 6-inch polycrystalline silicon cell of the test module is laminated, as a unit cell module,with white tempered glass, ethylene vinyl acetate (sealing material), and back sheet.

● Materials used for a solar battery module
Cell substrate

6-inch polycrystalline silicon cellLight-receiving glass

White tempered glass

Sealing material

Ethylene vinyl acetate (EVA)

Back sheet

PVF/PET/PVF constituted back sheet▲ 6-inch polycrystalline silicon / unit cell module■ Test method
We installed the light receiving surface of the glass covered with an aluminum board in a constant temperature chamber and connected it to
the PID insulation tester TOS7210S. We then kept the module temperature at 85 °C and applied -1000 Vdc, -1500 Vdc, and -2000 Vdc to eachof three pieces of the single cell modules.
▼ Method of connecting the PV module(solar panel) and TOS7201S

Aluminum board +▼ Module in the temperature chamber▼ Leakage current andtemperature graph of the module

Conductive rubber sheet

White tempered glass-

Polycrystalline silicon cell

EVA

Back sheet■ Confirmation of the output characteristics by the solar simulator
An output drop can be confirmed with the initial (Pmax/F.F./Isc /Voc) characteristics of the module and the changes with the elapsed time.

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Maximum power P max

Fill factor F.F

Short circuit current I sc

Open circuit voltage V oc

▲ Applied voltage andmaximum power▲ Applied voltage and F.F▲ Applied voltage andshort circuit current▲ Applied voltage andopen circuit voltage

Information related to PID test

Reference: National Institute of Advanced Industrial Science and Technology■ Confirmation of the deterioration by EL (electro-luminescence)
The normal part emits light perfectly, but as
the deterioration accelerates, the shaded area
increases eventually and ceases to emit light.
This method is adopted useful to confirm the
PID effect. In addition, it is admitted that thedeterioration in the PID effect is reduced with theelapled time by a reversible effect or recovered
nearly to the initial state.

NormalNormal (recovered)

Deteriorated

Deteriorated

Result of EL test

Reversible effect (exposed indoor)■ Confirm the difference in deterioration by applied voltage
The ratio that the maximum electricity (Pmax) of the module decreases when the applied voltage increases. In addition, as the EL image
indicates, the higher the applied voltage becomes, the shaded area in the EL image increases in the same interval.

■ Recovery examination and the results by applying the reverse voltage▼Recovery of the sample that output drops by -99 % and less in the PID experiment+1000 V

+1500 V

+2000 V

▼Recovery of the sample that output drops by -65 % to -71 % and less in the PID experiment

In the PID ef fect af ter c onducting thereversible effect test, it may be found thatthe deterioration is reduced or recovernearly to the initial state in some module
by being lef t or the reverse voltage isbeing applied. The polarity can be easilychanged in TOS7210S with the switch.
You are not bothered by the complicatedconnection to the DUT. The module that
the Pmax drops remarkably (less than -99%), and the recovery is not confirmed evenafter applying voltage for long hours. On
the other hand, the module that the Pmax
drops moderately (approximately -53 % to-71 %) recovered almost perfectly in 0.5 totwo hours. In addition, it canbe recovered
regardless of the applied voltage.
Output lowered+1000 V

+1500 V

-99 % and less

-65 to -71 %-53 to -58 %200 hours later

2 hours later

2 hours later+2000 V

▼Recovery of the sample that output drops by -53 % to -58 % and less in the PID experiment+1000 V

+1500 V

+2000 V

Result of EL test after recovery test

■ Various evaluation methods
Under the present conditions, any of the evaluation test method or the standard are not established.
Each of the research organizations, experiment stations, and module manufacturers in the various countries conducting its own evaluation.
: Method to apply the water on the module glass surface and apply the voltage● Water method● Chamber method : Method to manage temperature and humidity in the temperature chamber and apply the voltage● Aluminum method : Method to cover the glass with an aluminum foil or let an aluminum board adhere to the glass surface, and apply the voltage
We continue experiments in each test method to examine each superiority and inferiority, difference by the temperature or humidity for future
standardization. The international standard IEC is devising the test method for the PID effect.
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■Specifications
Output section
Output voltage range

50 V to 2000 V

Resolution

1V

Accuracy± (1.5 % of setting + 2 V)

Maximum rated output

2 W (2000 V/1 mA)

Maximum rated current

1 mA

Outputterminals

Output type

Floating

Isolation voltage± 1000 Vdc (The terminal that polarity is set to positive polarity)+ 1000 Vdc and -3000 Vdc (The terminal that polarity is set to negative polarity)

Ripple2000 V/under no load

20 Vp-p or lessMaximum rated load

20 Vp-p or less

Voltage regulation

1 % or less (maximum rated load → no load)

Short-circuiting current

2 mA or less (250 mA or less instantaneous)

Output rise time

50 ms or less (10 % to 90 %, no load)

Discharge function

Forced discharge at the end of test (discharge resistance: 20 kΩ)

Voltmeter
Measurement range

0 V to 2400 V

Resolution

1V

Accuracy± (1 % of reading +1 V)

Resistance meter
Measurement range

0.01 MΩ to 5000 MΩ (In the range of over 100 nA to a maximum rated current of 1 mA)

Display□.□□MΩ [R < 10.0 MΩ]□□.□MΩ [10.0 MΩ ≤ R < 100.0 MΩ]□□□MΩ [100.0 MΩ ≤ R < 1 000 MΩ]□□□□MΩ [1 000 MΩ ≤ R ≤ 5 000 MΩ](R = measured insulation resistance)

Accuracy *1±(10 % of reading) [100 nA < i ≤ 200 nA]±(5 % of reading) [200 nA < i ≤ 1 μA]±(2 % of reading) [1 μA < i ≤ 1 mA](i = measured output-voltage value/measured resistance value)

Measurement range

The current measurement range is selectable between AUTO and FIX.

AUTO

Automatically changes the current measurement range according to the current for measuring resistance.

FIX

Fixes the current measurement range based on the output voltage set value and LOWER set value(in W COMP OFF status)

Holding function

Holds the resistance value obtained at the end of testing while a PASS judgment is being output.

Ammeter
Measurement range

0.000 μA to 1900 μA

Display□.□□□μA [i< 10.00 μA]□□.□□μA [10.00 μA ≤ i< 100.0 μA]□□□.□μA [100.0 μA ≤ i< 1 000 μA]□□□□μA [1 000 μA ≤ i]
(i =measured current value)

Accuracy *2±(4 % of reading +0.005 μA) [i< 10.00 μA]±(4 % of reading +0.005 μA) [10.00 μA ≤ i < 100.0 μA]±(2 % of reading +0.005 μA) [100.0 μA ≤ i < 1 000 μA]±(2 % of reading) [1 000 μA ≤ i]
(i =measured current value)

Measurement range

The current measurement range is selectable between AUTO and FIX.

AUTO

Automatically changes the current measurement range according to the measured current value.

FIX

Fixes the current measurement range based on the output voltage set value and LOWER set value(in W COMP OFF status)

Judgment function
Judgement
UPPER FAIL Judgement
method/action
LOWER FAIL Judgement

If a resistance value equal or less than the lower resistance is detected,
the tester shuts off the output and returns an UPPER FAIL judgment.
If a resistance value equal or less than the lower resistance is detected,
the tester shuts off the output and returns a LOWER FAIL judgment.
Note that no judgment is made within the judgment wait time (WAIT TIME) after the start of the test.

Time
Setting range for the test duration (TEST TIME) 0.5 s to 999 s (TIMER OFF function provided)
Setting range for the wait time (WAIT TIME)

0.3 s to 10 s (TEST TIME > WAIT TIME)

Accuracy±(100 ppm +20 ms)*1. Humidity: 20 %rh to 70 %rh (no condensation). No bends in the test leads.
*2. Humidity: 20 %rh to 80 %rh (no condensation). No bends in the test leads.
Humidity 20 %rh to 70 %rh when either of terminal A or terminal B is grounded (no condensation). No bends in the test leads.

6■Specifications
SIGNAL I/O
Input
specifications

Outputspecifications

D-SUB 25-pin connector on the rear panel
High-level input voltage

11 V to 15 V

Low-level input voltage

0 V to 4 V

Low-level input current-5 mA maximum

Input time width

5 ms minimum

Output method

Open collector output (4.5 Vdc to 30 Vdc)

Output withstand voltage

30 VdcOutput saturation voltage

Approx. 1.1 V (at 25°C)

Maximum output current

400 mA (TOTAL)ANALOG OUT

All input signals are active Low controlled.
The input terminal is pulled up to +12 V using a resistor.
Opening the input terminal is equivalent to inputting a high-level signal.

Outputs the measured resistance, measured current and voltage, and current range in DC voltage.

Measured resistanceRx
Rx: Resistance measurement)
1 MΩ
Rx (1 MΩ: 0.30 V, 10 MΩ: 1.04 V, 100 MΩ: 2.00 V, 1000 MΩ: 3.00 V, 10000 MΩ or more: 4.00 V)
Output impedance: 1 kΩ

Vo = log ( 1 +Measured current

Range 1: Vo[V] = measured value [μA] / 512
Range 2: Vo[V] = measured value [μA] / 64
Range 3: Vo[V] = measured value [μA] / 8
Range 4: Vo[V] = measured value [μA]COM

Analog output-circuit common

Accuracy±(2 % of full scale)

RS232CD-SUB 9-pin connector on the rear panel (compliant with EIA-232-D)
All functions other than the POWER switch and KEY-LOCK

Baud rate

9600/19200/38400 bps (data: 8 bits; parity: none; stop bit: 2 bits fixed)

REMOTE

6-pin mini-DIN connector on the front panel
The optional remote controller RC01-TOS or RC02-TOS is connected to control remotely
starting/stopping of a test (note that a DIN-mini DIN adapter is required).

Display

7-segment LED, 4-digit voltage display, 4-digit insulation resistance display, 4-digit current display,and 3-digit time display

Memory function
TEST MODE

A maximum of 10 types of test conditions can be stored in memory
MOMENTARY

A test is conducted only when the START switch is pressed.

FAIL MODE

Disables cancellation of FAIL judgment using a stop signal via remote control.

DOUBLE ACTION

Starts a test only when the STOP switch is pressed and the START switch is pressed withinapproximately a half-second.

PASS HOLD

Allows the time of holding PASS judgment to be set to 0.2 s or HOLDKEYLOCK

Places the tester in a state in which no keystroke other than the START/STOP switch is accepted

Environment
Installation location

Indoors and at altitudes up to 2000 m

Warranty range

Temperature/Humidity

15 °C to 30 °C (59 °F to 86 °F)/ 20 %rh to 80 %rh (no condensation)

Operating range

Temperature/Humidity

0 °C to 40 °C (32 °F to 104 °F)/ 20 %rh to 80 %rh (no condensation)

Storage range

Temperature/Humidity-20 °C to 70 °C (-4 °F to 158 °F)/ 90 %rh or less (no condensation)

Power requirements
Nominal voltage range(allowable voltage range)

100 Vac to 240 Vac (85 Vac to 250 Vac)

Power consumption

30 VA maximum

At rated load

Allowable frequency range

47 Hz to 63 Hz

Insulation resistance

30 MΩ or more (500 Vdc) [between AC LINE and the chassis]

Hipot

1500 Vac for 1 minutes, 10 mA or less [between AC LINE and the chassis],3000 Vac, 1 minutes [between A, B terminal and the chassis]

Ground bond

25 Aac/ 0.1 Ω or lessDimensions((maximum) (mm (inch))/ Weight214 (8.43") W × 81(3.19") (115 (4.53")) H × 340 (13.39") (385 (15.16")) D/ Approx. 2 kg (Approx.4.41 lbs)

● Rear panel● Accessories: Shielded cable

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Phone:(+81)45-593-0200, Facsimile:(+81)45-593-7591, https://global.kikusui.co.jp/

Printed in Japan■ All products contained in this catalogue are equipment and devices that are premised on use under thesupervision of qualified personnel, and are not designed or produced for home-use or use by general consumers.
■ Specifications, design and so forth are subject to change without prior notice to improve the quality. ■ Productnames and prices are subject to change and production may be discontinued when necessary. ■ Product names,
company names and brand names contained in this catalogue represent the respective registered trade name ortrade mark. ■ Colors, textures and so forth of photographs shown in this catalogue may differ from actual products
due to a limited fidelity in printing. ■ Although every effort has been made to provide the information as accurate
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Issue:Nov.2022 202211PDFEC21