Brooks Instrument 585 EMH Series User manual

Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017 Brooks®Model 585xEMH
Brooks®Model 585xEMH
High Temperature Mass Flow Controllers
Model 5850EMH High Temperature
Thermal Mass Flow Controller Model 5851EMH High Temperature Thermal Mass Flow Controller

Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
Brooks®Model 585xEMH
ESD (Electrostatic Discharge)
CAUTION: This instrument contains electronic components that are susceptible to damage by static electricity. Proper handling procedures must be observed
during the removal, installation or other handling of internal circuit boards or devices.
Handling Procedure:
1. Power to unit must be removed.
2. Personnel must be grounded, via a wrist strap or other safe, suitable means before any printed circuit card or other internal device is installed,
removed or adjusted.
3. Printed circuit cards must be transported in a conductive container. Boards must not be removed from protective enclosure until immediately before
installation. Removed boards must immediately be placed in protective container for transport, storage or return to factory.
Comments
This instrument is not unique in its content of ESD (electrostatic discharge) sensitive components. Most modern electronic designs contain components
that utilize metal oxide technology (NMOS, SMOS, etc.). Experience has proven that even small amounts of static electricity can damage or destroy these
devices. Damaged components, even though they appear to function properly, exhibit early failure.
Brooks Instrument designs, manufactures and tests its products to meet many national and international standards. These products must be properly
installed, operated and maintained to ensure they continue to operate within their normal specifications. The following instructions must be adhered to
and integrated into your safety program when installing, operating and maintaining Brooks Instrument products.
• To ensure proper performance, use qualified personnel to install, operate, update, program and maintain the product.
• Read all instructions prior to installing, operating and servicing the product. If this instruction manual is not the correct manual, please see back cover
for local sales office contact information. Save this instruction manual for future reference.
WARNING: Do not operate this instrument in excess of the specifications listed in the Instruction and Operation Manual. Failure to heed
this warning can result in serious personal injury and / or damage to the equipment.
• If you do not understand any of the instructions, contact your Brooks Instrument representative for clarification.
• Follow all warnings, cautions and instructions marked on and supplied with the product.
WARNING: Prior to installation ensure this instrument has the required approval ratings to meet local and national codes. Failure to heed this warning can
result in serious personal injury and / or damage to the equipment.
• Install your equipment as specified in the installation instructions of the appropriate instruction manual and per applicable local and national codes.
Connect all products to the proper electrical and pressure sources.
• Operation: (1) Slowly initiate flow into the system. Open process valves slowly to avoid flow surges. (2) Check for leaks around the flow meter inlet
and outlet connections. If no leaks are present, bring the system up to the operating pressure.
• Please make sure that the process line pressure is removed prior to service. When replacement parts are required, ensure that qualified people use
replacement parts specified by Brooks Instrument. Unauthorized parts and procedures can affect the product's performance and place the safe
operation of your process at risk. Look-alike substitutions may result in fire, electrical hazards or improper operation.
• Ensure that all equipment doors are closed and protective covers are in place to prevent electrical shock and personal injury, except when
maintenance is being performed by qualified persons.
WARNING: For liquid flow devices, if the inlet and outlet valves adjacent to the devices are to be closed for any reason, the devices must be completely
drained. Failure to do so may result in thermal expansion of the liquid that can rupture the device and may cause personal injury.
All pressure equipment with an internal pressure greater than 0.5 bar (g) and a size larger than 25mm or 1" (inch) falls under the Pressure Equipment Directive (PED).
• The Specifications Section of this manual contains instructions related to the PED directive.
• Products described in this manual are in compliance with EN directive 2014/34/EU.
• All Brooks Instrument Flowmeters fall under fluid group 1.
• Products larger than 25mm or 1" (inch) are in compliance with PED category I, II or III.
• Products of 25mm or 1" (inch) or smaller are Sound Engineering Practice (SEP).
The Brooks Instrument (electric/electronic) equipment bearing the CE mark has been successfully tested to the regulations of the Electro Magnetic
Compatibility (EMC directive 2014/30/EU).
Special attention however is required when selecting the signal cable to be used with CE marked equipment.
Quality of the signal cable, cable glands and connectors:
Brooks Instrument supplies high quality cable(s) which meets the specifications for CE certification.
If you provide your own signal cable you should use a cable which is overall completely screened with a 100% shield.
“D” or “Circular” type connectors used should be shielded with a metal shield. If applicable, metal cable glands must be used providing cable screen clamping.
The cable screen should be connected to the metal shell or gland and shielded at both ends over 360 Degrees.
The shield should be terminated to an earth ground.
Card Edge Connectors are standard non-metallic. The cables used must be screened with 100% shield to comply with CE certification.
The shield should be terminated to an earth ground.
For pin configuration : Please refer to the enclosed Instruction Manual.
European Pressure Equipment Directive (PED)
European Electromagnetic Compatibility (EMC)
Essential Instructions
Read before proceeding!

Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017 Brooks®Model 585xEMH
Dear Customer,
We appreciate this opportunity to service your flow measurement and control requirements with a Brooks
Instrument device. Every day, flow customers all over the world turn to Brooks Instrument for solutions to their
gas and liquid low-flow applications. Brooks provides an array of flow measurement and control products for
various industries from biopharmaceuticals, oil and gas, fuel cell research and chemicals, to medical devices,
analytical instrumentation, semiconductor manufacturing, and more.
The Brooks product you have just received is of the highest quality available, offering superior performance,
reliability and value to the user. It is designed with the ever changing process conditions, accuracy requirements
and hostile process environments in mind to provide you with a lifetime of dependable service.
We recommend that you read this manual in its entirety. Should you require any additional information concerning
Brooks products and services, please contact your local Brooks Sales and Service Office listed on the back cover
of this manual or visit www.BrooksInstrument.com
Yourssincerely,
Brooks Instrument

Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
Brooks®Model 585xEMH
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Brooks®Model 585xEMH
Contents
Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May, 2017
Paragraph Page
Number Number
Section 1 Introduction
1-1 How to Use This Manual ............................................................................................................1-1
1-2 Description .................................................................................................................................1-1
1-3 Specifications .............................................................................................................................1-1
Section 2 Installation
2-1 General ......................................................................................................................................2-1
2-2 Receipt of Equipment.................................................................................................................2-1
2-3 Recommended Storage Practice ...............................................................................................2-1
2-4 Return Shipment ........................................................................................................................2-2
2-5 Transit Precautions ....................................................................................................................2-2
2-6 Removal from Storage ...............................................................................................................2-2
2-7 Installation ..................................................................................................................................2-2
2-8 Electrical Interface......................................................................................................................2-5
2-9 Operation Procedure..................................................................................................................2-6
Section 3 Operation
3-1 Overview ....................................................................................................................................3-1
3-2 Connection and Controls............................................................................................................3-1
3-3 Theory of Operation ...................................................................................................................3-3
3-4 Features .....................................................................................................................................3-5
3-5 Adjustment Potentiometers ........................................................................................................3-6
3-6 ZeroAdjustment .........................................................................................................................3-7
3-7 Calibration Procedure ................................................................................................................3-7
3-8 Response Adjustment ...............................................................................................................3-10
Section 4 Maintenance & Troubleshooting
4-1 Overview ....................................................................................................................................4-1
4-2 Troubleshooting..........................................................................................................................4-2
4-3 Gas Conversion Factors ............................................................................................................4-5
4-4 Orifice Sizing .............................................................................................................................4-13
4-5 Restrictor Sizing ........................................................................................................................4-17
Section A Essential Instructions............................................................................................................ A-1
Warranty, Local Sales/Service Contact Information....................................................................... Back Cover

ii
Brooks®Model 585xEMH
Contents Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May, 2017
Figures
Figure Page
Number Number
1-1 Dimensions - Model 585xEMH with D-Connector and VCR Fittings ..........................................1-3
2-1 MFC Mounting Hole Positions for Models 5850EMH & 5851EMH.............................................2-3
2-2 Connecting and Tightening Process Connections......................................................................2-4
2-3 Remote Electronics Box Mounting Diagram ..............................................................................2-5
2-4 Common Electrical Hookups......................................................................................................2-6
3-1 Model 585xEMH Controller Components...................................................................................3-1
3-2 ExternallyAccessibleAdjustments at Remote Electronics Box..................................................3-2
3-3 15-Pin D-Sub Connector at Remote Electronics ........................................................................3-2
3-4 15-Pin D-Connector Shielded Cable Hookup Diagram ..............................................................3-2
3-5 Flow Sensor Operational Diagram .............................................................................................3-3
3-6 Flow Control System Block Diagram..........................................................................................3-4
3-7 Customer Connections and Settings..........................................................................................3-4
3-8 Bench Troubleshooting Circuit ...................................................................................................3-8
3-9 ResponseAdjustment ...............................................................................................................3-11
4-1 Model 585xH Orifice Sizing Nomograph ...................................................................................4-14
4-2 Example Nomograph ................................................................................................................4-17
Tables
Table Page
Number Number
1-1 585xEMH Specifications ............................................................................................................1-2
4-1 BenchTroubleshooting ..............................................................................................................4-4
4-2 SensorTroubleshooting .............................................................................................................4-5
4-3 Conversion Factors ....................................................................................................................4-7

1-1
Section 1 Introduction
Brooks®Model 585xEMH
Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
1-1 How to Use This Manual
This instruction manual is intended to provide the user with all the
information necessary to install, operate and maintain the Brooks®Models
5850EMH and 5851EMH.
This manual is organized into the following sections:
Section 1. Introduction
Section 2. Installation
Section 3. Operation
Section 4. Maintenance
AppendixA Essential Instructions
Back Cover Warranty, Local Sales/Service Contact Information
1-2 Description
The Brooks Models 5850EMH and 5851EMH Mass Flow Controllers are
used in gas flow handling systems that require high ambient/operating
temperatures such as vapor flow control. Unlike standard mass flow
controllers, the 585xEMH has two distinct modules connected by a signal
cable. The controller module is mounted in the process line and the remote
electronics module is mounted away from the high temperature
environment. The Models 5850EMH and 5851EMH incorporate metal
seals or welded joints, insuring leak integrity for high purity and high
vacuum applications. Reducing the amount of internal threads makes the
design less prone to system contamination. The control electronics and
flow sensor designs have been well- proven in precision gas delivery
systems. Standard features include:
• High leak integrity (less than 10-11 PA.m3/s (10-10 atm-cc/sec) He)
• High purity 316LStainless Steel
• All metal seals
• Particulate free
• Wide flow range (0.003 through 100 slpm)
• Helium leak check ports
• Class 100 Clean Room assembly and calibration
• Low command flow cutoff
• TTLcompatible “valve off” function
1-3 Specifications

1-2
Brooks®Model 585xEMH
Section 1 Introduction Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
Table 1-1 585xEMH Specifications
PP
PP
Performanceerformance
erformanceerformance
erformance 5850EMH5850EMH
5850EMH5850EMH
5850EMH 5851EMH5851EMH
5851EMH5851EMH
5851EMH
Flow RangeFlow Range
Flow RangeFlow Range
Flow Range 0.003 - 30 lpm (N2 equivalent) 10 - 100 lpm (N2 equivalent)
FlowFlow
FlowFlow
Flow AccurAccur
AccurAccur
Accuracyacy
acyacy
acy ±1% full scale
ConCon
ConCon
Contrtr
trtr
trol Rangeol Range
ol Rangeol Range
ol Range 5-100%
RepeatabilityRepeatability
RepeatabilityRepeatability
Repeatability ±0.25% of rate
LinearityLinearity
LinearityLinearity
Linearity Included in accuracy
ResponseResponse
ResponseResponse
Response TimeTime
TimeTime
Time (Settling time within ± 2% < 3 sec
for 0 - 100% command step)
RatingsRatings
RatingsRatings
Ratings
OperOper
OperOper
Operatingating
atingating
ating TT
TT
Temperemper
emperemper
emperaturatur
aturatur
ature Rangee Range
e Rangee Range
e Range 85 - 105°C (41 - 221°F)
Maximum PrMaximum Pr
Maximum PrMaximum Pr
Maximum Pressuressur
essuressur
essure Ratinge Rating
e Ratinge Rating
e Rating 1 MPaG (145 psig)
PrPr
PrPr
Pressuressur
essuressur
essure Differe Differ
e Differe Differ
e Differenen
enen
ential (Contial (Con
tial (Contial (Con
tial (Contrtr
trtr
troller)*oller)*
oller)*oller)*
oller)* 50 -350 kPa (7 - 50 psid) 50 - 350 kPa (7 - 50 psid)
* Specify the operating differential pressure at time of request.
Leak InLeak In
Leak InLeak In
Leak Integritytegrity
tegritytegrity
tegrity 1x10-11 Pa.m3/s (1 x 10-10 atm.cc/s) Helium
MecMec
MecMec
Mechanicalhanical
hanicalhanical
hanical
VV
VV
Valvealve
alvealve
alve TT
TT
Typeype
ypeype
ype Normally Closed, Normally Open
PrimaryPrimary
PrimaryPrimary
Primary WW
WW
Wetted Materialsetted Materials
etted Materialsetted Materials
etted Materials 316L and high alloy ferritic stainless steel
VV
VV
Valve Seat Materialalve Seat Material
alve Seat Materialalve Seat Material
alve Seat Material 316L stainless steel
PrPr
PrPr
Process Connectionocess Connection
ocess Connectionocess Connection
ocess Connection 1/4” MVCR 1/2” MVCR or 1/4” MVCR
Communication PrCommunication Pr
Communication PrCommunication Pr
Communication Protocolotocol
otocolotocol
otocol
Electrical ConnectionElectrical Connection
Electrical ConnectionElectrical Connection
Electrical Connection 1 x 15-pin Male D-sub
Input SignalInput Signal
Input SignalInput Signal
Input Signal 0 - 5 Vdc linearly proportional to required flow
Output SignalOutput Signal
Output SignalOutput Signal
Output Signal 0 - 5 Vdc linearly proportional to flow rate
PP
PP
Power Requirower Requir
ower Requirower Requir
ower Requiremenemen
emenemen
ementt
tt
t ±15 Vdc @ 350 mA (max)

1-3
Section 1 Introduction
Brooks®Model 585xEMH
Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
5851EMH
5850EMH
Figure 1-1 Dimensions - Model 585xEMH with D-Connector and VCR Fittings

1-4
Brooks®Model 585xEMH
Section 1 Introduction Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
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2-1
Brooks®Model 585xEMH
Section 2 Installation
Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
2-1 General
This section contains the procedures for the receipt and installation of the
instrument. See Section 1 for dimensional and connection requirements.
Do not attempt to start the system until the instrument has been
permanently installed. It is important that the start-up procedures be
followed in the exact sequence presented.
2-2 Receipt of Equipment
When the equipment is received, the outside packing case should be
checked for damage incurred during shipment. If the packing case is
damaged, the local carrier should be notified at once regarding his liability.
A report should be submitted to the nearest Brooks Instrument location
listed on the Global Service Network page on our website:
BrooksInstrument.com/GlobalSupportCenters
Remove the envelope containing the packing list. Carefully remove the
instrument from the packing case. Make sure spare parts, accessories and
documentation are not discarded with the packing materials. Inspect for
damaged or missing parts.
2-3 Recommended Storage Practice
If intermediate or long-term storage of equipment is required, it is
recommended that the equipment be stored in accordance with the
followingconditions:
a. Within the original shipping container.
b. Stored in a sheltered area, preferably a warm, dry, heated warehouse.
c.Ambient temperature 21°C (70°F) nominal, 32°C (90°F) maximum, 45°F
(7°C) minimum.
d. Relative humidity 45% nominal, 60% maximum, 25% minimum
2-4 Return Shipment
Prior to returning any instrument to the factory for any reason, visit our
website for instructions on how to obtain a Return MaterialsAuthorization
Number (RMA#) and complete a Decontamination Statement to
accompany it: BrooksInstrument.com/Service.All instruments returned to
Brooks also require a Material Safety Data Sheet (MSDS) for the fluid(s)
used in the instrument. Failure to provide this information will delay
processing of the instrument.
Instrument must have been purged in accordance with the following:

2-2
Brooks®Model 585xEMH
Section 2 Installation Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
2-5 Transit Precautions
To safeguard the instrument against transportation damage, it is
recommended to keep the instrument in its factory container until ready for
installation.
2-6 Removal from Storage
Upon removal of the instrument from storage, a visual inspection should be
conducted to verify its “as-received” condition. If the instrument has been
subject to storage conditions in excess of those recommended (See
Section 2-3), it should be subjected to a pneumatic pressure test in
accordance with applicable vessel codes
2-7 Installation
Unlike most flow controllers, the Model 585xEMH requires that two
separate components be mounted close enough together that the supplied
cable is sufficient.The two modules and the signal cable are calibrated
together at the factory as a matched set. Ensure that the two components
are mounted close enough together that the supplied cable length is
sufficient.
Controller
Prior to installation make certain all piping is clean and free of obstructions,
for tubing installations. Install the piping in such a manner that permits easy
access to the instrument if it needs to be removed for cleaning or test
benchtroubleshooting.
Recommended installation procedures:
a. The Model 585xEMH should be located in a clean, dry atmosphere
relatively free from shock and vibration.
b. Leave sufficient room for access to the 15-pin Dsub connector located at
the top portion of the cover pointing towards the control valve.
c. Install in such a manner that permits easy removal if the instrument
requires servicing.

2-3
Brooks®Model 585xEMH
Section 2 Installation
Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
d. The Model 585xEM Mass Flow Controller can be installed in any
position. However, mounting in orientations other than the original factory
calibration (see calibration data sheet) can result in a full scale shift after
re-zeroing.
e. The controller must be positioned so that the gas flow is in the direction
of the arrow stamped on the controller base.The controller is designed and
calibrated to be mounted in the position indicated on the calibration sheet.
f. Match the mounting holes on the bottom of the flow controller with those
on the mounting surface. Using one #8-32 screw or two M4 screws, mount
the flow controller. See Figure 2-1 for mounting hole positions.
Figure 2-1 MFC Mounting Hole Positions for Models 5850EMH & 5851EMH
5850EMH
5851EMH
Inch
[mm]

2-4
Brooks®Model 585xEMH
Section 2 Installation Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
g. Once the controller is correctly mounted, connect the inlet and outlet
VCR®fittings to the gas supply line.
1. Install new gaskets compatible with the gas to be used.
2. Tighten nut finger tight.
3. Tighten in accordance with the Swagelok®VCR®fitting installation
specifications
Figure 2-2 Connecting and Tightening Process Connections
N.B. The control valve in the Model 585xEMH provides precision control
and is not designed for positive shut-off. If positive shut-off is required, it is
recommended that a separate shut-off valve be installed in-line.
Remote Electronics Box
The remote electronics box must be mounted outside of the high
temperature area (ambient temperature <50° C) using the two mounting
holes located in the base of the remote electronics box. To gain access to
the mounting holes, remove the four screws on the cover of the remote
electronics box. See Figure 2-3.

2-5
Brooks®Model 585xEMH
Section 2 Installation
Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
Figure 2-3 Remote Electronics Box Mounting Diagram
The remote electronics box can be mounted in any position that is
convenient, within reach of the high temperature cable. The temperature
limit of the electronics is 0-50°C (32°F-122°F).
Connect the Remote Electronics Box with the Controller utilizing the 15-pin
D sub connector on the end of the cable which is wired to the Remote
Electronics Box.
2-8 Electrical Interface
To insure proper operation, the Model 585xEMH must be connected per
Figure 3-4. As a minimum, the following connections must be made:
Voltage I/O Version
• Chassis Ground
• Signal Common
• Signal Output
• +15 Vdc Supply
• -15 Vdc Supply
• Command Input
• Command Common
Supply Common

2-6
Brooks®Model 585xEMH
Section 2 Installation Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
Figure 2-4 Common Electrical Hookups
2-9 Operation Procedure
a. Mount the controller & remote electronics box in their final location and
orientation.
b.Apply any and all heater devices and thermal insulation around the
controller and the process lines.
c.Apply power to the device and to any external heaters for approximately
60 minutes to allow the instrument to warm up and stabilize its
temperature.
d. Prior to introducing process gas, insure that the MFC and gas lines have
been thoroughly purged with clean, dry N2.

3-1
Brooks®Model 585xEMH
Section 3 Operation
Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May, 2017
3-1 Overview
After the flowmeter has been properly installed in the process line, it is
ready for operation. When initiating flow, slowly open the valve to avoid a
flow surge. Using a bypass can help in bringing the flow on smoothly. Avoid
starting a pump to supply the flowmeter without the use of a valve
upstream of the flowmeter.
This section contains the following information:
• Features and Jumper Configurations
• Theory of Operation
• Adjustment Potentiometers
• Calibration and ResponseAdjustments
3-2 Connections and Controls
Figure 3-1 shows the locations of the Model 585xEMH controller
connections. Figure 3-2 identifies the externally accessible adjustment
potentiometers located on the remote electronics box on the side opposite
the 15-pin D sub connector. Figure 3-3 shows the 15 pin D-sub connector.
Figure 3-4 identifies the pin out diagram for the 15 pin D-sub connector.
Figure 3-1 Model 585xEMH Controller Components
Electronics Cover
Inlet
Connector
Outlet
Connector
Control Vlave
Remote Electronics
Connection

3-2
Brooks®Model 585xEMH
Section 3 Operation Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
Figure 3-2 Externally Accessible Adjustments at Remote Electronics Box
Figure 3-3 External 15-Pin D-Sub Connector at Remote Electronics
15 Pin D-Connector15 Pin D-Connector
15 Pin D-Connector15 Pin D-Connector
15 Pin D-Connector
Pin Function
1 Command Common
2 0-5 Volt, Signal Output
3 Not Used
4 Not Used
5 +15 Vdc Supply
6 -15 Vdc Supply
7 Valve Voltage Out
8 Command Input
9 Supply Voltage Common
10 0-5 Volt Signal Common
11 +5 Vdc Reference Output
12 Valve Override
13 Not Used
14 Chassis Ground
15 Not Used
Figure 3-4 15-Pin D-Connector Shielded Cable Hookup Diagram

3-3
Brooks®Model 585xEMH
Section 3 Operation
Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May, 2017
3-3 Theory of Operation
The thermal mass flow sensing technique used in the Model 585xEMH
operates as follows:
Aprecision power supply provides a constant power heat input (P) at the
heater which is located at the midpoint of the sensor tube. Refer to Figure
3-3.At zero, or no flow conditions, the heat reaching each temperature
sensor is equal. The temperatures T1 and T2, therefore, are equal. When
gas flows through the sensor tube, the upstream sensor is cooled and the
downstream sensor is heated which produces a temperature difference.
The temperature difference T2-T1 is directly proportional to the gas mass
flow. The equation is:
Where: DT =A* P * Cp* m
DT = Temperature difference T2 - T1 (K)
Cp= Specific heat of the gas at constant pressure (kJ/kg-K)
P = Heater power (kJ/s)
m = Mass flow (kg/s)
A = Constant of proportionality (s2-K2/kJ2)
Abridge circuit interprets the temperature difference and a differential
amplifier generates a linear 0-5 Vdc signal directly proportional to the gas
mass flow rate.
Figure 3-5 Flow Sensor Operational Diagram

3-4
Brooks®Model 585xEMH
Section 3 Operation Installation and Operation Manual
X-TMF-585xEMH-MFC-eng
Part Number: 541B212AAG
May,2017
Figure 3-6 Flow Control System Block Diagram
Figure 3-7 Customer Connections and Settings