Bridging Kepware KEPServerEX, Ethernet, and Legacy DH+ Networks

Industrial Internet of Things (IIoT) platforms, Advanced Analytics engines, Manufacturing Execution Systems (MES), and Enterprise Resource Planning (ERP) tools promise unprecedented insights into plant floor operations. They offer the ability to predict machine failures, optimize energy consumption, eliminate production bottlenecks, and dramatically improve Overall Equipment Effectiveness (OEE).

However, a massive obstacle often stands between a plant manager and these digital transformation benefits: legacy automation infrastructure.

Go into almost any high-output automotive, food and beverage, or chemical processing plant that has been running successfully for over two decades. Beneath the modern facade, you will find incredibly rugged, vintage workhorses: Allen-Bradley SLC 5/04 and PLC-5 controllers. These processors are legendary for their reliability; they simply refuse to die.

But their communication standard—Data Highway Plus (DH+)—is an entirely different story. Developed in the 1980s, DH+ is a token-passing network running at slow speeds (typically $57.6\text{ kbps}$ or $230.4\text{ kbps}$) over blue hose axial cable. It was never designed to handle the high-frequency, heavy data polling required by modern cloud analytics or plant-wide SCADA systems.

Attempting to flood an old DH+ blue hose network with thousands of modern data requests will instantly bottleneck the network, crash communications, drop critical alarms, and actually decrease plant efficiency.
Fortunately, you do not have to endure a multi-million-dollar "rip-and-replace" upgrade of your entire control system to solve this. Instead, you can leverage Kepware’s KEPServerEX combined with modern Ethernet-to-DH+ routing gateways to unleash hidden plant efficiency.