That depends on several factors, including what applications the network supports, the diversity factor (the percentage of open ports at any given time), and the size of the pump specified. With regard to the applications which the network will support, some applications place a high flow demand on the network while others impose a relatively low aggregate flow demand. For example, vacuum drying ovens tend to impose a high demand on the network whereas filtration and rotary evaporation impose lower flow demands (when done properly). Similarly, a low diversity factor means that many ports are closed, and thus imposing no demand on the network pump; this allows for a relatively high number of valves to be installed on a single network. In contrast, as the diversity factor approaches 100% – fewer valves can be installed on a network with high simultaneous utilization. In addition, the size of the pump itself has a large influence on the number of ports that are installed on a network. We offer a wide range of pumps so we can accommodate anywhere from 4 to 25 active vacuum ports. Talk with us about the intended use of your networks, and we can advise you how to ensure that you have sufficient vacuum for your needs without overbuilding.