Dwyer GFC User Manual

Technical Data Sheet No. TD9709M Rev. F
Date of issue: May 2006

OPERATING MANUAL

FOR GFC MASS FLOW CONTROLLERS

P.O. Box 373
Michigan City, IN 46361 USA
Phone: [phone]
FAX: [phone]

E mail: [e-mail]

Internet: http://www.dwyer-inst.com

Dwyer reserves the right to make changes to information and specifications in this
manual without notice.

TABLE OF CONTENTS

1. UNPACKING THE GFC MASS FLOW CONTROLLER........................

1.1 Inspect Package for External Damage..............................................

1.2 Unpack the Mass Flow Controller.......................................................

1.3 Returning Merchandise for Repair.....................................................

2. INSTALLATION....................................................................

2.1 Primary Gas Connections.................................................................

2.2 Electrical Connections......................................................................

2.2.1 Valve Control Configuration.......................................................

2.2.2 Remote LCD Readouts.................................................................

2.2.3 Panel Mounting Readouts............................................................

3. PRINCIPLE OF OPERATION....................................................

4. SPECIFICATIONS..................................................................

4.1 CE Compliance................................................................................

5. OPERATING INSTRUCTIONS.....................................................

5.1 Preparation and Warm Up................................................................

5.2 Flow Signal Output Readings..............................................................

5.3 Swamping Condition...........................................................................

5.4 Setpoint Reference Signal..................................................................

5.5 Valve OFF Control (Open Collector NPN Compatible)..........................

5.6 Valve Test/Purge.................................................................................

10
10
11
12
13

1
1
1
1

2
2
2
4
4
5

5

6
7

9
9

6. MAINTENANCE....................................................................

6.1 Introduction........................................................................................

6.2 Flow Path Cleaning..............................................................................

6.2.1 Cleaning the Inlet Filter Screen in GFC-110/111 Models...............

6.2.2 Cleaning the Inlet Filter Screen in GFC-113/114 Models..........

6.2.3 Valve Maintenance for GFC-110/111/113/114 Models.................

7. CALIBRATION PROCEDURES....................................................

7.1 Flow Calibration...................................................................................

7.2 Calibration of GFC Mass Flow Controllers.......................................

7.2.1 Connections and Initial Warm Up...............................................

7.2.2 Zero Adjustment............................................................................

7.2.3 SPAN Adjustment.........................................................................

7.3 Linearity Adjustment..........................................................................

7.3.1.1 Disable Solenoid Valve in GFC-110/111/113/114 Models.........

7.3.1.2 Open Motorized Valve in GFC-1143/1144/1145 Models............

13
13
13
14
14
15

16
16
17
17
18
18
18
18
18

7.3.2 Connections and Initial Warm Up............................................

7.3.3 ZERO Adjustment...................................................................

7.3.4 25% Flow Adjustment...............................................................

7.3.5 50% Flow Adjustment..............................................................

7.3.6 75% Flow Adjustment..............................................................

7.3.7 100% Flow Adjustment............................................................

7.3.8.1 Valve Adjustment for GFC-110/111/113/114.............................

7.3.8.2 Valve Adjustment for GFC-1143/1144/1145..............................

7.3.9 Full Scale Flow Adjustment...................................................

7.3.10 25% Flow Adjustment...........................................................

7.3.11 50% Flow Adjustment...........................................................

7.3.12 75% Flow Adjustment..........................................................

7.3.13 100% Flow Adjustment.........................................................

7.4 LCD Display Scaling..................................................................

7.4.1 Access LCD Display Circuit......................................................

7.4.2 Adjust Scaling.......................................................................

7.4.3 Change Decimal Point...........................................................

19
19
19
19
20
20
20
20
20
20
20
21
21
21
21
21
22

8. TROUBLESHOOTING.............................................................

8.1 Common Conditions...........................................................................

8.2 Troubleshooting Guide.......................................................................

8.3 Technical Assistance............................................................................

9. CALIBRATION CONVERSIONS FROM REFERENCE GASES................

APPENDIX 1 COMPONENT DIAGRAM....................................................

APPENDIX 2 GAS FACTOR TABLE ("K" FACTORS)..................................

APPENDIX 3 DIMENSIONAL DRAWINGS.................................................

APPENDIX 4 WARRANTY..........................................................................

22
22
23
25

25

26

28

32

36

1. UNPACKING THE GFC MASS FLOW CONTROLLER

1.1 Inspect Package for External Damage

Your GFC Mass Flow Controller was carefully packed in a sturdy cardboard car­ton, with anti-static cushioning materials to withstand shipping shock. Upon
receipt, inspect the package for possible external damage. In case of external
damage to the package contact the shipping company immediately.

1.2 Unpack the Mass Flow Controller

Open the carton carefully from the top and inspect for any sign of concealed ship­ping damage. In addition to contacting the shipping carrier please forward a copy
of any damage report to your distributor or Dwyer directly.

When unpacking the instrument please make sure that you have all the items indi­cated on the Packing List. Please report any shortages promptly.

1.3 Returning Merchandise for Repair

Please contact the customer service representative of your distributor or Dwyer if
you purchased your Mass Flow Controller directly, and request a Return

Authorization Number (RAN). Equipment returned without an RAN will not
be accepted. Dwyer reserves the right to charge a fee to the customer for equip-

ment returned under warranty claims if the instruments are tested to be free from
warrantied defects.

Shipping charges are borne by the customer. Items returned "collect" will
not be accepted!

It is mandatory that any equipment returned for servicing be purged and neutral­ized of any dangerous contents including but not limited to toxic, bacterially infec­tious, corrosive or radioactive substances. No work shall be performed on a
returned product unless the customer submits a fully executed, signed SAFETY
CERTIFICATE. Please request form from the Service Manager.

1

2. INSTALLATION

2.1 Primary Gas Connections

Please note that the GFC Mass Flow Controller will not operate with liquids. Only
clean gases are allowed to be introduced into the instrument. If gases are con­taminated they must be filtered to prevent the introduction of impediments into the
sensor.

Caution: GFC transducers should not be used for monitoring OXYGEN
gas unless specifically cleaned and prepared for such application.



For more information, contact your distributor or Dwyer.

0

Attitude sensitivity of the Mass Flow Controller is ±15
flow path of the flow meter must be horizontal within those stated limits. Should
there be need for a different orientation of the meter, re-calibration may be nec­essary. It is also preferable to install the GFC transducer in a stable environment,
free of frequent and sudden temperature changes, high moisture, and drafts.

Prior to connecting gas lines inspect all parts of the piping system including fer­rules and fittings for dust or other contaminants. Be sure to observe the direction
of gas flow as indicated by the arrow on the front of the meter when connecting
the gas system to be monitored.

Insert tubing into the compression fittings until the ends of the properly sized tub­ings home flush against the shoulders of the fittings. Compression fittings are to
be tightened according to the manufacturer's instructions to one and one quarter
turns. Avoid over tightening which will seriously damage the Restrictor Flow
Elements (RFE's)!

. This means that the gas

Compression fittings should not be removed unless the meter is being cleaned or
calibrated for a new flow range.

Using a Helium Leak Detector or other equivalent method perform a thorough
leak test of the entire system. (All GFC's are checked prior to shipment for leak­age within stated limits. See specifications in this manual.)

2.2 Electrical Connection

GFC transducers require a +12VDC (+24VDC optional) power supply with a min­imum current rating of 1100 mA to operate. The operating power input is supplied
via the 15-pin "D" connector located at the side of the flow transducer enclosure.
On GFC's purchased without an LCD readout, a readout panel meter, digital mul­timeter, or other equivalent device is required to observe the flow signal.

A built in SETPOINT potentiometer is supplied with all GFC transducers for local
control of the flow. A variable analog 0 to 5 VDC (or 4 to 20 mA) reference input
is required for remote control.

2

PIN FUNCTION

1 Flow Signal Common
2 0 to 5 VDC Flow Signal Output
3 Common
4 Open Purge
5 Common, Power Supply
6 (unassigned)
7 +12 VDC (+24 VDC*) Power Supply
8 Remote Setpoint
9 4 to 20 mA Return (Common)
10 Common, Setpoint Signal
11 +5VDC Reference for Remote Setpoint
12 Valve Off Control

(Open Collector Compatible)
13 +12 VDC (+24 VDC *) Power Supply
14 4 to 20 mA Flow Signal Output
15 Chassis Ground

FIGURE 2-a GFC 15-PIN "D" CONNECTOR CONFIGURATION

*+24 VDC power supply configuration is optional for only GFC-110/111/113/114
models.

WARNING: DO NOT CONNECT 24Vdc POWER SUPPLY UNLESS
YOUR GFC CONTROLLER WAS ORDERED AND CONFIGURED



FOR 24Vdc

Important notes:

In general, "D" Connector numbering patterns are standardized. There are, how­ever, some connectors with nonconforming patterns and the numbering sequence
on your mating connector may or may not coincide with the numbering sequence
shown in our pin configuration table above. It is imperative that you match the
appropriate wires in accordance with the correct sequence regardless of the par­ticular numbers displayed on your mating connector.

Make sure power is OFF when connecting or disconnecting any cables in the sys­tem.

The power input is protected by a 1600mA M (medium time-lag) resettable fuse.
If a shorting condition or polarity reversal occurs, the fuse will cut power to the flow
transducer circuit. Disconnect the power to the unit, remove the faulty condition,
and reconnect the power. The fuse will reset once the faculty condition has been
removed.

Use of the GFC flow transducer in a manner other than that specified in this manu­al or in writing from Dwyer, may impair the protection provided by the equipment.

3

FIGURE 2-b, POTENTIOMETER AND JUMPER LOCATIONS

2.2.1 Valve Control Configuration

There are three basic valve control options. (a) LOCAL or REMOTE control; (b) 0
to 5 VDC or 4 to 20 mA setpoint signal - *note: this only applies for the REMOTE
control configuration; (c) 2% cutoff active or not active. NOTE: 2% cutoff not avail­able for GFC 57 /67 /77. When active, the 2% cutoff will shut off the power to the
valve when a setpoint of less than 2% of the full scale flow range is set. Figure 2­2 shows the jumper configurations for the three basic valve control options.

The factory default jumper settings are: LOCAL control, 2% cutoff, and 0 to 5
VDC.

Function

0 to 5 VDC

4 to 20 mA

local

remote
2% cutoff on
2% cutoff off

2.2.2 Remote LCD Readouts

GFC Mass Flow Controllers are available with optional remote reading LCD dis­plays supplied with a three foot long wire to accommodate most applications. This
configuration includes the upper block element which serves as the LCD readout
mounting. Special lengths of remote extension wiring (up to 9.5 feet [3 meters])
are available on request.

NJ1A

2 - 3
1 - 2

FIGURE 2-c, VALVE CONTROL CONFIGURATION JUMPERS

NJ1B

5 - 6
4 - 5

NJ1C

8 - 9
7 - 8

NJ1D

11 - 12
10 - 11

NJ1E

13 - 14
14 - 15

4

2.2.3 Panel Mounting Readouts

Another option for the GFC Mass Flow Controller is the Panel Mounting Remote
Readout.

In this configuration the LCD readout is supplied with a three foot long extension
wire, and no aluminum housing around the LCD. The LCD readout for panel
mounting includes a bezel with two plastic screws which conveniently fit into a rec­tangular cut-out for panel mounting (see Figure 2d).

FIGURE 2-d CUTOUT DIMENSIONS FOR LCD PANEL MOUNTING.

3. PRINCIPLE OF OPERATION

The stream of gas entering the Mass Flow transducer is split by shunting a small
portion of the flow through a capillary stainless steel sensor tube. The remainder
of the gas flows through the primary flow conduit. The geometry of the primary
conduit and the sensor tube are designed to ensure laminar flow in each branch.
According to principles of fluid dynamics the flow rates of a gas in the two lami­nar flow conduits are proportional to one another. Therefore, the flow rates meas­ured in the sensor tube are directly proportional to the total flow through the trans­ducer.

In order to sense the flow in the sensor tube, heat flux is introduced at two sec­tions of the sensor tube by means of precision wound heater-sensor coils. Heat is
transferred through the thin wall of the sensor tube to the gas flowing inside. As
gas flow takes place heat is carried by the gas stream from the upstream coil to
the downstream coil windings. The resultant temperature dependent resistance
differential is detected by the electronic control circuit. The measured gradient at
the sensor windings is linearly proportional to the instantaneous rate of flow tak­ing place.

An output signal is generated that is a function of the amount of heat carried by
the gases to indicate mass-molecular based flow rates.

GFC Mass Flow Controller models GFC-110/111/113/114 also incorporate a pro­portionating solenoid valve and models GFC-1143/1144/1145 a motorized valve.
The closed loop control circuit of the GFC continuously compares the mass flow
output with the selected flow rate. Deviations from the setpoint are corrected by
compensating valve adjustments, thus maintaining the desired flow parameters.

5

4. SPECIFICATIONS

FLOW MEDIUM: Please note that GFC Mass Flow Controllers are designed to work with
clean gases only. Never try to meter or control flow rates of liquids with any GFC's.

CALIBRATIONS: Performed at standard conditions [14.7 psia (1.01 bars) and 70

0

(21.1

C)] unless otherwise requested or stated.

0

F

ENVIRONMENTAL (per IEC 664): Installation Level II; Pollution Degree II.

ACCURACY: ±1.5% of full scale, including linearity for gas temperatures ranging from

0

59

F to 770F (150C to 250C) and pressures of 5 to 60 psia (0.35 to 4.1 bars).

REPEATABILITY: ±0.5% of full scale.

TEMPERATURE COEFFICIENT: 0.15% of full scale/

0

C.

PRESSURE COEFFICIENT: 0.01% of full scale/psi (0.07 bar).

RESPONSE TIME: GFC-110/111: 300ms time constant; approximately 1 second to

within ±2% of set flow rate for 25% to 100% of full scale flow.

GFC-113/114: 600ms time constant; approximately 2 seconds to
within ±2% of set flow rate for 25% to 100% of full scale flow.

GFC-1143/1144/1145:1800ms time constant; approximately 5
seconds to within ± 2% of set flow rate for 25% to 100% of full
scale flow.

GAS PRESSURE: 500 psig (34.5 bars) max; optimum pressure is 20 psig (1.4 bars).

MAX DIFFERENTIAL PRESSURE: 50 psid for GFC17/37/57/67/77, 40psid for GFC47.

GAS AND AMBIENT TEMPERATURE: 32

0

F to 1220F (00C to 500C).

RELATIVE GAS HUMIDITY: Up to 70%.

LEAK INTEGRITY: 1 x 10

-7

sccs He max to the outside environment.

ATTITUDE SENSITIVITY: No greater than ±15 degree rotation from horizontal to vertical;
standard calibration is in horizontal position.

OUTPUT SIGNALS: Linear 0 to 5 VDC (1000 Ω minimum load impedance) and 4 to 20
mA (50 to 500 Ω loop resistance); 20 mV peak to peak max noise for
GFC-110/111/113/114 and 100 mV peak to peak max noise for GFC-1143/1144/1145.

COMMAND SIGNAL: Analog 0 to 5 VDC (100 Ω input impedance) or 4 to 20 mA (0 to
250 Ω loop resistance).

Contact your distributor or Dwyer for optional RS232 or IEEE488 interfaces.

TRANSDUCER INPUT POWER: +12 VDC, 1100 mA maximum;
GFC-110/111/113/114 have an OPTION of +24 VDC, 650 mA maximum -

IF SPECIFIED AT TIME OF ORDERING AND CONFIGURED ACCORDINGLY.

6

WETTED MATERIALS:

GFC-110/111/113/114/ GFC-1143/1144/1145: 416 Stainless steel and 316 stainless steel

with VITON®O-rings seals; BUNA-N®, NEOPRENE®or KALREZ®O-rings are optional.

GFC-217/237/247/257/267/277: 416 Stainless steel and 316 stainless steel with VITON

®

O-rings seals; BUNA-N®, NEOPRENE®or KALREZ®O-rings are optional.

Dwyer makes no expressed or implied guarantees of corrosion resistance of mass flow
meters as pertains to different flow media reacting with components of meters. It is the
customers sole responsibility to select the model suitable for a particular gas based on
the fluid contacting (wetted) materials offered in the different models.

INLET AND OUTLET CONNECTIONS: GFC-110/111/GFC-113 -¹/₄" compression fittings.

GFC-114/GFC-1143 - ³/₈" compression fittings.
GFC-1144 - ½ " compression fittings.
GFC-45 - ³/₄" FNPT ports.

Optional fittings are: 1/8" or 3/8" compression fittings and 1/4" VCR

®.

LCD DISPLAY: 3½ digit LCD (maximum viewable digits "1999"), 0.5 inch high characters.
On aluminum or stainless steel models the LCD display is built into the upper block element
and may be tilted over 90 degrees for optimal viewing comfort. Remote or panel mounting
remote reading is optional.

Standard readings are in direct engineering units for the given gas and flow rate (i.e. stan­dard liters/minute [slpm], standard cubic centimeters/minute [sccm], standard cubic
feet/hour [scfh], etc.). 0 to 100% LCD calibration scaling is available upon request at time
of order. Contact your distributor or Dwyer when non-standard display settings are desired.

TRANSDUCER INTERFACE CABLE: Optional shielded cable is available mating to the GFC
transducer 15-pin "D" connector.

4.1 CE Compliance

Any model GFC bearing a CE marking on it, is in compliance with the below
stated test standards currently accepted.

EMC Compliance with 89/336/EEC as amended;
Emission Standard: EN 55011:1991, Group 1, Class B
Immunity Standard: EN 55082-1:1992

7

FLOW RANGES

Table I GFC-110/111 Low Flow Mass Flow Controllers*

code scc/min [N2] code std liters/min [N2]

GFC-1101/2101
GFC-1102/2102

GFC-1103/2103
GFC-1104/2104

GFC-1105/2105 0 to 200
GFC-1106/2106 0 to 500

Table II GFC-113 Medium Flow Mass Flow Controllers*

0 to 10 GFC-1107/2107
0 to 20 GFC-1108/2108 0 to 2

0 to 50

GFC-1109/2109 0 to 5

0 to 100 GFC-1110/2110 0 to 10

0 to 1

code

GFC-1111/2111
GFC-1130/2130

std liters/min [N2]

0 to 15

20
GFC-1131/2131 30
GFC-1132/2132 40
GFC-1133/2133 50

Table III GFC-1142 High Flow Mass Flow Controllers*

code

std liters/min [N2]

GFC-1140/2140 60
GFC-1141/2141 80
GFC-1142/2142 100

*Flow rates are stated for Nitrogen at STP conditions [i.e. 700F (21.10C) at 1 atm].

For other gases use the K factor as a multiplier from APPENDIX 2.

8

TABLE IV PRESSURE DROPS

MODEL

GFC-110/GFC-111 UP to 10 720 1.06 75

GFC 113

GFC 114

FLOW RATE

[std liters/min]

15 2630 3.87 266
20 1360 2.00 138

30 2380 3.50 241
40 3740 5.50 379

50 5440 8.00 551

60 7480 11.00 758
100 12850 18.89 1302
200 7031 10.00 690
500 8437 12.00 827

1000 10547 15.00 1034

TABLE V APPROXIMATE WEIGHTS

model

GFC-110/ GFC-111
GFC-110/ GFC-111 Stainless
GFC-113, GFC-114
GFC-113, GFC-114 Stainless

5. OPERATING INSTRUCTIONS

1.9 lbs. (0.86 kg)

2.25 lbs. (1.02 kg)
2 lbs. (0.91 kg)

2.5 lbs. (1.13 kg)

MAXIMUM PRESSURE DROP

[mm H2O] [psid] [mbar]

weight shipping weight

3.4 lbs. (1.54 kg)

3.75 lbs. (1.70 kg)

3.50 lbs. (1.59 kg)
4 lbs. (1.81 kg)

5.1 Preparation and Warm Up

It is assumed that the Mass Flow Controller has been correctly installed and thor­oughly leak tested as described in section (2). Make sure the flow source is OFF.
Apply power to the unit via the 15-pin "D" connector. Make certain that you are
using a power supply that is between +12 and +15 VDC with at least 800 mA cur­rent capacity (or optionally, for models GFC110/111/113/114 only, +24 VDC 650
mA). Allow the Mass Flow Controller to warm-up for a minimum of 15 minutes.

During initial powering of the GFC transducer, the flow output signal will be indi­cating a higher than usual output. This is indication that the GFC transducer has
not yet attained it's minimum operating temperature. This condition will automat­ically cancel within a few minutes and the transducer should eventually zero.

If after the 15 minutes warm-up period, the display still indicates a reading of less
than ± 3.0 % of F.S., readjust the ZERO potentiometer [R34] through the access
window. Before zero adjustment it is good practice to temporarily disconnect the
gas source, to ensure that no seepage or leak occurs in to the meter.

If after the 15 minutes warm-up period, the display indicates a reading



of more than ±3.0 % of F.S., the unit has to be returned to the factory for repair.

9

CAUTION: If the valve is left in the AUTO (control) or OPEN (PURGE)
mode for an extended period of time, it may become warm or even hot



to the touch. Use care in avoiding direct contact with the valve during
operation.

Do not run GFC-110/111/113/114 for extended periods of time with the valve in
AUTO or PURGE mode without the flow of gas through the transducer. Doing so
may result in up to 2% f.s. shift in calibration.

5.2 Flow Signal Output Readings

The flow signal output can be viewed either on the LCD display, remote panel
meter, digital multimeter, or other display device used as shown in figure 2.a.

If an LCD display has been ordered with the GFC, the observed reading is in
direct engineering units. Such as 0 to 10 sccm or 0 to 100 slpm (0 to 100% indi­cation is optional). Engineering units are shown on the flow transducer's front
label.

Analog output flow signals of 0 to 5 VDC and 4 to 20 mA are attained at the appro­priate pins of the 15-pin "D" connector (see Figure 2-a) on the side of the GFC
transducer.

Meter signal output is linearly proportional to the mass molecular flow rate of the
gas being metered. The full scale range and gas for which your meter has been
calibrated are shown on the flow transducer's front label.

The default calibration is performed for 0 to 5 VDC input/output signal. If 4-20
mA output signal is used for flow indication on the GFC, which was calibrated
against 0 to 5 VDC input signal, the accuracy of the actual flow rate will be in the
specified range (+
ing may be in the range of +2.5% of full scale. Optional calibration for 4-20 mA
output signal is available upon request at time of order.

For optional RS232 or IEEE488 interfaces please contact your distributor or
Dwyer.

5.3 Swamping Condition

If a flow of more than 10% above the maximum flow rate of the Mass Flow
Controller is taking place, a condition known as "swamping" may occur. Readings
of a "swamped" meter cannot be assumed to be either accurate or linear. Flow
must be restored to below 110% of maximum meter range. Once flow rates are
lowered to within calibrated range, the swamping condition will end. Operation of
the meter above 110% of maximum calibrated flow may increase recovery time.

1.5%) of full scale, but the total uncertainty of the output read-

10

5.4 Setpoint Reference Signal

GFC flow controllers have a built-in solenoid valve (GFC-110/111/113/114) or
motorized valve (GFC-1143/1144/1145) and allow the user to set the flow to any
desired flow rate within the range of the particular model installed. The solenoid
valve is normally closed when no power is applied.

The motorized valve can be in any position depending on the operation mode of
the GFC during disconnecting of the power. For example if the motorized valve
was left in the OPEN purge position after disconnecting power from the GFC it will
be in the OPEN position. It is the customers responsibility to provide a solution to
shut down the flow in case of a power outage. When power is applied for the
GFC-1143/1144/1145 the valve automatically closes within the first ten seconds
regardless of the set point and valve override signals.

The setpoint is controlled either locally or remotely. The setpoint input responds to
an analog 0 to 5 VDC or 4 to 20 mA reference voltage (default jumper setting is 0
to 5 VDC). This voltage is a linear representation of 0 to 100% of the full scale
mass flow rate. Response time to setpoint changes are 1 second (GFC17), 2 sec­onds (GFC37/47) and 5 seconds (GFC-1143/1144/1145) within 2% of the final
flow over 25 to 100% of full scale.

For LOCAL flow control, use the built-in setpoint potentiometer located on the
same side as the solenoid valve of the GFC transducer. While applying flow to
the transducer, adjust the setpoint with an insulated screwdriver until the flow
reading is the same as the desired control point. [The display will only show the
actual instantaneous flow rate. There is no separate display for setpoint.]

For REMOTE control of the GFC, an analog reference signal must be supplied.
On pin 11 of the GFC transducer is a regulated and constant +5VDC output sig­nal. This signal may be used in conjunction with a local setpoint potentiometer for
flow setting.

FIGURE 5-A LOCAL SETPOINT POTENTIOMETER CONNECTIONS

It is recommended that a potentiometer between 5K to 100K ohm and capable of
at least 10-turns or more for adjustment be used. Use the control potentiometer
to command the percentage of flow desired.

11

Alternatively, a variable 0 to 5VDC or 4 to 20 mA analog signal may be applied
directly to the SETPOINT and COMMON connections of the GFC transducer (see
Figure 2-a). Be sure to apply the appropriate signal for the designated jumper set­tings.

5.5 Valve OFF Control (Open Collector NPN Compatible)

It may be necessary or desirable to set the flow and maintain that setting while
being able to turn the flow control valve off and on again. Closing of the valve
(without changing the setpoint adjustment) can be accomplished by connecting
pin 12 of the 15-pin "D" connector to COMMON (or power ground). When pin 12
is connected to COMMON, the solenoid valve is not powered and therefore will
remain normally closed regardless of the setpoint. The Motorized valve will be
given the command to close indicated by a green light on top of the unit).

Conversely, when the connection is left open or pin 12 remains unconnected the
valve remains active. The valve will remain active when the VALVE OFF pin
remains "floating". This feature is compatible with open collector NPN transistor
switches, as found in DC output ports of programmable controllers and similar
devices.

The simplest means for utilizing the VALVE OFF control feature, is to connect a
toggle switch between the COMMON and VALVE OFF pins of the GFC transduc­er.Toggling the switch on and off will allow for activating and deactivating the sole­noid valve.

12

5.6 Valve Test/Purge

At times, it may be necessary to purge the flow system with a neutralizing gas
such as pure dry nitrogen. The GFC transducer is capable of a full open condition
for the valve, regardless of setpoint conditions. Connecting the OPEN (PURGE)
pin (pin 4 on 15-pin "D" connector) to ground will fully open the valve.

The Motorized Valve: Connect pins 3 and 4 to OPEN the motorized control valve
A red light on top of the valve will indicated an OPEN valve condition, normal for
flow conditions.

Please Note: The valve stays OPEN even if power is no longer applied.



To CLOSE the Motorized Control Valve, connect pins 3 and 12.

6. MAINTENANCE

6.1 Introduction

It is important that the Mass Flow Controller/Controller is used with clean, filtered
gases only. Liquids may not be metered. Since the RTD sensor consists, in part,
of a small capillary stainless steel tube, it is prone to occlusion due to impedi­ments or gas crystallization. Other flow passages are also easily obstructed.
Therefore, great care must be exercised to avoid the introduction of any potential
flow impediment. To protect the instrument a 50 micron (GFC17) or 60 micron
(GFC-113/114) filter is built into the inlet of the flow transducer. The filter screen
and the flow paths may require occasional cleaning as described below. There is
no other recommended maintenance required. It is good practice, however, to
keep the meter away from vibration, hot or corrosive environments and excessive
RF or magnetic interference.

If periodic calibrations are required they should be performed by qualified per­sonnel and calibrating instruments, as described in section (7). It is recommend­ed that units are returned to Dwyer for repair service and calibration.

CAUTION: TO PROTECT SERVICING PERSONNEL IT IS MANDATO­RY THAT ANY INSTRUMENT BEING SERVICED IS COMPLETELY



PURGED AND NEUTRALIZED OF TOXIC, BACTERIOLOGICALLY
INFECTED, CORROSIVE OR RADIOACTIVE CONTENTS.

6.2 Flow Path Cleaning

Inspect visually the flow paths at the inlet and outlet ends of the meter for any
debris that may be clogging the flow through the meter. Remove debris carefully
using tweezers and blowing low pressure clean air or Nitrogen from the inlet side.
If the flow path is not unclogged, please return meter to Dwyer for servicing.

Do not attempt to disassemble the sensor. Disassembly will invalidate



calibration.

13

6.2.1 Cleaning the Inlet Filter Screen in GFC-110/111 Models

Unscrew the inlet compression fitting of meter. Note that the Restrictor Flow
Element (RFE) is connected to the inlet fitting.

The Restrictor Flow Element (RFE) is a precision flow divider inside the trans­ducer, which splits the inlet gas flow by a preset amount to the sensor and main
flow paths. The particular RFE used in a given Mass Flow Controller depends on
the gas and flow range of the instrument

Carefully disassemble the RFE from the inlet connection. The 50 micron filter
screen will now become visible. Push the screen out through the inlet fitting. Clean
or replace each of the removed parts as necessary. If alcohol is used for clean­ing, allow time for drying before re-assembling.

Inspect the flow path inside the transducer for any visible signs of contaminants.
If necessary, flush the flow path through with alcohol. Thoroughly dry the flow
paths by flowing clean dry gas through.

Carefully re-install the RFE and inlet fitting, avoiding any twisting and deforming
the RFE. Be sure that no dust has collected on the O-ring seal.

Note: Over tightening will deform and render the RFE defective.



It is advisable that at least one calibration point be checked after re installing the
inlet fitting - see section (7).

6.2.2 Cleaning the inlet Filter screen in GFC-113/114 Models

Unscrew the four socket head cap screws (two 10-24 and two 6-32) at the inlet
side of the meter. This will release the short square block containing the inlet
compression fitting.

The 60 micron filter screen will now become visible. Remove the screen DO NOT
remove the RFE inside the flow transducer! Clean or replace each of the removed
parts as necessary. If alcohol is used for cleaning, allow time for drying.

Inspect the flow path inside the transducer for any visible signs of contaminants.
If necessary, flush the flow path through with alcohol. Thoroughly dry the flow
paths by flowing clean dry gas through.

Re-install the inlet parts and filter screen. Be sure that no dust has collected on
the O-ring seal.

It is not recommended to attempt to disassemble, or repair GFC-113,
GFC-114, GFC-1143, GFC-1144 and GFC-1145 models.



Disassembly necessitates re-calibration.

14

6.2.3 Valve Maintenance for GFC-110/111/113/114 Models

The solenoid valve consists of 316 and 416 stainless steel, and VITON®(or
optional NEOPRENE®or KALREZ®) O rings and seals. No regular maintenance
is required except for periodic cleaning.

It is advisable that at least one calibration point be checked after re-installing the
inlet fitting - see section (7).

ADJUST. SCREW

O-RING

NUT

GUARD
ASSEMBLY

4-40 SOCKET
SCREW

VALVE BODY

FIGURE 6-a SOLENOID VALVE

COMPRESSION
SPRING

SPIRAL SPRING

CORE

SPIDER SPRING

STEM

SEAT-VITON
INSERT

O-RING

ORIFICE

O-RING

BLOCK

05-19-2006

Various corrosive gases may demand more frequent replacement of VITON

®

O-rings and seals inside the valve. Be sure to use an elastomer material, appro­priate for your specific gas application. Contact your distributor or Dwyer for
optional sealing materials available.

15

7. CALIBRATION PROCEDURES

NOTE: Removal of the factory installed calibration seals and/or any
adjustments made to the meter, as described in this section, will void



any calibration warranty applicable.

7.1 Flow Calibration

Dwyer Instruments' Flow Calibration Laboratory offers professional calibration
support for mass flow meters and Controllers, using precision calibrators under
strictly controlled conditions. NIST traceable calibrations are available.
Calibrations can also be performed at customers' site using available standards.

Factory calibrations are performed using NIST traceable precision volumetric cal­ibrators incorporating liquid sealed frictionless actuators.

Generally, calibrations are performed using dry nitrogen gas. The calibration can
then be corrected to the appropriate gas desired based on relative correction [K]
factors shown in the gas factor table - see Appendix 2. A reference gas, other than
nitrogen, may be used to closer approximate the flow characteristics of certain
gases. This practice is recommended when a reference gas is found with ther­modynamic properties similar to the actual gas under consideration. The appro­priate relative correction factor should be recalculated - see section (9).

It is standard practice to calibrate mass flow meters/controllers with dry nitrogen
gas at 70
sure and 0 psig (0 bar) outlet pressure. It is best to calibrate the GFC transducers
to actual operating conditions. Specific gas calibrations of non-toxic and non-cor­rosive gases are available at specific conditions. Please contact your distributor or
Dwyer for a price quotation.

It is recommended that a flow calibrator of at least four times better collective
accuracy than that of the mass flow meter/controller to be calibrated be used.
Equipment required for calibration includes a flow calibration standard and a cer­tified high sensitivity multimeter (which together have a collective accuracy of
±0.25% or better), an insulated (plastic) screwdriver, a flow regulator (example:
metering needle valve) installed upstream from the Mass Flow Controller and a
pressure regulated source of dry filtered nitrogen gas (or other suitable reference
gas).

The gas and ambient temperature, as well as inlet and outlet pressure conditions
should be set up in accordance with actual operating conditions.

0

F (21.10C), 20 psig (1.4 bars) [25 psig (1.7 bars) for GFC47] inlet pres-

16

CALIBRATION POTENTIOMETER LOCATIONS ARE ILLUSTRATED IN FIGURE 9A.

FIGURE 7-a CALIBRATION POTENTIOMETER AND JUMPER LOCATIONS (BACK OF GFC)

7.2 Calibration of GFC Mass Flow Controllers

All adjustments in this section are made from the outside of the meter, there is no
need to disassemble any part of the instrument.

GFC Mass Flow Controllers may be field recalibrated/checked for the same range
they were originally factory calibrated for. When linearity adjustment is needed, or
flow range changes are being made proceed to step 7.3. Flow range changes may
require a different Restrictor Flow Element (RFE). Additionally, a different
Solenoid Valve Orifice may also be required (see Table VI). Consult your distribu­tor or Dwyer for more information.

7.2.1 Connections and Initial Warm Up

At the 15-pin "D" connector of the GFC transducer, connect the multimeter to out­put pins [1] and [2] for 0 to 5 VDC (or pins [9] and [14] for 4 to 20 mA) - (see Figure
2a).

When using a remote setpoint for flow control, the appropriate reference signal
should also be connected to the 15-pin "D" connector at pins [8] and [10] - (see
Figure 2a). Power up the Mass Flow Controller for at least 30 minutes prior to
commencing the calibration procedure.

17

7.2.2 ZERO Adjustment

Shut off the flow of gas into the Mass Flow Controller. To ensure that no seepage or
leak occurs into the meter, it is good practice to temporarily disconnect the gas source.

Using the multimeter and the insulated screwdriver, adjust the ZERO poten­tiometer [R34] through the access window for 0 VDC (or 4 mA respectively) at
zero flow.

7.2.3 SPAN Adjustment

Reconnect the gas source. Adjust the control setpoint to 100% of full scale flow.
Check the flow rate indicated against the flow calibrator. If the deviation is less
than ±10% of full scale reading, correct the SPAN potentiometer [R33] setting by
using the insulated screwdriver through the access window, to eliminate any devi­ation. If the deviation is larger than ±10% of full scale reading, a defective condi­tion may be present.

LIKELY REASONS FOR A MALFUNCTIONING SIGNAL MAY BE:

z Occluded or contaminated sensor tube.
z Leaking condition in the GFC transducer or the gas line and fittings.
z For gases other than nitrogen, recheck appropriate "K" factor from Gas Factor Table.
z Temperature and/or pressure correction errors.

See also section (8) TROUBLESHOOTING. If after attempting to remedy the above con­ditions, a malfunction still persists, return the meter for factory service, see section (1).

At this point the calibration is complete. However, it is advisable that several addi­tional points between 0 and 100%, such as 25%, 50%, and 75% flow be checked.
If discrepancies are found, proceed to step 7.3 for Linearity Adjustment.

7.3 Linearity Adjustment

All adjustments in this section are made from the outside of the meter, there is no
need to disassemble any part of the instrument.

7.3.1.1 Disable Solenoid Valve in GFC-110/111/113/114 Models

Set the valve into PURGE mode. This step essentially bypasses the flow control
properties of the transducer. The unit will now act as a mass flow meter.

7.3.1.2 Open Motorized Valve in GFC-1143/1144/1145 Models

Set the valve to PURGE mode by connecting pin 4 to pin 3 (ground), on 15pin
D-connector.

CAUTION: FOR GFC-110/111/113/114-If the valve is left in the AUTO
(control) or OPEN mode for an extended period of time, it may become



warm or even hot to the touch. Use care in avoiding direct contact with
the valve during operation.

18

7.3.2 Connections and Initial Warm Up

On the transducer, connect the multimeter to output pins [1] and [2] for 0 to 5 VDC
(or pins [9] and [14] for 4 to 20 mA) of the 15-pin "D" connector - (see Figure 2-a).

If calibration to a new flow range or different gas is being performed, it may be
necessary to remove any jumpers at J1A, J1B, and J1C before beginning lin­earizing procedure.

Power up the Mass Flow Controller for at least 30 minutes prior to commencing
the calibration procedure.

7.3.3 ZERO Adjustment

Shut off the flow of gas into the Mass Flow Controller. To ensure that no seepage
or leak occurs into the meter, it is good practice to temporarily disconnect the gas
source.

Using the multimeter and the insulated screwdriver, adjust the ZERO poten­tiometer [R34] through the access window for 0 VDC (or 4 mA respectively) at
zero flow.

7.3.4 25% Flow Adjustment

Reconnect the gas source. Using the flow regulator, adjust the flow rate to 25% of
full scale flow. Check the flow rate indicated against the flow calibrator. Adjust the
setting for potentiometer [R33] by using the insulated screwdriver through the
access window, until the output of the flow meter reads 1.25VDC ±63mV (or 8mA

±0.25mA).

Linearizer

Function

Decrease

Increase

7.3.5 50% Flow Adjustment

Using the flow regulator, increase the flow rate to 50% of full scale flow. Check the
flow rate indicated against the flow calibrator. The output of the flow meter should
read 2.50VDC ±63mV (or 12mA ±0.25mA). If the reading is outside of that range,
place the jumper at [J1A] as appropriate to increase or decrease the signal. Adjust
the setting for potentiometer [R38] by using the insulated screwdriver through the
access window, until reading is within specification.

J1A

(50%)

1 - 2
2 - 3

FIGURE 7B CALIBRATION POTENTIOMETER AND JUMPERS

J1B

(75%)

4 - 5
5 - 6

J1C

(100%)

7 - 8
8 - 9

19

7.3.6 75% Flow Adjustment

Using the flow regulator, increase the flow rate to 75% of full scale flow. Check the
flow rate indicated against the flow calibrator. The output of the flow meter should
read 3.75VDC ±63mV (or 16mA ±0.25mA). If the reading is outside of that range,
place the jumper at [J1B] as appropriate to increase or decrease the signal. Adjust
the setting for potentiometer [R39] by using the insulated screwdriver through the
access window, until reading is within specification.

7.3.7 100% Flow Adjustment

Using the flow regulator, increase the flow rate to 100% of full scale flow. Check
the flow rate indicated against the flow calibrator. The output of the flow meter
should read 5.00VDC ±63mV (or 20mA ±0.25mA). If the reading is outside of that
range, place the jumper at [J1C] as appropriate to increase or decrease the sig­nal. Adjust the setting for potentiometer [R40] by using the insulated screwdriver
through the access window, until reading is within specification.

Repeat steps 7.3.4 to 7.3.7 at least once more.

7.3.8.1 Valve Adjustment for GFC-110/111/113/114

Discontinue the PURGE mode (set valve for the closed position). Apply an inlet
pressure of 5 psig, and atmospheric pressure at the outlet. If a small flow occurs,
turn the set screw on top of the solenoid valve clockwise until the flow through the
GFC just stops

7.3.8.2 Valve Adjustment for GFC-1143/1144/1145

DO NOT adjust the motorized valve for GFC-1143/1144/1145.
The motorized valve for these models has been pre-adjusted at the factory.

7.3.9 Full Scale Flow Adjustment

Fully open the flow regulator upstream of the GFC. Increase the inlet pressure to
20 psig (25 psig for GFC-1145). Apply a +5.00 VDC (100% full scale flow) setpoint
reference. Using the calibrator check the flow rate. If necessary, adjust R33 to
match the desired full scale flow rate. [In control mode, turning R33 clockwise will
decrease the flow. Conversely, turning R33 counterclockwise will increase the flow
through the GFC.]

7.3.10 25% Flow Adjustment

Change the setpoint to 1.25 VDC to control at 25% of full scale flow. Check the
flow rate indicated against the flow calibrator. If the flow rate is not within ±0.75%
of full scale, re-adjust the setting for potentiometer [R33], until the flow output is
correct.

7.3.11 50% Flow Adjustment

Change the setpoint to 2.50 VDC to control at 50% of full scale flow. Check the
flow rate indicated against the flow calibrator. If the flow rate is not within ±0.75%
of full scale, re-adjust the setting for potentiometer [R38], until the flow output is
correct.

20

7.3.12 75% Flow Adjustment

Change the setpoint to 3.75 VDC to control at 75% of full scale flow. Check the
flow rate indicated against the flow calibrator. If the flow rate is not within ±0.75%
of full scale, re-adjust the setting for potentiometer [R39], until the flow output is
correct.

7.3.13 100% Flow Adjustment

Change the setpoint to 5.00 VDC to control at 100% of full scale flow. Check the
flow rate indicated against the flow calibrator. If the flow rate is not within ±0.75%
of full scale, re-adjust the setting for potentiometer [R40], until the flow output is
correct.

Repeat steps 7.3.10 to 7.3.13 at least once more.

TABLE VI GFC SOLENOID VALVE ORIFICE SELECTION TABLE

Orifice Part Number

OR.010
OR.020
OR.040
OR.055
OR.063
OR.073
OR.094
OR.125

7.4 LCD Display Scaling

It may be desirable to re-scale the output reading on the LCD readout supplied
with certain model GFC transducers. Re-calibration for a new flow range or dif­ferent engineering units are two examples of when this may be necessary.

7.4.1 Access LCD Display Circuit

Carefully remove the LCD from the GFC or panel mounted surface. Remove the
aluminum housing on the side of the connection cable. Slide the LCD assembly
out of the aluminum housing.

7.4.2 Adjust Scaling

Flow rate [ N2 ]

under 10 sccm

10 to 1000 sccm

1 to 5 slpm

5 to 10 slpm
10 to 15 slpm
15 to 20 slpm
20 to 50 slpm

50 to 100 slpm

Using a digital multimeter connected to either the 0 to 5 VDC or 4 to 20 mA sig­nal at the 15-pin "D" connector, set the flow rate on the GFC to full scale flow (5
VDC or 20mA). Maintain full scale flow, and adjust the potentiometer [R3] on the
LCD printed circuit board to desired full scale flow reading.

21

7.4.3 Change Decimal Point

To change the decimal place on the LCD display readout, simply move the jumper
to the appropriate location on the 8-pin header block. The numbers are printed to
the side of the connections. Do not attempt to place more than one jumper for
decimal setting.

JUMPER POSITION

"0"
"1"
"2"
"3"

8. TROUBLESHOOTING

8.1 Common Conditions

Your Mass Flow Controller/Controller was thoroughly checked at numerous qual­ity control points during and after manufacturing and assembly operations. It was
calibrated in accordance to your desired flow and pressure conditions for a given
gas or a mixture of gases.

It was carefully packed to prevent damage during shipment. Should you feel that
the instrument is not functioning properly please check for the following common
conditions first:

Are all cables connected correctly?

Are there any leaks in the installation?

Is the power supply correctly selected according to requirements? When
several meters are used a power supply with appropriate current rating
should be selected.

MAXIMUM SCALABLE DISPLAY READING

1999

199.9

19.99

1.999

Were the connector pinouts matched properly? When interchanging with
other manufacturers' equipment, cables and connectors must be carefully
wired for correct pin configurations.

Is the pressure differential across the instrument sufficient?

22

8.2 Troubleshooting Guide

INDICATION LIKELY REASON REMEDY

lack of reading power supply off check connection of power supply
or output

fuse blown disconnect transducer from

power supply; remove the
shorting condition or check
polarities; fuse resets
automatically

filter screen flush clean or disassemble to
obstructed at inlet remove impediments or replace

occluded sensor tube flush clean or disassemble to

remove impediments or return to
factory for replacement

pc board defect return to factory for replacement

valve adjustment wrong re-adjust valve (section 7.3)

flow reading inadequate gas pressure apply appropriate gas pressure
does not
coincide with filter screen obstructed flush clean or disassemble to
the setpoint at inlet remove impediments or replace

ground loop signal and power supply

commons are different

no response inadequate gas pressure apply appropriate gas pressure
to setpoint

cable or connector malfunction check cables and all connections

or replace

setpoint is too low re adjust setpoint or disable 2%
(<2% of full scale) cutoff feature (section 2.2)

valve adjustment wrong re-adjust valve (section 7.3)

unstable or gas leak locate and correct
no zero reading

pc board defective return to factory for replacement

full scale output defective sensor return to factory for replacement
at "no flow"
condition or
with valve gas leak locate and repair
closed

23

INDICATION LIKELY REASON REMEDY

calibration off gas metered is not the same as use matched calibration

what meter was calibrated for

composition of gas changed see K factor tables in APPENDIX 2

gas leak locate and correct

pc board defective return to factory for replacement

RFE dirty flush clean or disassemble to

remove impediments

occluded sensor tube flush clean or disassemble to

remove impediments or return to
factory for replacement

filter screen obstructed flush clean or disassemble to
at inlet remove impediments or replace

transducer is not check for any tilt or change in the
mounted properly mounting of the transducer;

generally, units are calibrated for
horizontal installation
(relative to the sensor tube)

GFC valve does incorrect valve adjustment re-adjust valve (section 7.3)
not work
in open position

pc board defect return to factory for replacement

cable or connectors check cable and connectors
malfunction or replace

differential pressure too high decrease pressure to correct level

insufficient inlet pressure adjust appropriately

GFC valve does incorrect valve adjustment re-adjust valve (section 7.3)
not work in
closed position pc board defect return to factory for replacement

cable or connectors check cable and connectors
malfunction or replace

orifice obstructed disassemble to remove

impediments or return to factory

24

For best results it is recommended that instruments are returned to the factory for
servicing. See section 1.3 for return procedures.

8.3 Technical Assistance

Dwyer Instruments will provide technical assistance over the phone to qualified
repair personnel. Please call our Technical Assistance at (219)-879-8000. Please
have your Serial Number and Model Number ready when you call.

9. CALIBRATION CONVERSIONS FROM REFERENCE GASES

The calibration conversion incorporates the K factor. The K factor is derived from
gas density and coefficient of specific heat. For diatomic gases:

gas

d X C

p

1

=

K

where d = gas density (gram/liter)
C

= coefficient of specific heat (cal/gram)

p

Note: In the above relationship that d and Cp are usually chosen at the same
conditions (standard, normal or other).

If the flow range of a Mass Flow Controller remains unchanged, a relative K fac­tor is used to relate the calibration of the actual gas to the reference gas.

Q

a

=

K

Q

r

K

a

=

K

r

where Qa= mass flow rate of an actual gas (sccm)
Q

r

K

a

K

r

= mass flow rate of a reference gas (sccm)
= K factor of an actual gas
= K factor of a reference gas

For example, if we want to know the flow rate of oxygen and wish to calibrate
with nitrogen at 1000 SCCM, the flow rate of oxygen is:

QO2= Qa= QrX K = 1000 X 0.9926 = 992.6 sccm

where K = relative K factor to reference gas (oxygen to nitrogen)

25

APPENDIX 1

COMPONENTS DIAGRAM

GFC METERING PC BOARD (TOP SIDE)

26

COMPONENTS DIAGRAM

GFC METERING PC BOARD (BOTTOM SIDE)

27

APPENDIX 2

GAS FACTOR TABLE (“K” FACTORS)

Actual Gas

AcetyleneC

2H2

Air
Allene (Propadiene) C
Ammonia NH

3H4

3

Argon Ar
Arsine AsH
Boron Trichloride BCl
Boron Trifluoride BF
Bromine Br
Boron Tribromide Br
Bromine Pentaflouride BrF
Bromine Trifluoride BrF

3

3

3

2

3

5

3

Bromotrifluoromethane (Freon-13 B1) CBrF
1,3-Butadiene C4H
Butane C4H
1-Butane C4H

6

10

8

2-Butane C4H8CIS
2-Butane C
Carbon Dioxide CO
Carbon Disulfide CS
Carbon Monoxide C
Carbon Tetrachloride CCl
Carbon Tetrafluoride (Freon-14)CF
Carbonyl Fluoride COF

4H8

TRANS

2

2

O

4

4

2

Carbonyl Sulfide COS
Chlorine Cl
Chlorine Trifluoride ClF
Chlorodifluoromethane (Freon-22)CHClF
Chloroform CHCl

2

3

2

3

Chloropentafluoroethane(Freon-115)C2ClF
Chlorotrifluromethane (Freon-13) CClF
CyanogenC2N

2

3

CyanogenChloride CICN
Cyclopropane C
Deuterium D
Diborane B2H

3H5

2

6

3

5

K Factor

Relative to N

.5829

1.0000
.4346
.7310

1.4573
.6735
.4089
.5082
.8083
.38
.26
.3855
.3697
.3224
.2631
.2994
.324
.291
.7382
.6026

1.00
.31
.42
.5428
.6606
.86
.4016
.4589
.3912
.2418
.3834
.61
.6130
.4584

1.00
.4357

Cp

[Cal/g]

2

.4036
.240
.352
.492
.1244
.1167
.1279
.1778
.0539
.0647
.1369
.1161
.1113
.3514
.4007
.3648
.336
.374
.2016
.1428
.2488
.1655
.1654
.1710
.1651
.114
.1650
.1544
.1309
.164
.153
.2613
.1739
.3177

1.722
.508

Density

[g/I]

1.162

1.293

1.787
.760

1.782

3.478

5.227

3.025

7.130

11.18

7.803

6.108

6.644

2.413

2.593

2.503

2.503

2.503

1.964

3.397

1.250

6.860

3.926

2.945

2.680

3.163

4.125

3.858

5.326

6.892

4.660

2.322

2.742

1.877

1.799

1.235

28

Actual Gas

K Factor

Relative to N

Cp

[Cal/g]

2

Density

[g/I]

Dibromodifluoromethane CBr2F

2

Dichlorodifluoromethane (Freon-12) CCl2F
Dichlofluoromethane (Freon-21) CHCl2F
Dichloromethylsilane (CH
Dichlorosilane SiH2Cl

SiCl

3)2

2

2

Dichlorotetrafluoroethane (Freon-114) C2Cl2F
1,1-Difluoroethylene (Freon-1132A) C2H2F
Dimethylamine (CH3)2NH
Dimethyl Ether (CH
2,2-Dimethylpropane C
Ethane C2H

6

3)2

O

3H12

Ethanol C2H6O
Ethyl Acetylene C

4H6

Ethyl Chloride C2H5Cl
Ethylene C

2H4

Ethylene Oxide C2H4O
Fluorine F
Fluoroform (Freon-23) CHF

2

3

Freon-11 CCl3F
Freon-12 CCl
Freon-13 CClF
Freon-13B1 CBrF
Freon-14 CF

2F2

3

3

4

Freon-21 CHCl2F
Freon-22 CHClF
Freon-113 CCl2FCClF
Freon-114 C2Cl2F
Freon-115 C2ClF
Freon-C318 C4F
Germane GeH
Germanium Tetrachloride GeCl

2

2

4

5

8

4

4

Helium He
Hexafluoroethane C
Hexane C
Hydrogen H

6H14

2

(Freon-116)

2F6

Hydrogen Bromide HBr
Hydrogen Chloride HCl
Hydrogen Cyanide HCN

.1947

2

.3538
.4252
.2522
.4044
.2235

4

.4271

2

.3714
.3896
.2170
.50
.3918
.3225
.3891
.60
.5191
.9784
.4967
.3287
.3538
.3834
.3697
.4210
.4252
.4589
.2031
.2240
.2418
.1760
.5696
.2668

1.454
.2421
.1792

1.0106

1.000

1.000

1.070

.15
.1432
.140
.1882
.150
.1604
.224
.366
.3414
.3914
.420
.3395
.3513
.244
.365
.268
.1873
.176
.1357
.1432
.153
.1113
.1654
.140
.1544
.161
.160
.164
.185
.1404
.1071

1.241
.1834
.3968

3.419
.0861
.1912
.3171

9.362

5.395

4.592

5.758

4.506

7.626

2.857

2.011

2.055

3.219

1.342

2.055

2.413

2.879

1.251

1.965

1.695

3.127

6.129

5.395

4.660

6.644

3.926

4.592

3.858

8.360

7.626

6.892

8.397

3.418

9.565
.1786

6.157

3.845
.0899

3.610

1.627

1.206

29

Actual Gas

Hydrogen Fluoride HF
Hydrogen Iodide HI
Hydrogen Selenide H
Hydrogen Sulfide H
Iodine Pentafluoride IF
Isobutane CH(CH3)
Isobutylene C4H

Se

2

S

2

5

3

6

Krypton Kr
Methane CH
Methanol CH
Methyl Acetylene C3H

4

3

4

Methyl Bromide CH2Br
Methyl Chloride CH
Methyl Fluoride CH
Methyl Mercaptan CH
Methyl Trichlorosilane (CH
Molybdenum Hexafluoride MoF
Monoethylamine C2H5NH
Monomethylamine CH3NH

Cl

3

F

3

SH

3

)SiCl

3

3

6

2

2

Neon NE
Nitric Oxide NO
Nitrogen N
Nitrogen Dioxide NO
Nitrogen Trifluoride NF

2

2

3

Nitrosyl Chloride NOCl
Nitrous Oxide N

O

2

Octafluorocyclobutane (Freon-C318) C
Oxygen O
Oxygen Difluoride OF

2

2

Ozone
Pentaborane B
Pentane C5H

5H9

12

Perchloryl Fluoride ClO3F
Perfluoropropane C
Phosgene COCl
Phosphine PH
Phosphorous Oxychloride POCl
Phosphorous Pentafluoride PH

3F8

2

3

3

5

4F8

K Factor

Relative to N

.9998
.9987

.7893

.80

.2492

.27
.2951

1.453
.7175
.5843
.4313
.5835
.6299
.68
.5180
.2499
.2126
.3512
.51

1.46
.990

1.000
.737
.4802
.6134
.7128
.176
.9926
.6337
.446
.2554
.2134
.3950
.174
.4438

1.070
.36
.3021

Cp

[Cal/g]

2

.3479
.0545

.1025

.2397
.1108
.3872
.3701
.0593
.5328
.3274
.3547
.1106
.1926
.3221
.2459
.164
.1373
.387
.4343
.246
.2328
.2485
.1933
.1797
.1632
.2088
.185
.2193
.1917
.195
.38
.398
.1514
.197
.1394
.2374
.1324
.1610

Density

[g/I]

.893

5.707

3.613

1.520

9.90

3.593

2.503

3.739
.715

1.429

1.787

4.236

2.253

1.518

2.146

6.669

9.366

2.011

1.386
.900

1.339

1.25

2.052

3.168

2.920

1.964

8.397

1.427

2.406

2.144

2.816

3.219

4.571

8.388

4.418

1.517

6.843

5.620

30

Actual Gas

Phosphorous Trichloride PCl
Propane C3H
Propylene C3H
Silane SiH

8

6

4

Silicon Tetrachloride SiCl
Silicon Tetrafluoride SiF
Sulfur Dioxide SO

2

Sulfur Hexafluoride SF
Sulfuryl Fluoride SO2F

3

4

4

6

2

Tetrafluoroethane (Forane 134A) CF3CH2F
Tetrafluorohydrazine N

2F4

Trichlorofluoromethane (Freon-11) CCl3F
Trichlorosilane SiHCl

3

1,1,2-Trichloro-1,2,2 Trifluoroethane
(Freon-113) CCl

FCClF

2

2

Triisobutyl Aluminum (C4H9)AL
Titanium Tetrachloride TiCl
Trichloro Ethylene C2HCl

4

3

Trimethylamine (CH3)3N
Tungsten Hexafluoride WF
Uranium Hexafluoride UF

6

6

Vinyl Bromide CH2CHBr
Vinyl Chloride CH

CHCl

2

Xenon Xe

K Factor

Relative to N

.30
.35
.40
.5982
.284
.3482
.69
.2635
.3883
.5096
.3237
.3287
.3278

.2031

.0608
.2691
.32
.2792
.2541
.1961
.4616
.48

1.44

Cp

[Cal/g]

2

.1250
.399
.366
.3189
.1270
.1691
.1488
.1592
.1543
.127
.182
.1357
.1380

.161

.508
.120
.163
.3710
.0810
.0888
.1241
.12054
.0378

Density

[g/I]

6.127

1.967

1.877

1.433

7.580

4.643

2.858

6.516

4.562

4.224

4.64

6.129

6.043

8.36

8.848

8.465

5.95

2.639

13.28

15.70

4.772

2.788

5.858

31

APPENDIX 3

DIMENSIONAL DRAWINGS

GFC-110/GFC-111 MASS FLOW CONTROLLER

NOTE: Dwyer reserves the right to change designs and dimensions at its sole discretion at
any time without notice. For certified dimensions please contact Dwyer.

32

GFC-113/GFC-114 MASS FLOW CONTROLLER

NOTE: Dwyer reserves the right to change designs and dimensions at its sole discretion

at any time without notice. For certified dimensions please contact Dwyer.

33

GFC-1143 MASS FLOW CONTROLLER

GFC-1144 MASS FLOW CONTROLLER

34

GFC-1145 MASS FLOW CONTROLLER

NOTE: Dwyer reserves the right to change designs and dimensions at its sole discretion

at any time without notice. For certified dimensions please contact Dwyer.

35

APPENDIX 4

WARRANTY

Dwyer Mass Flow Systems are warranted against parts and
workmanship for a period of one year from the date of purchase.
Calibrations are warranted for up to six months after date of pur­chase, provided calibration seals have not been tampered with. It is
assumed that equipment selected by the customer is constructed of
materials compatible with gases used. Proper selection is the
responsibility of the customer. It is understood that gases under pres­sure present inherent hazards to the user and to equipment, and it is
deemed the responsibility of the customer that only operators with
basic knowledge of the equipment and its limitations are permitted to
control and operate the equipment covered by this warranty. Anything
to the contrary will automatically void the liability of Dwyer and the
provisions of this warranty. Defective products will be repaired or
replaced solely at the discretion of Dwyer at no charge. Shipping
charges are borne by the customer.This warranty is void if the equip­ment is damaged by accident or misuse, or has been repaired or
modified by anyone other than Dwyer or factory authorized service
facility. This warranty defines the obligation of Dwyer and no other
warranties expressed or implied are recognized.

NOTE: Follow Return Procedures In Section 1.3.

TRADEMARKS

Buna®-is a registered trademark of DuPont Dow Elastometers.
Dwyer®-is a registered trademark of Dwyer Instruments.

®

-is a registered trademark of DuPont Dow Elastomers.

Kalrez

®

Neoprene

-is a registered trademark of DuPont.

Swagelok VCR®-is a registered trademark of Swagelok Marketing Co.
Viton®-is a registered trademark of Dupont Dow Elastomers L.L.C.

36