The Fairchild T7900 series Electro-Pneumatic Transducers include the Fairchild T7900 with Analogue Output and the Fairchild T7900D with DeviceNet™ Communication.
The Fairchild T7900 controls pressure in proportion to an analogue electrical input signal. An internal feedback sensor monitors output pressure to achieve high accuracy.
The Fairchild T7900D Transducer with DeviceNet™ Communications controls output pressure in response to a digital communication command.
The Fairchild T7900 Series Transducers have a closed-loop, integrated, microprocessor control system that regulates outlet pressure. You can control the output from the Fairchild T7900 using the keypad or from an analog control signal. You can control the output from the Fairchild T7900D using the keypad and through DeviceNet™ Communication network.
The Feed and Bleed Solenoid Valves control pressure in the Signal Chamber of the Booster Section. A pressure sensor measures the outlet pressure and provides a feedback signal to the Electronics Section. Any variation in pressure between the setpoint and the outlet pressure activates the Feed and Bleed Solenoid Valves to change the output pressure.
200 psig, [14 BAR], (1400 kPa) Maximum
4-20 mA, 0-10 VDC
Flow Rate (SCFM)
100 (170 m³/HR) @ 100 psig, [7 BAR], (700 kPa) supply @ 20 psig, [1.5 BAR], (150 kPa) setpoint
Exhaust Flow (SCFM)
50 (85 m³/HR) @ 60 psig, [4 BAR], (350 kPa) d ownstream pressure @ 5 psig, [.35 BAR], (35 kPa) above setpoint
0 @ steady state output with Deadband @ 1 % of Full Scale
Supply Pressure Effect
No Measurable Effect
24 VDC ± 10 %
Less than 5 watts
Analog Output Signal / Impedence
4-20 mA/500 ohms Maximum, 0-10 VDC/400 ohms Minimum
Deadband (ISA S51.1)
Adjustable from 0 to 10 % of Full Scale
Unit Accuracy (ISA S51.1)
Less than 0.50% Output Span
-3 db @ 1 HZ per ISA S188.8.131.52 load Configuration A
Less than 1 % of Span under the following conditions: 5 - 15 Hz @ 0.8 inches constant displacement 15-500 Hz @ 10 g’s
Less than 0.5%. EMC Directive 89/336/EEC European Norms EN 50081-2 & EN 50082-2.
0°F to + 160°F, (-18°C to + 71°C)
Materials of Construction
Body and Housing: Chromate Treated Aluminum
Cover and Pintle: Acetel Plastic
Trim: Zinc Plated Steel
Elastomers: Fluorocarbon and Silicone
1Supply Pressure must be no less than 5 psig, [0.35 BAR], (35 kPa) above maximum output.