Leading power and automation technology group ABB has released new OTDC
switch disconnectors for DC applications up to 1,500 amperes (A). The disconnect
switches are ideal for disconnecting a solar inverter from the DC side and can
be used in combiner boxes for switching of individual PV arrays.
Featuring a unique two pole configuration for 1,000 V DC, the OTDC is
currently the only true 1,000 V DC per polarity switch on the market. The OTDC
portfolio now includes solutions for installations with special requirements
such as 1,500 V DC voltages, multi-circuit switching and combined load outputs
above 800 A.
With the latest release, ABB is bringing the benefits of compact design,
safe DC switching and low power losses of the OTDC products to photovoltaic
(PV) applications with higher amperages.
The OTDC switch disconnectors support the solar industry’s progress
towards higher voltages and greater efficiency. Additionally, the traditional
1000 V DC PV disconnects have been expanded to now cover simultaneous switching
of three DC circuits up to 500 amperes.
Allen Austin, Global Solar Industry Manager for ABB’s Low Voltage
Products Division explains that the new product range is part of ABB’s continued
product expansion in advanced design technology including reduced number of
poles, visible blade technology and compact packaging, making for higher
efficiency and power yield in the solar marketplace.
For installations with more than one circuit, OTDC allows control of two
or three circuits simultaneously with only one switch instead of two or three
separate ones.
The current levels in some of the largest main inverters may be higher
than what is nominally covered by the OTDC range. However, with the existing
OTDC switches and ABB connection kits, it is possible to use a tested solution
to create outputs of up to 1500 A (IEC) and 800 A (UL). These higher currents
achieve up to 37 percent more compact space than corresponding products in the
market.
Though most systems reach up to 1000 V DC, one of the trends in the photovoltaic
industry is the evolution towards higher voltages. ABB responds to the demands
of the global market by making available OTDCs for 1500 V DC from 315 to 500 A
(IEC) and from 250 to 400 A (UL). OTDC from 16 to 32 A, which is now available
also for UL508I, has an outstanding thermal performance. The rated currents do
not need derating even beyond 60°C (140°F), making them ideally suited for hot
climates, where OTDC offers reliable performance and energy efficiency.