Cut the Wires, Cut the Cost

Cut the Wires, Cut the Cost

It is easy to understand why a wireless approach to remote monitoring costs less in an industry such as nuclear power, where installation costs are estimated to be as high as $2,000 USD per foot. Fortunately, not all applications have such high installation costs. What about other applications such as remote monitoring, structural health monitoring, or asset protection? How do the costs of wireless and wired compare? The answer depends on the application, but you can conduct a baseline analysis if you assume the following:

•         Software investments are equal

•         The costs of line, solar, or battery power are not included

•         The networking infrastructure to enterprise is the same for wired or wireless implementations

The cost remaining is the actual cost of Ethernet with copper or fiber cables and repeaters compared to the cost of a wireless installation. A review of cable suppliers on the Web shows standard CAT 5 Ethernet cable ranges from $260 to $430 USD for a 1,000 m bulk roll. The specified distance for 100BASE-TX Ethernet is 100 m, so reaching 1,000 m requires 10 repeaters at a cost of $30 USD for each nonindustrial unmanaged repeater. Therefore, a 1,000 m run of copper CAT 5 cable costs about $580 USD. With multimode fiber, 100BASE-FX specifies a distance of up to 400 m at 100 Mbit/s, and a 1,000 m stretch of fiber cable costs about $1,300 USD. Three fiber repeaters are necessary at $150 USD each. In total, 1,000 m of fiber-optic cabling costs $1,800 USD. Figure 1 shows quoted cabling costs and repeaters from various vendors. Cabling costs increase for outdoor CAT 5 cable and weatherproof repeaters.

An overview of the cabling costs in Table 1 shows a range from $580 USD for copper Ethernet cable to $1,800 USD for fiber cabling per 1,000 m. This cost does not include measurement devices or PC or embedded control hardware. Eliminating wires with wireless systems provides a clear cost savings in Ethernet cabling.