Digifoam – Digital fully automatic Around-The-Pump (ATP) foam proportioning system is used to maintain selected constant foam-water proportion regardless of water flow and pressure fluctuations. The system accurately delivers foam concentrate from 0,1 % to 8%.
The system utilizes a brass eductor installed on the discharge side of the fire pump to send a small volume of water back to the suction side of the fire pump. The venturi action of the eductor creates a vacuum at the foam concentrate inlet allowing foam to be pulled through the metering valve, into the water stream. The rich foam solution is discharged back to the suction side of the fire pump and sent through all the discharge piping – allowing foam solution of the required proportion to be available for each discharge outlet.
The backpressure – water pressure entering the pump should always be almost zero, any back pressure on the ATP proportioner could reduce the foam induction rate.
Hydraulic diagram
The DIGIFOAM DF type standardly uses a large 7” TFT LCD unit for overall control of all functions of the system and allows an easy overview of process data, such as water-flow, foam-flow, proportional rate, warning and error messages.
The DIGIFOAM DFL type on the other hand uses a PCU (Pump Control Unit) with an integrated foam management system instead.
Digifoam can be used as a stand-alone system or as a part of the MMX system connected via CAN bus to the other MMX devices. Several remote LCD display control units can be connected to control the foam proportioning on different locations e.g. in the driver’s cabin.
The eductor assembly includes an eductor and a special electric metering valve. The eductor housing and valve are in brass.
Operating Range & eductor assebmly