FMA2600-FVL2600-Series

Supported Applications

The Omega FMA-2600/FVL-2600 Series comprises mass and volumetric gas flow controllers designed for clean gases. These instruments utilize differential pressure across an internal laminar flow element (LFE) to determine volumetric flow, applying the Poiseuille equation while using separate absolute temperature and pressure sensors to correct rates to standard conditions. The series supports 130+ gas calibrations including pure and mixed gases, with capability for custom live gas blend programming storing up to 20 user-defined blends.

Operating Conditions & Performance

The FMA-2600A Series operates within an ambient temperature range of -10 to 50°C (14 to 122°F) and a humidity rating of 0 to 100% RH, non-condensing. Accuracy is specified as ±(0.8% of reading + 0.2%FS), with repeatability at ±0.2% FS and a turndown ratio of 200:1. Control response time is 100 ms (50 to 100 ms typical). The maximum pressure rating is 145 psig; for volumetric mode operation near atmosphere, the recommended maximum operating pressure is 15 psig.

Minimum differential pressure requirements vary by range: 5 SLM and under requires 5 psid; 10 to 250 SLM requires 15 psid; 500 SLM requires 5 psid; and 1500 SLM requires 10 psid. Zero shift is specified as 0.02%/ATM FS/°C, with span shift at 0.02%/ATM FS/°C.

Measurement Ranges

The series covers full scale ranges from 0.5 SCCM to 3000 SLM. Specific per-model full scales include:

• SCCM: 0.5, 1, 2, 5, 10, 20, 50, 100, 200, 500
• SLM: 1, 2, 5, 10, 20, 50, 100, 250, 500, 1000, 2000, 3000

Configuration Options

The series offers configurable output signals and communication protocols. Standard outputs include 0 to 5 Vdc and RS232 communications (RS485 is optional). Optional analog configurations provide 4 to 20 mA, two 4 to 20 mA outputs (-I2), or two 0 to 5 V outputs (-V2). An optional 4 to 20 mA input (-IN) replaces the standard 0 to 5 Vdc control signal.

Process Connections and Wetted Materials

Process connections vary by flow range:

• 10-32 thread: 0.5 to 50 SCCM models
• 1/8 FNPT: 100 SCCM to 20 SLM models
• 1/4 FNPT: 50 to 100 SLM models
• 1/2 FNPT: 250 SLM model
• 3/4 FNPT: 500 to 2000 SLM models
• 1-1/4 FNPT: 3000 SLM model

Models with the positive shut-off valve option (-P) feature 1/4" welded male VCR fittings. Wetted materials include 303 and 302 SS, FKM, heat cured silicone RTV (rubber), glass-reinforced PPS, heat cured epoxy, aluminum, gold, silicone, and glass. For ranges greater than 250 SLM, 416 SS and nickel replace brass.

Power Supply

Units require 12 to 30 Vdc for models up to 20 SLM (typical supply current 0.250 A) and 24 to 30 Vdc for units 50 SLM and larger (typical supply current 0.75 A).

Key Product Differences

The series includes specific model families distinguished by output configuration, valve integration, and measurement mode:

• FMA-26XXA Base Models: Standard mass flow controllers with 0 to 5 Vdc input/output and RS232.
• -I Suffix: Adds optional 4 to 20 mA output (standard remains 0 to 5 V).
• -I2 Suffix: Provides two 4 to 20 mA outputs.
• -V2 Suffix: Provides two 0 to 5 V outputs.
• -IN Suffix: Replaces standard input with optional 4 to 20 mA input.
• -VOL Suffix: Sets volumetric flow rate as the standard output and control loop setpoint.
• -P (Valve) Option: Integrates a positive shut-off valve; available on models up to 20 SLM with 1/4" welded male VCR fittings.
• -T or -P (Output Scale): Alternate secondary output scales for temperature (-T) or pressure (-P).
• -SCFH Option: Units scaled in SCFH; requires specification of desired range.
• -TOT Option: Adds a totalizer with 6-digit counter resolution (e.g., liters at 1/100 liter or 1 liter).

The series supports multi-drop configurations allowing up to 26 units on one serial connection over distances of 46 m (150'). Standard calibrations are performed for air @ 5 psig (0 to 1 LPM), 15 psig (2 to 10 LPM), 30 psig (20 to 100 LPM), and 50 psig (200 LPM and greater) at ambient 25°C (77°F).