The Series EPT-1 incorporates a quiet low-wattage poppet valve and pressure sensor to measure and adjust the branch line pressure proportional to the input. This unit has no air consumption and is immune to mounting orientation and supply line pressure fluctuations. The EPT-1M1 and EPT-1M2 incorporate a manual override switch, and in the manual mode, the pressure can be increased or decreased with two pushbutton switches. This feature is most desirable for check out/commissioning and manual operation in case of controller failure. Universal 24 VAC/24 VDC supply voltage and field selectable 4 to 20 mA, 0 to 5 VDC, or 0 to 10 VDC inputs ensure single unit compatibility with most systems. The unique steel chassis design substantially reduces the overall size of the unit and, at the same time, provides for ease of installation in a control panel directly or with a snap track. A precision gage is provided for the branch line pressure. A rugged aluminum manifold, brass barb fittings, floating poppet solenoid valve, silicon pressure sensor, and high performance electronics are some of the features which make the Series EPT-1 the most reliable electro-pneumatic transducer in the industry.