Electrical safety
in Photovoltaic Systems

Types of system

Requirements in the standards

Protection against electric shock

PV generator earthing

Inverters
Regenerative 2011 H.Potdevin
Key-Account OEM
Personal:
Technical Data:
Age:
Family:
Profession:
Personal record:
Holger Potdevin
45
Martina my wife and 2 sons Jonas(17), Nils(8)
Dipl.-Ing. Electronics
1991-1992 Development dep. BENDER
1992-1994 Region sales Hamburg/SH
1994-1996 Inside sales group north
1996-2000 Product manager hospital-market
2000
Sales leader ESB
2000-2009 SCHROFF GmbH Sales-office Hessen
2009- Back “at home” BENDER Key-Account
2
The future of the supply of electrical power
The efficient, appropriate usage of nature's resources is the objective of all operators,
independent of whether with solar, wind, water or biogas installations.
Bender provides reliable solutions proven worldwide to

Detect possible electrical hazards at an early stage

Ensure the safety of personnel and installations

Immediately detect critical operating states and installation states

Reduce risks of failure and service interruptions to a minimum

Ensure high installation availability by means of preventive action

Efficiently manage installation data.
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 3
Wind-Power-Generators: Default Frequency
by affected components
electrical system
control
hydraulics
rotor blades
gear drive
power train
generator
‚Windenergie Report Deutschland‘ 2008, by ISET Kassel
Wind-Power-Generators: Monitoring Solutions
 1-Insulation Monitoring in main circuit
 2-Insulation Monitoring in control circuits
 3-RCM in yaw-drive
 4-RCM in pitch-drive
 5-voltage/frequncy monitoring
 6-communications
The future of the supply of electrical power
Source: Prof. Strunz, www.sense.tu-berlin.de
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 6
More yield and return for PV installations
 For a high return on a PV installation
 Lots of sunshine
 Good planning
 Protective measures compliant with the standards
 High quality components
 Thorough installation monitoring
 Safeguarding the predicted yield
over the entire life of the installation requires:



The necessary monitoring systems and safety features, compliant
with the standards (e.g. insulation monitoring)
Increased reliability by means of the early detection of impending faults
The majority of the laws promoting the use of renewable energy are
based on the subsidised sale of the energy generated
 Installation failures lead to direct losses of revenue
(reduction in the funding quota and reduction in the return)
 Fault location: In case of a fault, appropriate
equipment eases quick localisation and rectification
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 7
Basis
 PV systems from some W up to MW
 Voltages from 12 V up to 700 V and more
 Earthed and unearthed PV generators
 Earthed and unearthed module frames of the PV generators
 Inverters :
- with 50/60 Hz transformers
- Without transformers
- RF transformer
 Insuring the electrical safety for
- The general public
- Specialists (e.g. electricians)
- Emergency services personnel, e.g. fire brigade
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 8
Basic definitions
according IEC 60364-7-712 / DIN VDE 0100-712
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 9
Fire hazard in TN-Systems
PV-Generators 1/2
The
Bakersfield
Fire, by Bill
Brooks
Regenerative 2011 H.Potdevin
Fire hazard in TN-Systems
PV-Generators 2/2
The
Bakersfield
Fire, by Bill
Brooks
Regenerative 2011 H.Potdevin
Basic layout of a PV generator
 String
inverters
 Central
inverter
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 12
 Team
technology
 Medium voltage
application
Overview ISOMETER PV
Typ
isoPV485
IRDH275(B)49335
monitoring
peak-power
isoPV-board
isoPV-module
ungrounded/unearthed PV-systems
≤ 100 kWp
≤ 250 kWp
inverter
voltage
IsoPV +
AGH-PV-3
≥ 250 kWp
≤ 300 kWp
≥ 300kWp
inverter with galvanical separation
DC 0…1000 V
DC 0…650 V
DC 0…1100 V
DC 0…1000 V
DC 0…1500 V
max. leakage
capacitance Ce
≤ 100 µF
≤ 999 µF
≤ 2000 µF
≤ 350 µF
≤ 2000 µF
response value
10 kΩ (fix)
1 kΩ … 10 MΩ
0,2…100 kΩ
1, 2, 5, 10, 20, 50,
100 kΩ
200 Ω…1 MΩ
isoPV485







improved IR488
up to 1000VDC
up to 100µF leakage capacitance
fixed response value (10kΩ)
internal resistance 200kΩ
supply 12 - 72 VDC
new front design
 SOP: November 2011
Insulation monitoring device
A-ISOMETER® iso-PV 3
 A-ISOMETER ® iso-PV 3
universal insulation monitoring device for un-earthed systems
(IT systems) AC, AC / DC 0…793 V, DC 0…1100 V
- in conjunction with coupling unit AGH-PV3
A-ISOMETER ® iso-PV 3
 Optimal adaptation to the installation structure
due to two separately adjustable tripping values
(0.2 kΩ…100 kΩ) for pre-warning / main alarm
 Precise measurement of the insulation resistance
in all operating conditions
– such as voltage fluctuations / high system leakage
capacitances (up to 2000 uF) using patented AMPplus measurement technique
 Time-saving parameter setting
due to modifiable installation profiles
 Immediate information on device setting
and system leakage capacitance via information button
 Flexible signals
due to 2 separate alarm relays
 Ideal for installations with several inverters
operated in a team
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 15
Coupling unit AGH-PV-3
Insulation monitoring device
A-ISOMETER® iso-PV 3
Your advantages with an un-earthed power supply (IT system)




One service interruption per hour costs
approx. 8 % of the yield (KACO)
With IT system no service interruption
on 1st fault
Increased fire safety
 Insulation faults that occur are detected
and signalled at an early stage
Increased protection of personnel
 Only DC on PV modules, small AC ripple
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 16


The PV system has a high level of availability =
high yield
Insulation fault location in operation
 Shut down of the installation not
necessary = high yield
 Time and personnel significantly reduced
 Localisation of the insulation fault
down to the PV module
Insulation monitoring device
A-ISOMETER® iso-PV 3 – in applications operated in a team
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 17
isoPV-board
 pcb
 supply 9 – 40V DC
 connectors
 2 galv. separated outputs (PWM + Ok)
 galv. separated RS485-Interface
 mounting spots/DIN-rail clamps
 universal measuring-module
 2 LED (Ok, Alarm)
 button (Test, Reset)
 potentiometer for response value
 low-ohmic coupling hybrid (240 kOhm)
 size pcb: 171 x 84 mm
 size total: 175 x 90mm
 completely casted
 up to 350µF leakage capacities
 up to 1000V DC
 SOP: HMI 2012
isoPV-Modul (SMA): Layout
isoPV-Modul (SMA): Technical Details
Features:
 Insulation Monitoring for large PV-plants
 two response values (200Ω..1MΩ)
 automatical adjustment (learn)
 integrated PGH 50 mA
 integrated RCM
 connection monitoring
 self-test
 separated outputs for insulation-fault, system-fault, RCM-fault
 CAN, RS485, USB interfaces
 μSD-card-slot (data-logging)
 DC 1500 V
 internal resistance of 50 kΩ
 leakage capacities of up to 2000 μF
 SOP: Q1 2012
Erthfault detected – but where?
Regenerative 2011 H.Potdevin
Insulation fault location on the PV modules
Arrow marking on
the probes
 In PV systems it is normally difficult to
enclose both conductors with the probe
 To eliminate the effect of the load current
on the individual conductors, 2 probes are
used
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 22
Insulation fault location system EDS
Test device
PGH473
Measuring current
transformer series W …..
Insulation fault
evaluator EDS460-DG
Portable evaluation system
EDS 190
Your advantages
 More operational continuity and as a result
significantly more yield
 Recommendation for PV installations ≥ 100 kWp
in accordance with UTE
 Quick localisation of the insulation fault while
live = no shut down necessary
 Precise fault location - significantly less time required
compared to "inspecting the area"
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 23
RCMB100
RCMB100
Function

Universal AC/DC current sensitive differential
current monitoring module type B Effective value
measurement
(AC + DC)

Frequency range 0…500 Hz

Connection monitoring for the measuring current
transformer

The effective value of the DC components in the
differential current and the AC components under
the limit frequency is formed and provided as a
DC voltage proportional to the differential current
on the module output (X1).

Exceeding the measuring range is also signalled
via a switched output (X12).

In addition, the control input (X10) is polled.
Depending on the HIGH / LOW level sequence,
the RCMB100 is reset with / without subsequent
Starting procedure of transformerless
String-inverters
Bsp.:
80𝑚𝐴
2
+ (30𝑚𝐴)² = 85,44𝑚𝐴
IC
IF
ID
Regenerative 2011 H.Potdevin
 1- und 3-phasige
transformatorlose
Wechselrichter
 PIKO 3.0 .. 10.1
VMD424
 fits new requirements „medium voltage guidelines“, German public utilities
 frequency response values adjustable within 0,05-Hz range
 SOP: KW 38 2011
‚NA-Schutz‘ (grid-/plant-protection) according to VDE-AR-N 4105
 up to now:
- DIN V VDE V 0126-1-1, TAB,
„Niederspannungsrichtlinie“, etc.
VMD423
• from 01.01.2012: VDE-AR-N 4105:
•
•
•
•
•
„VMD4105“
additional requirements
functional safety
history for alarms with timestamp
new frequency response values
integrated and central grid-/plant-protection
BENDER PV Solutions
Type
Monitoring
PV-System typical
Type of inverter
RCM100B
Residual Current
earthed system
≤ 30 kWp
IRDH275(B)49335
Max. Leakage
capacitance
AC/DC
0…500 mA
IsoPV +
AGH-PV-3
Insulation resistance
unearthed system (IT system)
≤ 30 kWp
without
transformer
Nominal voltage
Response value
Measuring range
IR488
≤ 250 kWp
≥ 250 kWp
EDS473+
PGH471
VMD422
Insulation fault
location
IT system
Voltage,
frequency
asymetry
≥ 100 kWp
≥ 30 kWp
Inverter with built-in transformer
or external (MV) Transformer
Interface to
public low
voltage grid
DC 0…1000 V
DC 0…650 V
DC 0…1100 V
DC 20…960 V
≤ 30 uF
≤ 999 uF
≤ 2000 uF
≤ 500 uF
≤ 30 kΩ
1kΩ … 10 MΩ
0,2…100 kΩ
5 mA (10 kΩ)
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 28
3(N)AC 0-500 V
Thank you for your attention!
Dipl.-Ing. W. Bender GmbH & Co.KG
Londorfer Straße 65
35305 Grünberg
Germany
www.bender-de.com
Phone
+49 (0) 6401 807-280
Fax
+49 (0) 6401 807-279
E-mail
export@bender-de.com
Internet:
http://www.bender-regenerative.com

Copyright


Pictures: www.fotolia.de, www.pixelio.de, www.sma.de, www.fronius.de, Bender Archiv
Subject to change without notice - © Dipl.-Ing W. Bender GmbH & Co.KG, Germany
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We do not provide any guarantee or accept any liability for incorrect or omitted entries. All data are based on manufacturers' information. All logos and product names are registered trade marks of the related manufacturer.
© Bender · Germany · www.bender-de.com · F154(Photovoltaik)_PPT_en_20100714 Sellner · Nr. 29