Photovoltaics - the total solution from Weidmuller
27 June 2011
At Weidmüller, we offer a comprehensive range of power-saving and customised components that help increase efficiency, simplify plant monitoring and speed up maintenance in the photovoltaic sector. For protection against harsh environmental conditions and lightning protection, we have designed a dedicated range of fuse terminals and Stringboxes with Surge Protection devices and larger bespoke PV plant solutions are also available from our customer specific design team.
Varitector
Customised Surge Protection with bespoke String Box Configuration
Owing to their large surface area and exposed installation location, photovoltaic systems can be particularly at risk from atmospheric discharges such as lightning. Resulting damage can cause individual component damage or at its worst, take down the entire system.
An essential part of photovoltaic facility design is to therefore ensure protection from potential lightning discharge or power surges which could destroy critical items such as the inverter. Our plug & play surge protection solutions provide facility installers with a turn-key solution for protecting both the DC and AC sides on an inverter. If desired, the housing can also be equipped with a DC-load circuit breaker in order to disconnect the photovoltaic facility.
In addition, IP65 protection also guarantees protection against dust and splash water which means they are ideal for use in outdoor applications.
Based on individual requirements, string boxes can be configured, fully populated with the necessary fuses, terminal blocks and lightning and surge protection components as required, and wired up before they are delivered. If desired, the box can also be delivered with other connector types or cable glands.
PU II –Low voltage consumer device and electronics surge protection
Our PU II components are designed specifically to protect low voltage consumer devices and electronic appliances against overvoltage due to lightning or switching operations.
The PU II series are in full compliance of class II and III IEC 61643-1:2008 standards requirements, and type 2 and type 3 are in compliance with EN 61643-111 classes C and D as well as DIN VDE 0675, T.6, class C and D, T.6, A2 10/96. The series has a high energy absorption with I max 40 kA (8/20 um) and Uoc of 6 kV with a short response time.
With a compact, space-saving design, the high-power varistor is at the heart of the PU surge protection. The pluggable component has a thermal mechanism that triggers during a malfunction, with its indicator changing from green to red. The arrester can be simply swapped out without disconnecting the wiring, with easy and safe exchange due to coded modules and bases. The pluggable varistor modules are coded in compliance with their voltage and therefore it is easy to identify a replacement varistor. All of these features allow the PU modules to effectively reduce the interference coupling that can occur from surge voltages.
Signal protection with Varitector SPC remote signalling
Our pluggable VARITECTOR SPC product line (illustrated) combines superior protection characteristics and compact design, providing the ideal foundation for signal protection in photovoltaic applications.
The protection element of the module can be removed, measured or replaced during operation without affecting the impedance and without breaking the instrumentation circuit of the wiring.
With the VARITECTOR SPC R, error detection and failure indication are effected via internal monitoring with a green LED indicating active protection and a red LED standing for failure.
This information is forwarded to the V-Control evaluation module. From here it can be signalled, for instance, to a control unit. The V-TEST testing device, monitoring the function of VARITECTOR SPC also facilitates the observance of service intervals and the testing method complies with the IEC 62305 standard. As a result the defective module can be very quickly found and replaced. All VARITECTOR SPC products are in compliance with the IEC 61643-21:2008 surge protection product standard and are certified for protection classes D1, C2 and C3.
A VARITECTOR SPC module can be used instead of a modular terminal when removing the protection module, without affecting the impedance. Four binary or 2 analogue signals only require 17.8 mm of space on the mounting rail. Easy latching onto the earthed rail also saves time during installation. Colour codes mark the different voltage levels of all VARITECTOR SPC modules in the control cabinet thus facilitating service during operation.
An EMC-SET is available as an accessory, offering easy connection of the cable shielding to the tension clamp connections of the VARITECTOR SPC modules.
V-TEST test unit for standard-compliant inspection of pluggable surge protection devices
The V-TEST is a compact and portable testing device intended for the VARITECTOR SPC (measurement and control) and the PU1/PUII (power supply) surge protection solutions.
The unit can be used to carry out repeated testing in compliance with maintenance test intervals as specified in IEC 62305-3, and indicates the functional state of the components.
It takes a few simple menu steps to navigate directly to the measurement function. No adapter is required as the arresters are simply plugged into the compact test unit. Only a few simple movements are required to analyse the status of the arrester.
The backlit display shows the measured reading per component (GDT, MOV, TAZ) as OK or Not OK. This function allows you to detect ageing components by displaying possible damage right away allowing you to provide maximum protection.
The V-TEST is equipped with a charger, battery set and protective case which enables autonomous use in the field. It calibrates itself when it is turned on, ensuring that it can always deliver precise measurement and test values.