The heart of the system is a changeable sequence of instructions that control the actions of hoists. Standard instructions include: Move, Lift, Lower, Dwell, Rotate,
Interlock, Plate, and End. We can control 1 and 2 hoist systems with the standard package and 4 hoists with the expanded version.
We use a duel encoder system to control each hoist laterall “Move”. One
encoder is connected to the drive wheels and one connected to the second axel. The encoders are used in a variety of configurations. Typically, one is selected as the lead and the second as the follower. We can monitor the movement to determine problems such as slipping, binding, obstructions, and hardware failures. The “Lift” and “Lower” functions use limit switches or proximity switches to determine Up, Middle, and Down. An encoder can be used for higher
precision when desired.
Hoist Mounted Control[Excalibur]
The control box contains the encoder, power supply, Remote I/O assembly, terminals, and relays. The remote I/O assembly mounted on the hoist takes the manual inputs such as joy stick movement, manual/auto select, and “Auto Center” push button. Outputs include indicator lights for “Manual” and “On Center’. The encoder is protected from the environment through a sealed shaft that connects a belt between the axel and the encoder pulley. The belt reduces vibration and electrical issues.
We greatly reduced the amount of wiring that has to be connected to the hoist. We observed many problems on a plating line that were attributed to the input signals giving false signals due to high voltage noise in the track or festoon. The low voltage encoder signals are isolated in the control box. The trolley and hoist motor control must be brought from the drive panel. The E-stop, power supply voltage and a ground wire must also be contained in the track. We put 2 shielded industrial Ethernet cables in the track isolated from the high
voltage. Siemens has the ability to detect a Ethernet cable problem and reroute the communication to a backup connection. We create a “Ring” rather than a liner topology.
Plating control is essential for making a good part. Many existing systems have a large plating tank with several stations for either racks or barrels. Some newer systems implement individual plating tanks and controls. We have several configurations to fit the customers system. A remote fiberglass panel is used to create the interface. Only the redundant Ethernet, line voltage for the power supply and a ground cable need to be connected.
Analog voltage and ampere values are processed at the remote I/O panel. Alarms and indicators are configured with a variety I/O cards.
Plating Tanks Select
We have the ability to activate/deactivate plating stations on the fly. This is an essential tool when excessive down time can cause a run-away over-plate condition. Servicing the 8th position in a plating tank takes much longer than the 1st position.
We have made it possible to hold the hoist over the 1st position until a timer has expired. This makes the cycle time the same for all positions.
Barrel lines require rotation in the tanks and up on the hoist. We have instructions to begin the barrel rotation and “Dwell” instruction to hold the hoist in place. The
flexibility permits rotation during movement, dip and rotate while still on the hook, and selective tank rotation. Note: The up rotation motor can be controlled locally in the hoist with the addition of a motor starter using the line power brought in for the remote I/O.
The main panel is designed to be mounted at the front of the plating line. We provide terminals to connect the load system with line control. Scales to regulate the load in each barrel can give us an analog value to be used during the process.
“Rack Ready” from a push button will clear the hoist for pick-up in a rack application.
Customers may select to use separate controls for their process needs.
We offer control modules for temperature, PH, and chemical pumps. The hardware needs vary greatly. Temperature input can be thermocouple, RTD, or a process signal from a separate controller. Temperature output can be a 4-20 signal or on/off for a steam valve. PH meters can be quite sophisticated. We can monitor their control and log data for quality control. Chemical pumps are normally configured with a timed wait/active function during line operation.
End of Cycle
When the hoists complete their sequence, they return to a home position.
They wait for all to finish before they begin the next cycle. A master cycle timer is employed to hold the hoist if additional plating time needed.
We have the ability to track and record data on many levels. We can generate reports on cycle times, total weight, chemical usage, fault history, maintenance history.
Barrel specific data is gathered at several points throughout the process. We can log the time and temperature of each bath. The voltage and amperage come from the plating cell, PH and other can be logged as we bring the information to the PLC.
The barrel/rack is given a tag on entry to the process. The data is placed in the “Locker”
during the process. The barrels are tracked through the process. Barrels can be added or eliminated through the HMI if the physical barrel is removed/added. The data is removed from
the “Locker” when the barrel exits the system. The tag again becomes available. The information is stored in a sequential data bank.
The extent of the depth of the interface is constantly increasing. We develop the screens as we grow. We have sections dedicated to Automatic control, Plating Tank, Sequence modification, Alarm/Fault handling, Process control, Data management, Tank encoder positions, and Maintenance.
Drives Panel The drives panel is custom for almost every line. The trolley and hoist motors are connected to variable drive units. Several other motors in the system that run at full speed are controlled by motor starters. The high power creates electrical noise and heat that should be dealt with in a separate enclosure. We mount a remote I/O rack in an existing power panel. We may use a relay to activate an existing starter due to voltage or high amp concerns.
Independent drives may have an enable input, fwd/rev input, analog speed input and drive OK output. New drives would be connected over the Profinet where their full interface is available.
The data can be configured into reports that remain in the PLC but it is preferred to take it away from the line. We can isolate the information on a dedicated computer located in the office.
Firewings has made a 30 year effort to support Siemens built equipment. We make plant visits to work directly at the machine. We have conducted remote support by talking with the local maintenance personnel. We have connected directly with the machines via telephone modem. Now, technology has enabled us to work with the IT people to get access over the internet and Ethernet networks.
The “Engine” is designed in several modules, both hardware and software.
We are able to be flexible to customer wishes by configuring only the control that is needed. We can upgrade the existing control as needs change. Adding temperature controls can be as simple as buying the proper remote hardware drop and getting the proven software loaded and tested.
Revisions that correct or enhance can be downloaded remotely. An option developed for one customer may become available to others. Interfaces to other equipment become drivers that can lead to better control.
Diagnostics are highly important in the plating realm. Extensive diagnostics can mean a high volume of feedback inputs that are not cost effective. Our goal is to keep a technician from needing to connect a laptop to troubleshoot the line problem.
Drive control is an area of continual refinement. We now change speeds of the trolley based on travel distance. The load weight can be used to tune the stopping and acceleration of the trolley. Empty or lightly loaded barrels can be slowed on the down movement to avoid a “floating” barrel situation.
Sequence simulation is very complex. Calculating travel time is weight dependent. Experience and data are necessary to provide an accurate model. We can diagnose barrel conflicts and cycle time issues before they occur in actual production.
Hoists move barrels/racks filled with parts through a series of tanks to apply a protective metallic coating. The typical configuration is a line of tanks with a rail system built over top. The operator removes the finished goods before loading new parts onto the transport rack or into a special plastic barrel. The hoists move on the rails lifting, traversing, and lowering the barrels between the different solutions to prepare them for the plating process. Zinc, nickel, Tin, and other metals are dissolved in a bath where the parts are charged with an electrical current. Time and the strength of the chemistry determine the thickness of the protection.
Plating Technology’s equipment division became Andy’s Siemens customer in 1985. Through the OEM years, Firewings helped to develop the controls to meet customer desires. The plating division focused on highly flexible production lines. Finally, the original “Rack Master” line has just been retired after 26 years.
Automatic Rapid Transfer Hoist Remote [ARTHR]
We will have a main HMI control box and 2 hoist remotes built and ready for install. The main part of the system has been developed over 30 years. We have developed several options in our migration to the latest Siemens platform.
The economy and technology have combined to put us in position to offer a software control “Engine” to the plating industry. The economic downturn eliminated many of the plating equipment builders along with plating companies. We can interface to a variety of existing hoists.
This “Engine” is a group of Siemens software control blocks based on code that has been controlling plating barrel movement since the late 80’s.