SCR Training Course ProgramDay 1
Basics of Rectification – Diode Operation, Testing a Diode, Single Phase Bridge, Three Phase SCR bridge, SCR Rectification, Testing an SCR, SCR Failure Modes, SCR Protection (snubbers)
SCR DC Motor Control – DC Motors, Voltage Feedback, Current Feedback, Control Loops, DC Module Electronics
Day 2
Generators – Exciter Control, Actuator Control, AC Module Electronics
Practical – ‘Oscilloscope Training’ and ‘Module testing using Oscilloscope’
Day 3
SCR System Logic – Assignment, SCR Control Circuits, Logic Indicators, Purge Cycles and Remote Auxiliaries, Troubleshooting, Passive Field Supply, Active Field Supply, Mud Pump Active Load Sharing
Practical – ‘Changing a Thyristor Puck’ and ‘Using a fault finding simulator’
Day 4
SCR System Circuits – Power Limit, Driller’s Console, Sprocket Slip, AC Ground Fault Detection, DC Ground Fault Detection, Dynamic Braking, Regenerative Braking, Surge Suppression, Schematic Drawings
Q&A Session
To learn more about the training courses, please click here
AC & DC Control Modules
Leveraging our proprietary database of Hill Graham and Ross Hill modules and their history, Zeefax can supply exact parts or provide suitable replacements for your legacy modules and systems.
Combining this with the vast experience and expertise of our technicians (most of whom are former Hill Graham employees in the UK), we can supply or re-engineer individual modules and components as necessary, and can often improve on the original specification and functionality of AC and DC control modules.
An important aspect of this service is that where an exact replacement is not available, either due to limited supply or component obsolescence, Zeefax can engineer a replacement part which will have the exact same footprint and electrical connection points as the original. This means that equipment manufactured 30 or more years ago, is still fully supported by Zeefax and can continue to be used to provide a return on investment well beyond the normal life expectancy.
New Digital Modules from Zeefax
We are uniquely positioned to provide replacement AutoSync modules for Hill Graham and Ross Hill type systems.
In order to take advantage of modern components and manufacturing techniques, and to enhance the original design, we have fully re-designed and re-engineered the AutoSync module.
It is vital for new products and systems to remain compatible with existing legacy systems, and although this product is fully digital, it is an exact replacement occupying the same footprint and the same pin configurations as the traditional analog module.
This important fact ensures that for those users wishing to upgrade their control systems, but wish to retain existing wiring and connections, the upgrade path remains easy and cost effective.
Re-engineered Controls Systems
After years of reliable service, many Hill Graham Controls (HGC) and Ross Hill Controls (RHC) systems remain serviceable even though parts have become obsolete or repairable. Following our acquisition of Hill Graham Controls, Zeefax is now able to fully support legacy systems, and can provide alternative solutions by identifying and sourcing equivalent parts for obsolete items, or by providing completely re-engineered products.
Additional Generating Capacity
Where additional generating capacity is required, we can conduct a detailed study and examine the feasibility of upgrading a system and follow that up with a modification and manufacturing program to complete the job.
Modern drilling practices often demand additional features or functionality which was not originally envisioned in older systems – for example, additional mud pumping capabilities are often required in modern installations. To that end, Zeefax can revitalise a rig by adding additional capability, such as a third Mud Pump with the associated add-on mini console.
Minimising Cost and Disruption
Add-on systems from Zeefax are carefully considered and designed to match closely with the existing legacy system, thereby minimising disruption and upgrade costs.
The result of this is that rigs and marine vessels which depend on these parts have a new and extended lease of life – often with a significant saving on the alternative solution.
Comprehensive design and Build from Zeefax
Motor and drilling control systems can be supplied fully integrated into transportable, skid-based, air-conditioned houses or enclosures, or we can supply engineered kits of parts for installation into existing cabins or enclosures for ultimate flexibility.
These rugged packages, manufactured entirely in the UK, are built to withstand the rigors of transportation over rough terrain and harsh environments.
In line with recent trends in Offshore systems, Zeefax is able to offer AC drilling drives as well as the traditional SCR (DC) based systems. We specialise in servicing and upgrading legacy systems of Hill Graham Controls (HGC) & Ross Hill Controls (RHC) types, including life extensions.
Zeefax can provide a ‘Total Power Solution’ for upgrading and refurbishing existing legacy systems, which represents significant cost saving compared to the cost and production of replacing an entire system. Our experience and extensive stock of hard-to-find parts means that we can upgrade and replace only as necessary to preserve the operation and reliability of the system whilst leaving the remainder intact.
For new installations, we can provide systems with switchboard power ratings of up to 6000A (600V) and 100kA fault rating, and with class approvals from ABS, Lloyds, DNV, Rina, Germanischer Lloyd, Canadian Coastguard and other authorities – our customers can be confident of operational reliability and construction quality.
To see a selection of our system case studies, please click here Case Studies.
Easy Upgrades
The new module is identical in fit, form and function to the legacy Hill Graham Controls DDC module, and importantly, the wiring harness connection points are also identical, making upgrading and replacement simple and quick. For new build systems, it provides complete control and protection for operation of a DC drive and the associated motor.
Features
- All new digital control for DC Motors
The DDC module possesses an identical footprint to old style legacy DDC modules, making upgrading simple and quick.
The Full Colour LCD touch screen provides a series of display formats which can be used to display all of the key motor parameters. It also includes parameter tuning, enabling the DDC to be matched to a wide range of drive / motor combinations.
Digital Speed regulator automatically adjusts the armature speed by comparing the measured speed feedback with the required speed reference. The output Torque command ensures that the speed is constant, even during load changes, and the control algorithms can accommodate both Field Weakening and Load Sharing situations.
The armature current is regulated by the Armature Rectifier Board, which adjusts the armature firing reference angle (alpha angle) to maintain constant rotational speed.
The field current is controlled by the Field Rectifier Board. It is a pre-set reference value which is usually fixed. If required by the application, Field Weakening may be used in Tandem or Load sharing installations.
Automatic reversal using 4-Quadrant control of the DC Motor.
- Motor and Drive Protection features
A comprehensive array of motor and drive protections, including Current Limiting, Over Current Trip, Over Speed trip, Input Supply Loss, Power Limit, Field Loss and other user defined protections, such as Cooling System Alerts, Lube Oil Temps and Motor Winding Temps etc.
Field Service and SCR System Support
Our wealth of engineering experience, combined with a well-trained, highly skilled and motivated multi-disciplined workforce, means that Zeefax is uniquely positioned for all electro-mechanical projects, targeted mainly at the Drilling and associated sectors.
Based at our fully equipped manufacturing facility near London, we maintain a well trained and highly motivated team of field service engineers (ex Hill Graham Controls), ready to support you in all your your service needs, including emergency call outs for rig shutdowns as well as with troubleshooting and SCR maintenance programs.
Zeefax is able to service most SCR and VFD drives, particularly Hill Graham Controls (HGC) and other types including Ross Hill Controls (RHC), IPS and GE Micro Drill systems. We can also provide a wide range of support services, including system start up and commissioning, as well as regular SCR health checks, in order to ensure that your systems remain operational and available, and to avoid unexpected shutdowns or downtime.
Keep legacy system Operational
Many legacy SCR systems from Hill Graham Controls (HGC), or other manufacturers including Ross Hill, installed in the 1970s and 1980s, remain serviceable even though parts may have become obsolete or unrepairable.
As part of our acquisition of the Hill Graham Controls business, we also acquired significant quantities of components and boards which will allow us to keep legacy SCR systems fully operational.
Using our extensive experience and comprehensive proprietary database, Zeefax is able to provide original parts, as well as propose alternative solutions by identifying and sourcing suitable equivalents.
The result of this is that systems which depend on these parts have a new lease of life – an significant saving on the alternative solution, i.e. scrapping the existing generator control sections and completely re-fitting!
Zeefax Power Control Systems are complete and fully integrated, and are optimised for Drilling operations.
Systems typically combine generator and motor control, using AC and DC motor drive technology, and the very latest in top-side control and instrumentation.
Systems can be built based on the long-standing proven technology of the established Hill Graham Controls (HGC) / Ross Hill Controls (RHC) model, or we can provide hybrid designs, providing the best of both solutions, by incorporating modern digital technologies for state-of-the-art control systems.
Traditional Hill Graham Controls / Ross Hill Controls systems are widely used in Land Rigs, Offshore Drilling Platforms, Semi-submersibles, Jack-ups and Drill Ships, and Zeefax is able to provide a complete range of support and maintenance services, extending the life, availability and utility in a cost effective way.
Whether new build or refurbishment of existing equipment, Zeefax has the expertise and flexibility to provide best-fit engineering solutions and back them up with comprehensive after-sales support and training.
Read more about SCR Training Simulator – click here
Maintenance Contracts
Zeefax is pleased to be able to offer maintenance contracts to our customers, with access to telephone, email and hands-on support. Contracted customers enjoy priority support and discounts on services such as field service, spares parts and repairs.
Our maintenance programs begin with complete system appraisals, including documentation and spare parts inventory audits, followed by regular planned maintenance visits.
For customers with multiple systems from a common manufacturer, we can help cut spare holding costs by maintaining a central spares inventory.
Call +44 20 8748 7808 now to discuss further, or email support@zeefax.com
Repair and Calibration
Zeefax has the technical expertise and equipment to repair and re-calibrate the complete range of Hill Graham Controls (HGC) and other manufacturer’s systems including all GE and Ross Hill Controls (RHC) type control modules and printed circuit boards (PCBs).
From our UK-based test facility, we provide a fast turnaround, and have the depth of knowledge and expertise to re-engineer obsolete boards and components to help maintain continued return on investment, and to keep legacy equipment fully serviceable.
Zeefax provides a range of courses covering SCR operation and maintenance and PLC programming and use. These courses are intended for rig electricians and maintenance persons who may have little knowledge of SCR systems, but they are also equally useful for experienced engineers who require an update to their knowledge and understanding of the technology.
Each course can be can be individually tailored to suit the rig type and the level of expertise of the trainees, and topics covered include generator start-up and synchronising, SCR troubleshooting, power limit calibration, theory of operation, PLC controllers, electrical safety, using an oscilloscope for fault-finding.
Training courses are usually held on our training centre, located in Bracknell, England, but can be conducted at your premises if facilities and resources permit.
SCR Training Courses
We provide two levels of training – for novice users and for more experienced users. Courses are tailored to suit the technical expertise of the attendees; a course for technicians with little or no knowledge of SCR systems covers many of the subjects that a more experienced engineer will attend, but in the latter case, subjects are covered in greater depth.
Click here to view the SCR Training Course Program or the menu opposite to view a typical 4-day program.
PLC Training Courses
More and more SCR systems now use PLC controllers for logic control and diagnostics. Zeefax have a specially tailored course to introduce engineers and technicians to PLC controllers including fault finding, basic diagnostics and elementary programming. Training is based around the three most common makes of PLC used on rigs: Siemens, Allen-Bradley and GE Fanuc.
PLC training courses can be conducted separately or as part of a general SCR course. Click here for more details, or the menu opposite.
For more information on Zeefax training contact training@zeefax.com or call +44 (0)20 8748 7808
Spare Parts
We are able to identify and supply Hill Graham (HGC) and Ross Hill (RHC) parts from their original part number, and can provide suitable replacements for parts which have become obsolete.
Using our unique parts database, we can supply exact parts or replacements for your Hill Graham or Ross Hill systems.
Through our in-house R&D, Zeefax is developing improved specification products as pin-for-pin replacements for legacy Hill Graham and Ross Hill type technology.
Advancements in technology mean that many of the power semi-conductors which were built in SCR systems 30 years ago, have been superseded by devices with better specifications.
Zeefax can repair and calibrate AC and DC control modules and PCBs from Hill Graham and Ross Hill including Power Limit, Field Supply Regulator, Sprocket Slip, Drillers Console, DC Auxiliary, SCR Auxiliary and Generator Exciter PCBs.
Servicing the Drilling Industry
Zeefax Limited has been servicing the Drilling industry for almost four decades and is now the only remaining British manufacturer of SCR Systems, as well as DC and AC drive Power Control Systems for both off-shore and land based drilling rigs, platforms, and marine vessels.
Our team of Product Development and Field Service Engineers own an extensive knowledge base of information and specification for the current fleet of Hill Graham Controls (HGC) systems around the world, as well as Ross Hill Controls (RHC) systems, and we are able to provide a complete service of maintenance and support including:-
- Supply of all printed circuit boards (PCBs), components and spare parts
- Supply and Repair of all AC and DC Control Modules, and PCBs
- Supply and Repair of all Marine DC Modules
- Manufacture and Supply of new digital AC AutoSync Modules
- Manufacture and Supply of new digital DDC Modules
- Repair and service of Hill Graham DDC and DFC modules
- Engineered solutions to complex drilling issues
For all Hill Graham products and manufactured components, Zeefax is the Worldwide supplier, and provides a host of other Drilling services including:-
- Field Service Engineering, Maintenance and Troubleshooting
- SCR System Upgrades and Refurbishments
- New build SCR systems – DC and VFD Systems
- Marine DC – Propulsion and Pumping – Repair and Calibrate
- Repair and supply of all AC and DC Modules
- Repair of EGIII – Advanced AutoSync Module
- AF (Adjustable Frequency) – Variable Speed AC Drive – Repair and Refurbishing (new Power Supply)
- Supply of all original spare parts and PCBs
- GE752 Motor Refurbishments
- SCR and PLC Training Courses for Electrical Engineers
