PCM120AS SCR/VFD Electrical Upgrade
JC’s Marine Power & Distribution’s engineering department along with Emerson Industrial Automation Engineering group are pleased to offer a complete and affordable upgrade to one of the strongest and most reliable Letourneau cranes ever built. These cranes have been working on Letourneau drilling rigs, drill ships and port cranes for decades. The technology used at the time of their entrance to the market was unsurpassed in the electrical industry.
The new ABS type approved electrical upgrade replaces all electrical components excluding the hook, swing and boom motor. The upgrade can be installed on an operating drilling rig with only a 4 to 5 days crane downtime. During this downtime, our team will remove all electrical components, wire, lights and distribution panels. The motors will be left in place along with all motor brakes set for personal and mechanical safety. After initial removal operation is complete, the rig crew can repair, clean and paint the inside as needed. Once the rig crew is complete, our team will then install the new system along with all new electrical components. The heart of the new system includes:
- 1 ea. Hook/Swing DC control cabinet
- 1 ea. Boom VFD control cabinet
- 2 ea. Series field supply controllers
- 1 ea. Externally mounted stainless steel boom resistor bank
All of these components have been specifically designed to fit in the crane through the existing ventilation hole in the bottom of the crane. After all components are mounted and secured in their locations, the team will then install new cable tray and re-wire the system. Once the system is complete, the crane will be powered up and testing will begin along with the training of operators and electricians on system operations and maintenance. After training, a load test can then be performed as needed by company representative.
THIS NEW PCM120AS UPGRADE ELECTRICAL UPGRADE WILL CONSIST OF:
1 ea. Hook Motor Drive System:
• Mentor-MP Digital DC Drive (regenerative)
• Model MP420 A4R rated 420 amps continuous
• AC Line Fusing
• AC Line Reactor
• Steering Bridge Circuitry for series field mounted in NEMA 3R cabinet
• Control Power Contactor
• Motor terminal blocks
• Brake interface circuitry including contactor
• Torque proving logic for auto brake release
• Control terminals taken out to din rail mounted terminal strip
• Required feedback from motor
• Encoder with Quadrature output
• 2 ea. Air conditioners for cabinet atmosphere control
1 ea. Swing Motor Drive System:
• Mentor-MP Digital DC Drive (regenerative)
• Model MP210 A4R rated 210 amps continuous
• AC Line Fusing
• AC Line Reactor
• Steering Bridge Circuitry for series field mounted in NEMA 3R cabinet
• Motor terminal blocks
• Brake interface circuitry including contactor
• Torque proving logic for auto brake release
• Control terminals taken out to din rail mounted terminal strip
1 ea. Boom Motor Drive System:
• Model SP5402 VFD Uni-drive rated 210 amps continuous
• AC Line Fusing
• AC Line Reactor
• AC Output Load Reactor
• Motor terminal blocks
• Brake interface circuitry
• Torque proving logic for auto brake release
• Control terminals taken out to din rail mounted terminal strip
• 1 ea. 15 KW Stainless steel resistor for boom
• 1 ea. Boom drive system Nema 3R custom cabinet
• 2 ea. Air conditioners for cabinet atmosphere control
1 ea. Standard Operator Control:
• 1 ea. Boom/Swing control joystick
• 1 ea. Hook control joystick
• 1 ea. Emergency stop button
• 3 ea. Brake switches
• 2 ea. Power switches
• 1 ea. Drive power and reset switch
• 1 ea. Limit switch alarm lights
Materials and Equipment Needed for Installation:
• 1 ea. Ethernet switch
• 1 ea. Lot mounting hardware and cabling
• 1 ea. Lot power and control cable
• 1 ea. Lot all mounting hardware, including all cable tray
• 1 ea. 480 vac. Cutler Hammer 18 space breaker panel
• 1 ea. 120 vac. Cutler Hammer 12 space lighting panel
• 1 ea. Mounting hardware including terminal strip
• 3 ea. XP limit switches
• 1 ea. Hook motor fan blower
• 2 ea. White fluorescent cab lights
Before PCM 120 Upgrade
Four Leaf Switch
Swing Board
Three Leaf Switch & Hook Board
After PCM 120 Upgrade
Standard Crane Controls
Drive Termination
Hook/Swing D.C. Drives with A/C Units
(replaces hook swing boards)
Steering Bridges
(replaces four leaf switch)
Boom VFD with A/C Unit
PCM120AS ELECTRICAL UPGRADE CUSTOMER TESTIMONIALS
I’ve been operating with the new system for twelve months and have not had one issue. The controls are user-friendly and it allows me to have complete control over all operations of the crane at all times since the hook, swing and boom are combined into two joysticks. The controls are very smooth and have a wide variable speed in hook, swing and boom. In my opinion the boom is the biggest operating improvement with its variable speed you can ease into boom and keep your load stable and your personnel on deck safe. The crane is also much quieter without the MG’s running; you can hear what the crane is doing and what’s going on around you. I’ve also noticed if you’re in a position where you cannot see your hook you can actually hear the hook motor running and know how fast you’re hook is traveling. I can simultaneously hook, swing and boom and safely maneuver loads around personnel on deck where this could not be safely done with the old system. I highly recommend this system; it’s safer, smoother, quieter and virtually maintenance-free.
The new crane system gives the crane a better parameter of operation and is more responsive. Better control to the point where you can perform precision work with the crane. The control panel is simple but efficient. It is my professional opinion that these modifications overall have expanded the scope of operation. I have operated these cranes both before and after the modifications. Most importantly these changes have made a much safer work environment.
DESCRIPTION OF MAJOR COMPONENTS FOR PCM120AS ELECTRICAL UPGRADE
Cutler Hammer 480 VAC Distribution Panel
This Nema 3R Panel has been relocated in crane above swing motor. It contains all power breakers needed along with auxiliary devices for powering new drive system.
Cutler Hammer 120-240 Distribution Panel
This new panel is located in the same location as the original. It contains all breakers needed to supply control voltage, power to the hook motor blower, lighting, and air conditioning system for the hook swing cabinet and Boom VFD cabinet.
15 KVA 480 to 120/240 Control Transformer
This transformer is a dry type that supplies the 120/240 distribution panel for all low voltage needs.
Hook Motor Cooling Blower
This 120/240 blower helps in keeping the hook motor cool during extended use operations.
Hook/ Swing DC Motor Control Cabinet
The new NEMA 3R rated hook/swing cabinets has been designed to fit through the existing hole in the bottom of the crane. The panel is installed where the old Swing MG Set and the 480VAC distribution panel was located. All power and controls are now routed through the top of the panel. When panel doors are open, all hook power and controls are on the left hand side. Swing power and controls are located on the right. Both Air conditioners are mounted on the right side and are set with a 10-degree differential. These A/C units also act as a dehumidifier. The A/C blowers run continuously. The A/C compressor will cycle on and off as temperature requires. The layout of the panel has been designed with an electrician in mind for maintenance and troubleshooting the system, if required. The main cabinet has an Ethernet switch connected to all systems in crane so that the system can be troubleshot from anywhere in the world with the help of a JC’s Marine tech if needed. The Emerson 420 Amp Hook and 210 Amp swing DC drives are sized for twice the normal power needed to run system. We feel that by doing this, the system is never running at its maximum capacity.
Boom Variable Frequency Drive Cabinet
The boom Variable frequency drive cabinet has been designed with all the same features as the hook/swing cabinet. The Boom cabinet is installed where the hook MG was mounted. The main component in the boom cabinet is a 210 Amp Emerson VFD drive. This drive is also sized for twice the normal power needed to operate the boom.
Steering Bridge for Series Field
These 2 components are mounted in separate NEMA 3R cabinets. They are mounted on the wall above the access hole in the bottom of the crane. These components take the place of the old 4-leaf switched that were used to reverse the hook and swing motors. The steering bridge controls the field in only one direction. This allows the Emerson DC Drive to control the direction of the motor. All of this is done by solid state circuitry instead of exposed electrical and mechanical contactors.
Stainless Steel Resistor Bank
The resistor bank is mounted on top of the crane and is used to dissipate energy from boom when going down. By doing this, we keep excess heat on the outside of the crane and away from personnel.
Standard Control Panel
The control panel has been designed so that the addition of a separate operator control station can easily be installed and can be used by changing a single switch. The panel uses pistol grip controls. One control operates the hook with a failsafe trigger. The other control is a four quadrant joystick that controls both swing and boom. This also has a failsafe trigger that shuts control power off, if hand is removed. The other features included in the control panel are an E-stop, boom/hook, swing ready lights, boom, hook/swing limit lights, boom and hook brake switch, swing brake switch, along with control power and location control switches. This panel gives the operator a better overview of operations and control of the crane. All new components are mounted inside cabinets that leave no exposed electrical components which greatly reduces the risk of electrical shock and hazards. This system was designed with personnel safety in mind for both operation and maintenance. The climate controlled cabinets will reduce down time to a fraction of the past for the PCM 120 crane. The system will also allow for technical upgrades that are specific to each client’s needs.