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Specialists in the field of naval power conversion and distribution, we have our equipment in service on virtually all of the Royal Navy’s submarine and surface fleet.
The chosen supplier for Converted supplies and UPSs for the Royal Navy’s AAW Destroyer the Type 45. We are fully represented on the Queen Elizabeth Class aircraft carriers, the Type 26 destroyer and the Type 31 Frigate.
We have built up a strong export business and our equipment is deployed worldwide from Australia to Malaysia, from Oman to Spain, Turkey and Japan.
We have supplied DC and Helicopter start systems to Australia’s Hobart Class destroyers. UPSs and Battery Chargers for MARS tankers built by Daewoo (DSME) in Korea for the Royal Fleet Auxiliary. Our designs support a number of current European warship programmes including the S-80 submarines built by Navantia at Cartagena in Spain and DCN’s Scorpene Class submarines.
In the normal course of events electrical supply is 115V AC or 440V 3phase generated internally and distributed throughout the vessel. This will support basic functions such as entertainment and domestic lighting through to Command and Control and weapons systems. A recurring theme in our equipment is support of electrical power in emergencies (such as the loss of main ship’s power) and the need to convert that original AC supply either to a higher frequency or to DC.
Our products are ruggedised to meet high levels of shock and vibration, engineered to be fully compatible with ship and submarine electrical systems and are built from the ground up for deployment. Many equipment have been successfully tested to Mil-Std and Def-Stan tests for shock, vibration and EMC.
Below are some product data sheets examples that illustrate the broad range of specifications and applications.
Talk to us and we will be able to assist, call +44 (0)1722 413 060 or, if you prefer get in touch with our Sales Team.
The Automatic changeover switch (ACOS) provide the capability to automatically switch a load between a ‘Normal’ and an ‘Alternative’ supply.
Switching employs mechanically interlocked contactors and is controlled by electronic monitoring of the supply.
Override facilities are provided which allow for manual selection of either power source.
Valve regulated lead acid batteries are used to support ships essential 24VDC supplies. Batteries of various sizes can be selected to meet the user’s required load and autonomy time, typically between 5 and 60 minutes.
The BB range of battery boxes provide a rugged enclosure to house the batteries as well as provide extensive monitoring of the battery system. Typically, the battery box will have meters for voltage and current as well as monitoring circuits for overvoltage, low voltage, excess hydrogen and short circuit cell detection.
The battery boxes are designed for use with one of Gresham Power Electronics TRUs or DC chargers.
The chargers consist of an input automatic changeover switch, an auto transformer, rectifier modules, and output distribution.
The rectifier provides a high quality nominal 24V output at the rated load from a 440V 3phase 60Hz supply. The rectifier uses switched mode rectifier modules configured in parallel to produce the regulated output suitable for charging valve regulated lead acid batteries. In the event of failure of the ship’s normal ac supply, the input will be switched automatically to the emergency supply.
The charger distribution consists of 2pole miniature circuit breakers.
Built into steel enclosures for deck or bulkhead mounting, the chargers are suitable for shock levels up to 15g. Above this shock mounts can be used.
Ingress Protection level is to IP23, suitable for electrical compartments or IP44 suitable for machinery spaces.
The DC chargers can be used as stand-alone DC supplies but are generally used in conjunction with a battery box from the Gresham Power Electronics BB range.
Combined charger/battery and distribution equipment can also be designed to suit specific applications if required.
A DC system typically consists of TRUs (Transformer Rectifier Units), batteries and distribution, either as separate units or combined together dependent on the user requirements.
The TRU can either be from the 3RC range of 12 pulse thyristor rectifiers or the 3RP range of equipment that utilises switch-mode rectifier modules.
Valve regulated lead acid batteries are used to support ships essential DC supplies via output circuit breakers.
Batteries of various sizes can be selected to meet the user’s required load and autonomy time.
The distribution typically consists of output circuit breakers and charger/battery isolators.
Gresham power Electronics also supply Ni-Cd Battery Charger Assemblies for use on submarines. These are combined assemblies or separate chargers and battery boxes. The assemblies have extensive monitoring for alarm and fault conditions.
The Control Unit CU11605 is a control panel dedicated to Fire Door Control.
The 440V 3ø 60 Hz ship’s supply feeds an integral Transformer Rectifier Unit which provides a high quality output of 120 volts dc at 10A. The Control Panel is operated from this 120V dc power source.
A Helicopter Starting/Servicing System typically consists of a Transformer Rectifier unit (TRU), a Static Frequency Converter (SFC), contactor boxes, control panels, socket boxes and cables.
The Transformer Rectifier Units used for shipboard helicopter starting applications have three basic modes of operation:
The Static Frequency Converters supply the helicopter with 200V, 3ph, 400Hz with high overload capability.
Contactors are typically used to control the outputs of the power equipment to the helicopter. They can be incorporated into the power equipment or supplied in separate enclosures.
The Gresham Range of Motor Starters are 440V I/P and O/P with under-voltage and phase rotation protection. They also incorporate trip functions derived from the motor.
The range consists of Direct On Line starters up to 30kW and Closed Transition Star/Delta starters up to 65kW.
Each starter also includes the following features:
The navigation and signal lights are controlled from a panel that fits into a console located on the bridge. This is linked to a power panel located within the console.
The Static Frequency Converters (SFCs) are designed to supply 3phase, 400Hz outputs.
Connected to the ships main 440 volt 3 phase 60Hz supply, the SFCs provide equipment with a low distortion and high stability supply.
Typical Outputs are:
200V line/115Vphase, 3 phase, 4wire, 400Hz
115V,3 phase, 400Hz
Single Phase Output is also available
Power Output is typically from 5 kVA to 100kVA
As required for naval applications the Static Frequency Converters meet the necessary ruggedness requirement in term of shock and vibration and also meet naval EMC requirements.
Gresham Power Electronics have a range of transformers and distribution panels used in ship’s power systems.
The transformers, up to 75kVA, are vacuum impregnated, enveloped for the harsh environment and housed in sturdy steel enclosures. Alternatively, the transformers can be combined into other power converter equipment to give full galvanic isolation to the converted power system.
The distribution panels consist of shock rated circuit breakers mounted in steel enclosures., each circuit breaker is specific to the user requirement and is identified by an individual tally. The circuit breakers can also be assembled into power converter equipment to avoid the need of separate distribution panels for custom built systems.
The Transformer Rectifier Units provide a high quality output of 27.4 volts dc when used for float charging valve regulated lead acid batteries or can be set for 24V for ships 24V systems.
Military Grade Uninterruptible Power Supplies (UPS)
Instant battery support for critical functions if the main power is lost. Emergency power cuts in with no interruption and is available typically for up to 30 minutes.
We supply UPS equipment up to 60kVA for the Type 26 Frigates, the Type 45 Destroyer, MARS tanker support vessel ant the QE Class Aircraft Carriers.
As required for naval applications the UPS meet the necessary ruggedness requirement in term of shock and vibration and also meet naval EMC requirements.
In addition to these main systems Gresham manufactures a wide range of individual support equipment including:
Vessels | Equipment |
| Type 26 Frigates | UPS |
| Queen Elizabeth Class Aircraft Carriers | UPS |
| Type 45 AAW Destroyer | UPS 24VDC Converted Supplies & Distribution Static Frequency Converters Helicopter Starting Rectifiers |
| River Class OPV | Helicopter Starting Rectifiers |
| Astute Class Nuclear Submarines | Inverters Circuit Breaker Protection Modules |
| Trafalgar Class Nuclear Submarines | Inverters Circuit Breaker Protection Modules |
| Vanguard Class Nuclear Submarines | MSC Interface Panel Circuit Breaker Protection Modules |
| Type 23 Frigates | Rectifiers Static Frequency Converters |
| Sandown Class Minehunters | 24VDC Converted Supplies & Distribution Static Frequency Converters |
| Hunt Class Mine hunters | Static Frequency Converters Circuit Breaker Protection Modules |
| LPD Albion Class | Static Frequency Converters Inverters |
| LCVP | Power Supply and Distribution |
Vessels | Equipment |
| MARS Tankers | UPS Battery Chargers, Batteries & DC Distribution |
| RFA Various | Helicopter Starting Rectifiers |
Vessels | Equipment |
| Hobart Class AAW Destroyers | Battery Supported DC System Helicopter Starting Rectifiers Firedoor Rectifiers |
| Huon Class Minehunters | Static Frequency Converters |
| ANZAC Class Frigates | Helicopter Starting Rectifiers |
Vessels | Equipment |
| Type 22 Frigate | Frequency Converters |
| LPH (Ex HMS Ocean) | Inverters Helicopter Starting Rectifiers |
Vessels |
Equipment |
| Ragam Class OPVs | Navigation Light & Signal Panels |
Vessels | Equipment |
| Victoria Class Submarines | Static Frequency Converters |
Vessels | Equipment |
| Scorpene Class Submarines | Battery Charger Assemblies |
| Type 23 Frigates Project Puente | Frequency Converters & Rectifiers |
Vessels | Equipment |
| Sandown Class Minehunters | Static Frequency Converters Rectifiers & DC Distribution |
Vessels | Equipment |
| Roussen Class Fast Attack Craft | Static Frequency Converters 24VDC System UPS Filter Boxes |
Vessels | Equipment |
| Scorpene Class Submarines | Battery Charger Assemblies |
Vessels | Equipment |
| Sugashima Class Minehunters | Static Frequency Converters 2093 SONAR SFC |
Vessels | Equipment |
| Hawk Class Patrol Boats | Static Frequency Converters |
Vessels | Equipment |
| Lerici Class Minehunters | Static Frequency Converters |
Vessels | Equipment |
| Lekiu Class Frigates | Frequency Converters & Rectifiers |
| Scorpene Class Submarines | Battery Charger Assemblies |
Vessels | Equipment |
| ANZAC Frigates | Helicopter Starting Rectifiers |
Vessels | Equipment |
| Fridjof Nansen Class Frigates | Battery Supported DC Distribution Helicopter Starting Rectifiers |
Vessels | Equipment |
| Khareef Class Corvettes | ACOS 24VDC System Helicopter Starting Rectifiers Helicopter Start/Service System Motor Starters Navigation Light & Signal Panels UPS Static Frequency Converters Filter Boxes |
Vessels | Equipment |
| Barzan Class Fast Strike Class |
Vessels | Equipment |
| Al Jawf Class Minehunters |
Vessels | Equipment |
| Emblem Class |
Vessels | Equipment |
| F-100 Alvaro de Bazan Class | Battery Supported DC Distribution Helicopter Starting Rectifiers Firedoor Rectifiers |
| Segura Class Minehunters | Static Frequency Converters |
| S-80 Submarines | Rectifiers & DC Distribution Battery Charger Assemblies |
| Cazaminas – Minehunters |
Vessels | Equipment |
| A Class Minehunters | Static Frequency Converters 2093 SONAR SFC |
With over 80 years designing, manufacturing and supplying power supplies for some of the most demanding applications, Gresham has a strong reputation for service and support.
We offer a wide range of both standard and custom power supplies with many items readily available from stock.
