ShorPOWER SPA-II2021-10-26T03:53:41-05:00


Product Brochure

The industry leading ShorPOWER® SPA-II is a state of the art marine frequency converter containing features not available in any other converter on the market. An example of these is proportional load sharing between the two marina shore power cords and the ability to operate into a 100% imbalanced load while maintaining the precise regulation of all the output phases. Built using the latest power semiconductors and ferrite transformers the SPA-II is controlled by an ultra-high speed digital signal processor to create an absolutely pure output sine wave.

Worldwide Power
The SPA-II will automatically connect to any dockside marina power source worldwide and provide clean, stable and reliable marine power supply for the yacht. Fully compatible with all types of marina breakers and complying with shore supply regulations, having an SPA II on board makes the yacht a truly global vessel.

Advanced Power Design
The SPA-II frequency converter utilizes state-of-the-art technology including the latest in power semiconductors and ferrite core transformer technology, all controlled by a ultra-high speed digital signal processing control system to produce an absolutely pure output sine wave.

Reliable Power
The onboard guests do not want to be aggravated by flickering lights, black-outs and generator starts caused by fluctuations in the marina power. Regardless of the dock power quality the SPA-II will always produce stable and reliable power. This reliability is achieved by manufacturing the converter using only the highest quality components and by engineering the converter for actual marine use.

Maximize Marina Shore Power
Many yachts have to reduce their air conditioning and galley loads when in the marina to prevent overloading the circuit breaker on the dock and losing all power. Onboard load imbalance, input power factor and input harmonics can reduce the available power from the marina to the yacht by 35%. The SPA-II converter corrects these problems and allows 100% of the marina power to be available. The SPA-II’s unique dual cord input increases the total available power from the marina since the two cords can be connected to different marina voltages or phases. The load is shared proportionally between the cords based on the marina breaker sizes, this prevents the smaller of the two breakers from tripping early.

Marine Engineered
Designed from the ground up, based on years of marine experience, the converter is packaged in a lightweight aluminum enclosure and is engineered to operate in the worst marine conditions such as high ambient temperature and humidity. It has been extensively tested to ensure that when loads such as large motors and compressors start there are no fluctuations of the output power.


  • Automatically connects to any worldwide marina power system.
  • Works with any RCD / GFCI circuit breaker


  • Balances the current in the input phases regardless of output load imbalance.
  • Conditions the input power to maximize the available power.
  • Available with fully integrated dual shore cord inputs for increased capacity.
  • Shares the current proportionally between the two shore cords to maximize the power obtainable from the dock.
  • Reduced current at start up prevents nuisance trip of marina breaker.


  • Provides protection against marina voltage transients.
  • Output power is stable even when large output loads are applied.
  • Precise output voltage and frequency regulation.
  • Regulation remains precise even with unbalanced loads.
  • Generous overload capability so no need to start generator during peak times.


  • State of the art power semiconductors and ferrite core transformers.
  • Extensive protection and diagnostic system.
  • Network Compatible – Fully integrated Ethernet-based Communication Data Link (CDL) system


  • Seamless power transfer between SPA-II and the generator.
  • Seamless generator to generator transfer using the SPA-II.
  • Parallelable for increased capacity.
  • Color touchscreen remote control panel.
  • Alternate enclosures available including a modular configuration.
Onboard ShorPOWER Converters
Unit Power Ratings12kVA - 25kVA60kVA - 90kVA37.5kVA - 125kVA
System Power Ratings120kVA - 720kVA75kVA to 1000kVA
Input Voltage187V - 260V177V - 528V177V - 528V
Alternate Input Voltage350V - 528V
Input Phase1 and 31 and 31 and 3
Output Voltage208V - 480V110V - 480V220V - 480V
Output Phase1 or 31 or 31 or 3
Frequency Conversion
Voltage Regulation
Surge Protection
Modular Enclosure
Extended Operating Temperature
Extended Overload
Dual Shore Cord Input
Seamless Transfer
Communications Data Link
Onboard ShorPOWER Converters for Larger Yachts
 SPA-IISHFUltra HFUltra HPUltra HV
Unit Power Ratings60kVA - 90kVA37.5kVA - 125kVA20kVA - 125kVA150kVA - 1.6MVA100kVA - 125kVA
System Power Ratings120kVA - 720kVA75kVA to 1000kVA
40kVA - 1000kVA300kVA - 1.6MVA200kVA - 900kVA
Input Voltage177V - 528V177V - 528V177V - 528V177V - 528V350V - 528V
Alternate Input Voltage
Input Phase1 and 31 and 31 and 333
Output Voltage110V - 480V208V - 480V220V - 480V380V - 480V220V - 480V
Output Phase1 or 31 or 31 or 333
Frequency Conversion
Voltage Regulation
Surge Protection
Modular Enclosure
Extended Operating Temperature
Extended Overload
Dual Shore Cord Input
Seamless Transfer
Communications Data Link


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