Teledyne HASTINGS Everywhereyoulook 201 Series Скачать руководство пользователя страница 21 | Manualshive

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Teledyne HASTINGS Everywhereyoulook 201 Series Скачать руководство пользователя страница 21

141-072011 - 201/203 Series

Page 21 of 23

D) This formula provides approximate results that tend to be undersized because it neglects
pressure drops internal to the flow controller, compressible gas effects and temperature effects.
Multiply the result by

≈

1.5 to get the expected minimum orifice size that can reliably pass the

desired flows at the expected pressures.

Where:

Formula

1:

Formula

2:

D

= Orifice

Diameter

Q

= Flow rate in standard volumetric unit (slm, sccm, scfh)

P

0

= Standard Pressure (760 Torr, 101.325 kpa)

P

u

= Upstream pressure in absolute units (use minimum expected value)

P

d

= Downstream pressure in absolute units (use maximum expected value)

γ

= Ratio of specific heats,

≈

1.2 for monatomic gases, 1.4 otherwise

ρ

0

= Density of gas @ standard pressure and temperature of flow unit

π

= Pi

(3.1415…)

σ

= Specific gravity of gas (ratio of gas density to density of air)

Choose the available orifice with the closest diameter that is larger than the calculated diameter.
Orifice diameters (inches) available are 0.023, 0.032, 0.046, 0.086, 0.130, 0.156, 0.250, 0.312,
0.375, 0.500 (large base only). Contact factory to order new orifice.

As an example, if the maximum controlled flow will be 1000 slm of air with an upstream pressure of
50 psig and exhausting to atmospheric pressure the minimum orifice diameter calculated from the
previous equation would be 0.225 inches. The next larger orifice that has a diameter of 0.250 inches
should be installed.

4.7.1. HFC-203

Orifice

To change the orifice in the HFC-203 unit, the valve must be dismantled. Remove the four 1/4"
Allen head machine screws in the top of the main valve. Lift off the valve top, exposing the spring

and diaphragm.  Note that a small brazed ball bearing
is on the down stream side of the valve top.  Remove
the spring and diaphragm assembly.  The orifice is
located in the bottom of the valve body and can be
removed with a 9/16 socket wrench.  See Figure 4.5.

To reinstall an orifice, first install the gasket onto the
orifice (replacement gaskets can be obtained from the
factory). Next screw the orifice into the valve base.
Snug up the orifice but do not over tighten. Place
diaphragm assembly into the base. Line up the two
small holes in the diaphragm with the two small holes

in the valve base. Place the spring on top of the

(

)

4

2

0

0

2

8

π

ρ

σ

P

P

P

P

Q

D

d

u

d

−

=

4

2

0

0

2

2

16

π

ρ

γ

σ

P

P

Q

D

u

=

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Содержание HASTINGS Everywhereyoulook 201 Series

Страница 1: ...INSTRUCTION MANUAL 201 203 205 207 SERIES FLOW METERS CONTROLLERS TELEDYNE HASTINGS INSTRUMENTS I S O 9 0 0 1 C E R T I F I E D ...

Страница 2: ...evision D Document Number 141 082005 August 2005 Revision E Document Number 141 062008 June 2008 Revision F Document Number 141 092008 September 2008 Revision G Document Number 141 022009 February 2009 Revision H Document Number 141 102009 October 2009 Revision J Document Number 141 102009A October 2009 Revision K Document Number 141 082010 August 2010 Revision L Document Number 141 072011 July 20...

Страница 3: ...2 4 MECHANICAL CONNECTIONS 9 2 5 ELECTRICAL CONNECTIONS 9 2 6 OPERATION 10 2 7 RANGE CHANGING 14 2 8 VALVE OVERRIDE CONTROL 14 3 THEORY OF OPERATION 15 3 1 OVERALL FUNCTIONAL DESCRIPTION 15 3 2 SENSOR 15 3 3 ELECTRONICS 15 3 4 SHUNT 16 3 5 VALVE 17 4 MAINTENANCE 18 4 1 AUTHORIZED MAINTENANCE 18 4 2 TROUBLESHOOTING 18 4 3 ADJUSTMENTS 19 4 4 END CAP REMOVAL 20 4 5 PRINTED CIRCUIT BOARD REPLACEMENT 2...

Страница 4: ...rization circuitry is employed Should recalibration in the field be desired a calibration standard is required the customer needs to simply set the zero and span points There will be no appreciable linearity change of the instrument when the flowing gas is changed MODULAR SENSOR The Hastings 200 series flow instrument incorporates a removable replaceable sensor module Field repairs to units can be...

Страница 5: ...ifications HFC 203 207 Accuracy1 and Linearity 1 F S Repeatability 0 05 F S Std Pressure Rating 500 psig High Pressure Option Proof tested to 1500 psig Pressure Coefficient 0 0067 psi 0 1000 psig N2 typical Control Valve DP Per customer order Leak Integrity 1x10 9 sccs Temperature Coefficient Zero 0 035 FS C 0 60 C Span 0 05 FS C 0 60 C STP 0 C and 760 Torr Power 15 Volt flow meter 14 16 VDC 30 mA...

Страница 6: ...d to the power supply common external to the flow controller to complete the loop since the signal common is galvanically isolated internally from the supply common This line must be current limited 50 mA to prevent short circuit currents from damaging the receiving circuit in the flow controller 1 5 Other Accessories 1 5 1 Hastings Power Supplies Hastings power supply display units are available ...

Страница 7: ...5 2 Interconnecting Cables Cables are available from Hastings in various lengths to connect from the 15 pin D connector on the back of Hastings power supplies directly to any of the 200 series and 300 series flow instruments including digital versions More information about the available cables can be found in the THPS 400 bulletin on the Hastings web site http www teledyne hi com pdfs bulletins h...

Страница 8: ...ent power spikes reaching the instrument The Hastings power supplies described in Section 1 4 1 satisfy these power requirements The Hastings 200 series flow instruments 24 Volt versions require 14 32 VDC 1 9 Watts HFM 201 205 and 4 2 Watts HFC 20203 207 for proper operation The supply voltage should be reasonably regulated as power supply ripple may propagate to the output The supply common is ga...

Страница 9: ... holes for special mounting can be added to the end cap as desired The standard inlet and outlet fittings for the 201 203 are 0 5 and 0 75 Swagelok optional VCR VCO NPT and metric fittings are available The standard inlet and outlet fittings for the 205 207 are 1 Swagelok optional VCR VCO and metric fittings are available The O rings for the end cap and the sensor are Viton optional Kalrez Buna N ...

Страница 10: ...o the voltage reference and the other end to ground The center lead would then be connected to setpoint input If a valve override switch is not desired the unit is ready for use at this time If the override switch is desired connect the center pin of a single pole three position switch with the center off position to pin 8 of the DA 15 15 Volt Pin 6 of the DE 9 24 Volt Connect a voltage source 10 ...

Страница 11: ... introduced with increased pressure It is directly proportional to the change in specific heat versus pressure for that particular gas For helium there is virtually no change in indicated output for nitrogen the indicated output will increase at approximately 0 0067 psi which is the pressure coefficient Thus Actual flow indicated flow 1 pressure pressure coefficient 2 6 4 Blending of Gases In the ...

Страница 12: ... was set up the display could indicate in flow units or percent of full scale Hastings Power Supply Feature Guide Feature Model 40 Power Pod 100 Power Pod 400 Digital Readout 9 9 9 15 Volts 9 9 9 Analog Outputs 9 9 9 Controller 9 9 Analog Control 9 Front Panel Override 9 9 Totalizer 9 4 20 mA 9 9 Ratio Control 9 Alarms 9 9 9 Multi Channel Display 9 Conversion Factors 9 9 9 Communications RS232 RS2...

Страница 13: ...stall one jumper vertically between the outside two pins pins 1 3 This will tie Pin 1 of the DE 9 connector to the valve control circuit and allow the controller to maintain the external process variable equal to the desired setpoint The 5 Volt reference is not available in this configuration 2 6 8 Response to Command Changes The response of the control circuit to changes to the command signal is ...

Страница 14: ... Range Changing The range of the flow controller can be changed in the field if recalibration facilities are available The flow controller may require a different orifice which can be purchased separately from the factory A listing of the orifices available and their flow rates can be found in Section 5 0 The instructions to change the flow range can be found in Section 4 6 2 8 Valve Override Cont...

Страница 15: ...e 3 1 Thermocouples TC 1 and TC 2 are welded at equal distances from the midpoint and develop equal outputs at zero flow When flow occurs through the tubing heat is transferred from the tube to the gas on the inlet side and from the gas back to the tube on the outlet side creating an asymmetrical temperature distribution sees Figure 3 2 The thermocouples sense this decrease and increase in the cap...

Страница 16: ...rement of flow rates higher than the 10 sccm full scale is achieved by dividing the flow with a fixed ratio shunting arrangement as is illustrated in Figure 3 3 This is accomplished by placing the measuring capillary tube parallel with one or more dimensionally similar channels called a laminar flow element LFE Therefore the sensor only needs to heat the gas passing through the capillary tube resu...

Страница 17: ...ed pilot valve When pressure is first applied and the pilot valve is closed system pressure Pu is much higher than the bonnet pressure Pb Pu will push up the diaphragm against Pb and the main flow will initiate Flow through the restriction of the bleed screw Qb will also initiate Since Qb is flowing into the bonnet chamber and the pilot flow Qp is shut off this will pressurize the bonnet chamber a...

Страница 18: ...tage is less than 3 00 VDC then turn the orifice clockwise until flow stops SYMPTOM Output of unit is proportional to flow but extremely small and not correctable by span pot CAUSE Sensor is not being heated ACTION Unplug connector J2 Check the following resistance The resistance between pins 2 3 of the sensor should be approximately 2500 ohms see Figure 3 1 on page 8 The resistance between pins 1...

Страница 19: ...s Replace O rings if required or recalibrate as necessary 4 3 Adjustments 4 3 1 Calibration Procedure Figure 4 1 NOTE Adjusting the SPAN pot will require the use of a calibration reference in Step 5 1 Connect power cable to D connector as specified in Section 2 7 Allow instrument to warm up for 30 minutes with 10 flow and instrument in AUTO position 2 Set ZERO R13 on 15 Volt R20 for 24 Volt potent...

Страница 20: ... of the above procedure Recalibrate if any components were changed or if any potentiometers were adjusted 4 6 Sensor Replacement If the sensor fails or becomes plugged it can be removed Remove the cover and the PC board per Section 4 7 above Remove the three bolts holding the sensor to the instrument base Remove the sensor from the base noting the two O rings Parker 2 005 V884 75 between the senso...

Страница 21: ... only Contact factory to order new orifice As an example if the maximum controlled flow will be 1000 slm of air with an upstream pressure of 50 psig and exhausting to atmospheric pressure the minimum orifice diameter calculated from the previous equation would be 0 225 inches The next larger orifice that has a diameter of 0 250 inches should be installed 4 7 1 HFC 203 Orifice To change the orifice...

Страница 22: ... 23 diaphragm Examine the o ring on the valve top for damage if required Install the valve top ensuring that the ball bearing in the side is on the downstream side Tighten down the valve top evenly to insure a proper seal at the diaphragm ...

Страница 23: ...rkmanship during the warranty period Defective instruments should be returned to Hastings Instruments shipment prepaid together with a written statement of the problem and a Return Material Authorization RMA number Please consult the factory for your RMA number before returning any product for repair Collect freight will not be accepted 5 2 Non Warranty Repair Policy Any product returned for a non...

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