Tablet-coating operations typically use either aqueous coatings or solvent-based coatings (typically acetone or isopropyl alcohol—both very volatile). While aqueous coatings present no difficulty in packaging beyond NEMA 4X, packaging a computer/display system for solvent-based coatings typically requires an intrinsically safe enclosure rated Class 1, Div. 1 or 2. In Europe, Class 1 Div. 1 is equivalent to ATEX Zone 1. This means that the computing equipment must withstand initial purge pressures and operate continuously under pressure.Finding an Industrial Computer
After investigating several industrial computer manufacturers and their products, Vector settled on CCS-Industrial
’s 21.3 in., Model ICP2100 panel PC. The computer has a NEMA 4X-rated, stainless-steel faceplate and an active-matrix LCD display with 1,600 x 1,200 resolution, a 170° viewing angle, and 250 Nits brightness. CCS provides industrial-grade computer hardware and enclosures, as well as integration, design and engineering services for OEMs and end-users.
Strongarm’s NEMA 4X operator interface pendant and enclosure (602-CW3V02-242412-RH-P9) was mounted to the coating machine. The first system to use the computer/pendant mounting configuration was the company’s Model VPC-1355, which is a medium-sized coating machine. The same configuration is now used on the company’s VPCC-60L fully perforated Containment Tablet Coater for processing potent compounds.
The computer runs two hard drives in RAID 1 format. With support for two 1 Gigabit Ethernet ports, the computer allows connection to the PLC on a private network, and the other network port connects to the user’s plant-wide and enterprise network for data archiving. Configuring network ports on different networks (e.g., 192.168.0.x and 192.168.1.x) significantly cuts back traffic, and reduces bottlenecks on both networks. It also adds a level of security to the process.
Additional slots allow use of PLC interface cards or other peripherals if needed, although Ethernet serves well in most applications. The computer’s CPU is supported by Intel 845GV (Northbridge) and ICH-4 AGPset (Southbridge) chipsets. With a built-in modem and Windows XP Professional’s ability to support remote connections, the company can troubleshoot customer problems worldwide from its Iowa location. For security reasons, such as demon dialers, customers only connect a phone line to the system when troubleshooting is necessary.Implementing the System
Setting up and configuring the computer involved installing prepackaged software, drivers and custom-written software. One change to BIOS was necessary to allow for cycling of ac power off and on. The company installs SCADA software, which is typically GE Fanuc or Wonderware, and sometimes Rockwell Software’s RSView. Customers can choose Siemens or other controllers in place of the SLC 5/05. The company develops and writes its own software package, Recipe Workspace, which connects with most common SCADA and PLC products. Recipe Workspace is an icon-driven batch program that allows engineers to set up recipe programs for different products. Built on the ISA S88.01 State Model, the software includes phases and units within recipe parameters. The computer runs the entire system, collects all the data, logs the data to any database, such as SQL, Oracle or MS Access, and is compatible with FDA regulations.