OMEGA® FMA-7000E Mass Flow Controllers accurately measure gases on the basis of mass flow. The flow sensor produces an electrical output signal linear with the flowrate used for indicating, recording, and/or control purposes. It eliminates the need for continuous monitoring and readjustment of gas pressures to provide a stable gas flow. This is accomplished automatically by an electromagnetically actuated flowrate control valve.
OPERATING PRINCIPLE The operating principle of the controller is thermodynamic. A precision power supply directs heat to the midpoint of the sensor tube carrying the flow. On the same tube, equidistant upstream and downstream of the heat input, are resistance temperature measuring elements. With no flow, the heat reaching each temperature element is equal. With increasing flow, the flow stream carries heat away from the upstream element, and carries it towards the downstream element. An increasing temperature difference develops between the two elements and this difference is proportional to the mass flowrate of the gas. A bridge circuit interprets the temperature difference and an amplifier provides the output to the control circuitry as well as a 0-5 Vdc output signal.
SPECIFICATIONS Accuracy: ±1% FS including linearity at calibration conditions, ±1.5% FS including linearity for flow ranges greater than 20 SLM Repeatability: ±0.25% of rate Response Time: <3 second response to within 2% FS final value with a 0 to 100% command step Set Point Input: 0 to 5 Vdc or 1000Ω potentiometer Output: 0 to 5 Vdc into 2000Ω minimum load; 3 mV rms max. ripple Maximum Pressure: 1500 psig, pressure drop 5 to 50 psid Temperature Range: 4 to 66°C(40 to 150°F) ambient and gas Temp. Sensitivity: Zero: < ±0.075% FS per °C Span: <±1.0% FS shift over 10 to 50°C (50 to 122°F) range Power SupplySensitivity: ±0.09% FS per % power supply voltage variation Mounting Attitude Sensitivity: ±0.5% maximum FS deviation after zeroing Leak Integrity: 1 x 10-9 Atm. scc/sec helium Control Range: 50 to 1 Pressure Sensitivity: ±0.03% per psi up to 200 psig (N2) Power: +15 Vdc at 35 mA DC, -15 Vdc at 180 mA dc, 3.5 watts power consumption Wetted Parts: 316 and 430SS, FKM Connections: ¼" stainless steel compression fittings Electrical Connections: Card edge, 20 terminals, gold over low stress nickel-plated copper Accessories Included: Mating connector with 1.5 m (5') ribbon cable model. Easy connector/cable assemblies available
† All dollar amounts on this site are shown in US currency.
Note: Comes complete with mating connector and operator's manual.
Calibrations done at ambient temperature only 20C(70F).
*Please specifiy gas, inlet, and outlet pressure when ordering.
For calibrations between 201 and 999 psig add $400 to price.
For calibrations between 1000 and 1500 psig add $475 to price.
For NIST certificate add suffix "-NIST" to model number, add $425 to price. NIST certificate does not include points.
All models are custom, consult specification page for a complete product description and list of available models.
