SMC Networks PFCQ531 Series User manual

Doc. no. DOC1048409
PRODUCT NAME
Flow Controller for Air
MODEL / Series / Product Number
PFCQ531 Series

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Contents
1 Product Outline and Features .......................................................................3
2 Safety Instructions ..........................................................................................4
3 Items Included in the Package......................................................................6
4 Names and Functions of Product Parts......................................................7
5 How to Order ....................................................................................................8
6 Specifications...................................................................................................9
6-1 General specifications ...........................................................................9
6-2 Electrical specifications.......................................................................10
6-3 Functional characteristics...................................................................11
(1) Analog input (flow rate command signal) ...............................................11
(2) Analog output (flow rate output signal)...................................................11
(3) Controllable range .................................................................................11
(4) IN side straight pipe length and accuracy (reference value)...................12
7 Dimensions .....................................................................................................13
8 Component Drawing of Parts in Contact with Fluid and Parts Names……….15
9 Working Principle.............................................................................................16
10 Installation.....................................................................................................17
10-1 Installation ............................................................................................17
10-2 Air supply..............................................................................................19
10-3 Piping.....................................................................................................20
10-4 Electrical Connection .........................................................................22
(1) D-sub connector terminal No. ................................................................22
(2) Example of D-sub connector wiring .......................................................23
(3) Flow rate display connector terminal No. ...............................................25
(4) the flow rate display connector and the digital flow monitor ...................25
11 Operation.......................................................................................................26
11-1 Types of operation...............................................................................26
11-2 Analog input operation.......................................................................27
11-3 Valve fully open operation .................................................................30
12 Options ..........................................................................................................32
12-1 Power supply cables ..........................................................................32
12-2 Brackets ................................................................................................33
12-3 Digital flow monitor.............................................................................34
13 Separately Sold Products ..........................................................................37
13-1 Digital flow monitor mounting bracket ...........................................37

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14 Maintenance..................................................................................................39
14-1 Maintenance and Inspection .............................................................39
14-2 Troubleshooting ..................................................................................40
(1) Operation problems ...............................................................................40
(2) Flow rate control problems ....................................................................41
(3) Output signal problems..........................................................................45
(4) Flow rate display problem......................................................................46
14-3 LED indication and error measures ................................................47
15 Handling Precautions .................................................................................50
15-1 Design and selection precautions ...................................................50
15-2 Handling precautions .........................................................................51
15-3 Mounting ...............................................................................................53
15-4 Power supply .......................................................................................54
15-5 Grounding.............................................................................................55
15-6 Wiring.....................................................................................................55
15-7 Operating environment ......................................................................57
15-8 Maintenance .........................................................................................58

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1. Product Outline and Features
This product controls the flow rate of air and nitrogen gas according to the analog signal (voltage
signal 1 to 5 V or current signal 4 to 20 mA) that is input from an external device such as a PLC. The
following describes the main characteristics and functions of this product.
(1) Maximum controlled flow rate: 300 L/min
Note: Flow rate converted to volume at 0 oC and 1 atm (atmospheric pressure).
(2) Wide operational differential pressure range: 0.05 to 0.5 MPa
(3) High speed response: 0.5 sec maximum
Note: The time when an operational differential pressure of 0.3 MPa, temperature of 25 oC, power
supply voltage of 24 V, command flow rate of a step signal from 3% to 100% is input, the
flow rate is set within +/-3% F.S. of the command flow rate.
(4) Compact size 130 (L) x 31 (W) x 130 (H) (w/o including the connector); lightweight 850 g (body
only)
(5) Non-grease assembly
(6) Flow rate control accuracy: Within 3% F.S.
(7) A flow rate detected by the built-in flow sensor is output to an external device with an analog
signal (voltage signal of 1 to 5 V; current signal of 4 to 20 mA)
(8) The current flow rate is displayed on the connected digital flow monitor (PFG310)
(9) Improved noise immunity by isolating the digital circuit from the power supply circuit and analog
circuit
(10) 24 VDC drive
(11) No dust generated from the spring seat because no spring is used

2. Safety Instructions
Safety Instructions
These safety instructions are intended to prevent hazardous situations and/or equipment damage.
These instructions indicate the level of potential hazard with the labels of “Caution,” “Warning” or “Danger.”
They are all important notes for safety and must be followed in addition to International Standards
(ISO/IEC)*1) , and other safety regulations.
*1) ISO 4414: Pneumatic fluid power -- General rules relating to systems.
ISO 4413: Hydraulic fluid power -- General rules relating to systems.
IEC 60204-1: Safety of machinery -- Electrical equipment of machines .(Part 1: General requirements)
ISO 10218: Manipulating industrial robots -Safety.
etc.
Caution
Caution indicates a hazard with a low level of risk which, if not avoided, could result
in minor or moderate injury.
Warning
Warning indicates a hazard with a medium level of risk which, if not avoided, could
result in death or serious injury.
Danger
Danger indicates a hazard with a high level of risk which, if not avoided, will result
in death or serious injury.
Warning
1. The compatibility of the product is the responsibility of the person who designs the equipment or
decides its specifications.
Since the product specified here is used under various operating conditions, its compatibility with specific
equipment must be decided by the person who designs the equipment or decides its specifications based on
necessary analysis and test results.
The expected performance and safety assurance of the equipment will be the responsibility of the person who
has determined its compatibility with the product.
This person should also continuously review all specifications of the product referring to its latest catalog
information, with a view to giving due consideration to any possibility of equipment failure when configuring the
equipment.
2. Only personnel with appropriate training should operate machinery and equipment.
The product specified here may become unsafe if handled incorrectly.
The assembly, operation and maintenance of machines or equipment including our products must be
performed by an operator who is appropriately trained and experienced.
3. Do not service or attempt to remove product and machinery/equipment until safety is confirmed.
1.The inspection and maintenance of machinery/equipment should only be performed after measures to
prevent falling or runaway of the driven objects have been confirmed.
2.When the product is to be removed, confirm that the safety measures as mentioned above are implemented
and the power from any appropriate source is cut, and read and understand the specific product precautions
of all relevant products carefully.
3. Before machinery/equipment is restarted, take measures to prevent unexpected operation and malfunction.
4. Contact SMC beforehand and take special consideration of safety measures if the product is to
be used in any of the following conditions.
1. Conditions and environments outside of the given specifications, or use outdoors or in a place exposed to
direct sunlight.
2. Installation on equipment in conjunction with atomic energy, railways, air navigation, space, shipping,
vehicles, military, medical treatment, combustion and recreation, or equipment in contact with food and
beverages, emergency stop circuits, clutch and brake circuits in press applications, safety equipment or
other applications unsuitable for the standard specifications described in the product catalog.
3. An application which could have negative effects on people, property, or animals requiring special safety
analysis.
4.Use in an interlock circuit, which requires the provision of double interlock for possible failure by using a
mechanical protective function, and periodical checks to confirm proper operation.
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Safety Instructions
Caution
The product is provided for use in manufacturing industries.
The product herein described is basically provided for peaceful use in manufacturing industries.
If considering using the product in other industries, consult SMC beforehand and exchange
specifications or a contract if necessary.
If anything is unclear, contact your nearest sales branch.
Limited warranty and Disclaimer/Compliance Requirements
The product used is subject to the following “Limited warranty and Disclaimer” and “Compliance
Requirements”.
Read and accept them before using the product.
Limited warranty and Disclaimer
1.The warranty period of the product is 1 year in service or 1.5 years after the product is
delivered,whichever is first.2)
Also, the product may have specified durability, running distance or replacement parts. Please
consult your nearest sales branch.
2. For any failure or damage reported within the warranty period which is clearly our responsibility,
a replacement product or necessary parts will be provided.
This limited warranty applies only to our product independently, and not to any other damage
incurred due to the failure of the product.
3. Prior to using SMC products, please read and understand the warranty terms and disclaimers
noted in the specified catalog for the particular products.
2) Vacuum pads are excluded from this 1 year warranty.
A vacuum pad is a consumable part, so it is warranted for a year after it is delivered.
Also, even within the warranty period, the wear of a product due to the use of the vacuum
pad or failure due to the deterioration of rubber material are not covered by the limited
warranty.
Compliance Requirements
1. The use of SMC products with production equipment for the manufacture of weapons of mass
destruction(WMD) or any other weapon is strictly prohibited.
2. The exports of SMC products or technology from one country to another are governed by the
relevant security laws and regulation of the countries involved in the transaction. Prior to the
shipment of a SMC product to another country, assure that all local rules governing that export
are known and followed.
Caution
SMC products are not intended for use as instruments for legal metrology.
Measurement instruments that SMC manufactures or sells have not been qualified by type approval tests
relevant to the metrology (measurement) laws of each country.
Therefore, SMC products cannot be used for business or certification ordained by the metrology
(measurement) laws of each country.
! Caution
SMC products are not intended for use as instruments for legal metrology.
Measurement instruments that SMC manufactures or sells have not been qualified by type approval tests
relevant to the metrology (measurement) laws of each country.
Therefore, SMC products cannot be used for business or certification ordained by the metrology
(measurement) laws of each country.
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3. Items Included in the Package
● Options (The following items are included in the package depending on the model
selected for the flow controller for Air.)
Power supply cable (PFCQ531-H1-3)
Digital flow monitor (PFG310-XY-M-Y-X105)
Bracket (PFCQ531-B1)
(with 4 x hexagon socket head cap screws)
Lead wire with connector (ZS-33-D)
(for connection with the digital flow monitor)
Sensor connector (ZS-28-C-1)
(for connection with the digital flow monitor)
Flow controller for Air (body)
● Accessories
Protective plug
(PFCQP-910S-31)

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4. Names and Functions of Product Parts
Name
Function
Power supply (PWR)
LED
When 24 V power is supplied and the system starts the
operation, this LED turns ON and flashes.
Error (ERR) LED
This LED turns ON and flashes when fully open or when an
error occurs.
D-sub connector
(CN1)
This connector has connections for power supply, flow rate
command signal, switch input signal, flow rate output signal,
and switch output signal. For information on pin numbers and
functions, refer to “10-4. (1) D-sub connector terminal No.”.
Flow rate display
connector
(CN3)
This connector is for connecting to the digital flow monitor
PFG310 (optional) to display the flow rate.
When not using the digital flow monitor, mount the protective
plug on the connector.
Piping port
This port is a connection port for piping. The IN side is for inlet
and the OUT side is for outlet.
F.G.
Frame ground.
A grounding cable must be connected to the F.G.
*CN2: A communication connector (Scheduled to be included in the lineup separately.)
Power supply LED
Error LED
Flow rate display connector
(with protective plug)
Piping port (IN side)
Piping port (OUT side)
D-sub connector
Protective plug
F.G.

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5. How to Order
○ Input/Output specification table
Symbol
IN1
INA
OUT1
OUTA
A1
Common for NPN
and PNP
Analog 1 to 5 V
NPN
Analog 1 to 5 V
A2
Common for NPN
and PNP
Analog 4 to 20 mA
NPN
Analog 4 to 20 mA
A3
Common for NPN
and PNP
Analog 1 to 5 V
PNP
Analog 1 to 5 V
A4
Common for NPN
and PNP
Analog 4 to 20 mA
PNP
Analog 4 to 20 mA
Flow controller
(Display separate type)
Rated flow range (flow rate range)
31
9 to 300L/min
Port size
04
Rc1/2
Input/Output specifications
(See the Input/Output Specification Table.)
PFCQ5 31 – 04 - A1 C - S M
Option 1 (Power supply cable)
Nil
None
C
Power supply cable (3 m)
Option 2 (Bracket)
Nil
None
S
Bracket
Option 3 (Digital flow monitor)
Nil
None
M
Digital flow monitor
When this option is selected, the following items are shipped
together with the product.
- Display: Digital flow monitor
PFG310-XY-M-Y-X105
- Lead wire: Lead wire with connector (2 m)
ZS-33-D
- Connector: Sensor connector
ZS-28-C-1
The Operation Manual and certificate for the digital flow monitor
are not included in the package. If you need them, please place
an order separately.
Note: Optional parts are not
mounted to the product.
They are shipped together
with the product.
Provided with 4 x hexagon socket
head cap screws

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6. Specifications
6-1. General specifications
Model
PFCQ531-04-A*
Fluid
Applicable fluid
Dry air, N2
(Air quality classes: JIS B8392-1 1.1.2 to 1.6.2;
ISO8573-1 1.1.2 to 1.6.2*1)
Flow rate
specifications
*2, *3
Detection type
Hot wire anemometer
Rated controlled flow
rate range*4
9 to 300 L/min
Set controlled flow rate
range*5
3 to 300 L/min
Pressure
specifications
Standard operational
differential pressure
300 kPa
Operational differential
pressure range*6
50 to 500 kPa
Operating pressure
range*7
50 to 800 kPa
Withstand pressure
1.0 MPa
Mounting orientation
Downward orientation not allowed
External leakage
10 cm3/min or less
Environmental
resistance
Protection class
IP40
Withstand voltage
1000 VAC for 1 minute, between terminals and housing
Insulation resistance
50 MΩ or more between terminals and housing (with
500 VDC megger)
Operating temperature
range
Operation: 5 to 45oC (Guaranteed accuracy: 15 to 35
oC)
Storage: -10 to 60 oC (No condensation or freezing)
Operating humidity
range
Operation and storage: 35 to 85 %RH (No
condensation)
Standards
CE, UKCA, RoHS
Piping port
Rc1/2
Main materials of parts in contact with
fluid
PPS, FKM, SUS303, SUS304, SUS316, electroless
nickel plating, Si, Au, GE4F, DLC
Weight
Body
850 g
Power supply cable
210 g
Bracket
30 g
*1: Refer to “Examples of recommended pneumatic circuits” described in “10-2. Air supply”.
*2: Flow rate converted to volume at 0oC and 1 atm (atmospheric pressure).
*3: For the relationship between the operational differential pressure and the controllable flow rate, refer
to “6-3. Functional characteristics (3) Controllable range”.
*4: The accuracy may not be satisfied outside of the rated controlled flow range because the flow rate
control is unstable.
*5: The set controlled flow rate range is the settable flow rate range.
*6: The operational differential pressure range is the differential pressure required for this product to
operate normally.
*7: The operating pressure range is the pressure range that can be applied to the primary side (IN side)
of the product.

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6-2. Electrical specifications
Model
PFCQ531-04-A*
Power supply
specifications
Power supply voltage
Main power supply: 24 VDC +/-10%
Signal power supply: 24 VDC +/-10%
Current consumption
Main power supply: 0.5 A or less
Signal power supply: 0.05 A or less
Protection
Polarity protection
Control
specifications
Valve driving actuator
Linear motor
Control accuracy
+/-3% F.S. (at an operating differential pressure of 0.3
MPa and temperature of 25 oC)
Repeatability
+/-1% F.S.
Temperature
characteristics*1
+/-2% F.S. (15 to 35 oC; 25 oC basis)
+/-5% F.S. (0 to 50 oC; 25 oC basis)
Pressure characteristics*2
+/-2% F.S. (Standard operating differential pressure
basis)
Settling time*3
0.5 s or less
Control command method
Analog input
State when de-energized*4
Closed (Normally closed)
Analog input
Input mode
Flow rate command signal
Voltage
Input type
1 to 5 V
Input impedance
Approx. 1 MΩ
Current
Input type
4 to 20 mA
Input impedance
250 Ω or less
Analog
output
Output mode
Flow rate output signal
Voltage
Output type
1 to 5 V
Output
impedance
Approx. 1 kΩ
Current
Output type
4 to 20 mA
Load impedance
50 to 600 Ω
Switch input
Input type
1 point (photo coupler isolation)
Input mode
Valve fully open command
Internal resistance
5 kΩ
Switch output
Output type
1 point (NPN open collector, PNP open collector)
Output mode
Error output
Switch operation
Inverted output
Maximum load current
80 mA
Maximum applied voltage
(NPN only)
30 VDC
Internal voltage drop
(Residual voltage)
1.5 V or less (at 80 mA load current)
Delay time
5 ms or less
Protection
Switch output polarity protection
Over current protection
Flow rate
display
output
Output mode
For connection with the digital flow monitor PFG310
Output type
4 to 20 mA
Load impedance
50 to 600 Ω
Display
LED indicator
2 points (power supply, error)
*1: Indicates the amount of fluctuation in the control accuracy when the temperature changes within the operating
temperature range.
*2: Indicates the amount of fluctuation in the control accuracy when the pressure changes within the specified
pressure range.
*3: The time when an operational differential pressure of 0.3 MPa, temperature of 25 oC, power supply voltage of 24
VDC, command flow rate of a step signal from 3% to 100% is input, the flow rate is set within +/-3% F.S. of the
command flow rate. The settling time may be longer in other operating conditions.
*4: This product is not suitable for applications which require the flow to be shut off completely.
If it is necessary to completely shut off the flow rate, install a stop valve, etc. separately.

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6-3. Functional characteristics
(1) Analog input (flow rate command signal)
Note: A signal smaller than the minimum value of the
set controlled flow rate turns off the current to the
linear motor, which closes the valve.
(2) Analog output (flow rate output signal)
(3) Controllable range
Caution
Be sure to use the product within the controllable range.
Outside of the controllable range, the accuracy in the control specification may not
be satisfied, the flow rate may be low, flow rate control may be unstable, vibration
may be caused, the product temperature may be high and so on.
Input type
Flow rate command signal range
0 L/min: A
Set controlled
flow rate
Minimum
value: B
Set controlled
flow rate
Maximum
value: C
Voltage input
1 V
1.04 V
5 V
Current input
4 mA
4.16 mA
20 mA
Output type
A
B
Voltage output
1 V
5 V
Current output
4 mA
20 mA
0
A
C
Commanded flow rate
(L/min)
300
Analog input
(Flow rate command signal)
B
3
0
0
0.1
0.2
0.3
0.4
0.5
0.6
Operational differential pressure (MPa)
100
200
300
400
Flow rate(L/min)
009
0.05
Controllable
range
50
0
0
A
B
Flow rate (L/min)
300
Analog output
(Flow rate output signal)
0

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(4) IN side straight pipe length and accuracy (reference value)
- The smaller the piping size, the more the built-in flow sensor is susceptible to the length of straight
pipe.
- The lower the flow rate, the less the product is susceptible to the length of straight pipe.
- To maintain the specified +/-3% F.S. accuracy, set the length of straight pipe to at least 80 mm.
+/-5
+/-6
+/-4
+/-3
+/-2
+/-1
0
20
40
60
80
100
Piping length (mm)
accuracy(% F.S.)
+/-0
Piping length
IN side
OUT side

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7. Dimensions
PFCQ531-04
, Thread depth 5

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PFCQ531-04
with bracket
PFCQP-910S-31
Protective plug

- 15 -
8. Component Drawing of Parts in Contact with Fluid and Parts Names
Components
No.
Name
Material
Remarks
No.
Name
Material
Remarks
1
Attachment
Stainless steel
13
Tube
Stainless steel
2
O-ring
FKM
14
Motor body
Resin
3
O-ring
FKM
15
Nut
Stainless steel
4
Spacer
Resin
16
Wear ring
Stainless steel
DLC
5
Mesh
Stainless steel
17
Magnet
Rare earth
magnet
Ni plating
6
Sensor body
Resin
18
Ring
Carbon steel
Ni plating
7
Gasket
FKM
19
Shaft
Stainless steel
8
Rectification
mesh
Stainless steel
20
O-ring
FKM
9
Sensor chip
Silicon
21
Valve
Stainless steel
10
Circuit board
GE4F
22
Retainer
Resin
11
Gasket
FKM
23
Poppet
FKM
12
Body
Resin
24
Valve body
Resin

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9. Working Principle
This product has a built-in linear motor which changes the valve opening by moving the valve
element mounted to the linear motor, and thereby adjusting the flow rate inside the valve.
When the flow rate command signal is input to the product, the internal operation circuit performs
a comparison calculation with the flow rate measured by the flow sensor. The product drives the
linear motor based on that value to control the flow rate.
When the linear motor is de-energized, the valve is closed by the attractive force of the permanent
magnet mounted to the linear motor (Normally closed).
Flow rate command signal
Flow rate output signal
Flow sensor
Linear motor
Valve element
IN
OUT
Valve
Operation circuit

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10. Installation
10-1. Installation
Mounting the bracket
- Mount the bracket using hexagon socket head cap screws (4 pcs.).
- Apply a tightening torque of 1.4 to 1.6 N.m.
- To mount the product with a bracket, use M4 screws or equivalent (4 pcs.).
- The screws should be prepared by the user.
- Refer to “7. Dimensions” for the bracket thickness and the mounting hole locations.
Mounting screws (accessories)
M4 screws or equivalent
(To be prepared by the user)

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M4 screws or equivalent
(To be prepared by the user)
Direct mounting
- Use M4 screws or equivalent (4 pcs.) for mounting.
- The screws should be prepared by the user.
- See “7. Dimensions” for the threaded hole locations and depth.
Mounting location
- Give consideration to the size of the control panel and the installation method so that the
surrounding of the product will be 45 oC or below (or 35 oC or below when using the product
within the guaranteed accuracy range).
- When mounting the products side by side, be sure to take measures against overheating by
providing a 20 mm or more space between them.
20 mm or more

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10-2. Air supply
- Use fluid that is compliant with JIS B 8392-1 1.1.2 to 1.6.2, ISO8573-1 1.1.2 to 1.6.2.
Using the following pneumatic circuit satisfies the air quality class described above.
Example of a recommended pneumatic circuit
(for compressed air)
Dryer
IDF
IDU
Micro mist
separator
AMD
AFD
Regulator
AR
IR
Air filter
AF
Flow controller for Air
PFCQ