Eaton’s Carter brand Model 60554 hydrant valve was developed to be used with a pressure control coupler. This revolutionary design removed many of the complicated control devices previously located in the pit, thereby reducing the cost of hydrant systems dramatically.
Eaton’s Carter® brand hydrant valves (Models 60554 & 61654) are now also available with a new line of
“remote” pilot options. These patented designs take the concept one step further by removing the pilots from the Hydrant Valve and replacing it with a sealed male disconnect fitting. As a result you only need to have one pilot for each hydrant …

Automatic Calculation of Corrected Differential Pressure for Varying Flow Rates
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The Problem with Water Detector Probes has always been that they are impossible to test periodically without injecting water into the vessel. People have been afraid that too much water may be injected. The One-CC Probe solves this simply. First, it has a new, unique design (patent applied for) that only needs 1 ml (1cc) of water for a complete test. Second, it has a built-in water pump, and this pump is only capable of injecting 1 ml (1 cc) of water.