Brooks Instrument GF125C Metal-Sealed Mass Flow Controller
About this part
GF125C-103954 is a configured Brooks Instrument GF125C metal-sealed thermal mass flow controller in the GF100/GF120/GF125 family. Official Brooks GF100-series documentation covers GF125 models as high-purity gas MFCs/meters with configurable gas, range, valve, fitting, and communication options. Stored exact-part listing evidence associates this configured code with AMAT 0190-49897 context and 15000 SCCM; one surplus lot also identifies the gas as N2. Treat those as observed configured-unit details, not universal model-wide specifications
Unit-specific configuration
Observed configuration
Historical listing records identify this part as N2 observed in one surplus lot listing; not confirmed by an official Brooks build sheet at 15000 SCCM. Exact gas, range, fittings, valve configuration, and communication interface must be verified from the physical unit label.
Configurations vary. Verify the exact unit before choosing a replacement.
Observed gasN2 observed in one surplus lot listing; not confirmed by an official Brooks build sheet
Observed full-scale range15000 SCCM
Configuration statusVerify from unit label
Application classSemiconductor/high-purity gas delivery
CategoryFlow Control
Specifications
Identification
Device type
Metal-sealed high-purity thermal mass flow controller for gases
Series family
Brooks GF100 / GF120 / GF125 Series
Configured model code
GF125C-103954
Configuration
Configured-unit rule
Gas, full-scale range, communication interface, valve state, fitting package, surface finish, and process options vary by configured model code and should be confirmed from the unit label or Brooks build record
Applications
Application domain
Semiconductor, MOCVD, thin-film, and other high-purity gas flow-control applications
Flow
Official family flow-range context
Brooks GF100-series documentation lists GF100/GF120/GF125 full-scale flow ranges from 3 sccm to 55 slm, depending on model and configuration
Observed configured range
Stored exact-part listing evidence identifies GF125C-103954 as 15000 SCCM; this is observed configured-unit evidence, not an official Brooks build-sheet value
Observed configured gas
One surplus lot listing associates GF125C-103954 / 0190-49897 with N2; confirm gas service on the physical label before reuse
Control range
Official documentation lists 2-100% for normally closed valve configurations and 3-100% for normally open valve configurations
Gas/range programmability
Brooks MultiFlo gas and range configurability is documented for GF1XX-series devices; availability and programmed gas/range depend on the exact unit configuration
Performance
Flow accuracy
Official GF100/GF120/GF125 analog and DeviceNet documentation lists +/-1% of set point above 35-100% and +/-0.35% full scale over 2-35%, based on factory N2 calibration
Repeatability and reproducibility
Official GF100/GF120/GF125 documentation lists 5-100% as +/-0.15% of set point and 2-5% as +/-0.015% of full scale
Settling-time context
For normally closed GF100/GF120/GF125 configurations, official documentation lists 500 ms settling time for the 7201-30000 sccm bin and less than 700 ms for the 30001-55000 sccm bin
Pressure transient insensitivity
Official GF100-series documentation lists GF125 pressure transient insensitivity as less than 5% of set point for up to a 5 psi/sec upstream pressure spike
Materials
Wetted path standard
Official GF100/GF120/GF125 documentation lists SEMI F20 HP compliant wetted materials
Wetted materials context
Documented wetted materials include 316L VIM/VAR, Hastelloy C-22, 316L stainless steel, 304 stainless steel, KM-45, and PCTFE on optional zero-leak-by valve configurations
Controls
Communication interfaces
Brooks documentation lists RS485/analog and DeviceNet options for GF100/GF120/GF125 models, with EtherCAT covered by separate GF100-series EtherCAT documentation; exact interface is configuration dependent
Diagnostic/service port
Official GF100/GF120/GF125 documentation lists an independent RS485 diagnostic/service port via 2.5 mm jack
Electrical
Power context
Official documentation lists DeviceNet consumption up to 545 mA at +11 to 25 Vdc and RS485/analog power at 6 W maximum using +/-15 Vdc or +24 Vdc, depending on configuration
