Flowkinetics Fks 1dp-pbm User manual

FKS 1DP-PBM Multi-Function Meter

Pressure, Speed & Flow

User’s Manual

Contact Information

Email:

inform@flowkinetics.com

Web:

www.flowkinetics.com

Mail:

FlowKinetics LLC

4700 Shoal Creek Dr.

College Station, TX 77845

USA

Telephone:

(979) 680-0659

(888) 670-1927

Fax:

(979) 680-0659

IMPORTANT

Read all instructions and

precautions in this manual

before use. Keep this manual

for future reference.

April 19 - 2018

Table of Contents

Page

Limitations Of Usage And Cautions......................................................... 5

Warranty................................................................................................... 5

Unpacking / Parts List .............................................................................. 6

Overview / Features................................................................................. 7

Description of Controls & Display ............................................................ 8

General Operation:................................................................................... 9

Q: How Do I Insert Batteries / Use Wall Power? ...............................................9

Q: How Do I Connect the Tubing? .....................................................................9

Q: How Do I Switch the Unit On (and Off)? .......................................................9

Q: How Do I Adjust the Screen Contrast? .......................................................10

Q: How Do I Know if the Batteries Need Replacement?.................................10

Q: How Do I Change the Auto-Zero Interval?..................................................10

Q: How Do I Know If the Meter is Overloaded? ..............................................11

Q: How Do I Change the Smoothing of My Data?...........................................11

Measuring Pressure...............................................................................13

Q: How Do I Change Units?.............................................................................13

Q: How Do I Measure the Minimum (L) and Maximum (H) Reading ..............13

Q: How Do I Reset Min/Max?...........................................................................13

Q: How Do I Hold or Freeze the Display? .......................................................13

Q: How Can I Estimate if the Pressure May Be Too Unsteady for Accurate

Measurement?..................................................................................................13

Q: How Do I Estimate the Uncertainty in My Pressure Measurements? ........13

Q: How Do I Store a Pressure Measurement in Memory?..............................14

Q: How Do I Recall My Pressure Measurements From Memory? ..................14

Measuring Speed...................................................................................16

Q: How Do I Change Units?.............................................................................16

Q: How Do I Measure the Minimum (L) and Maximum (H) Reading ..............16

Q: How Do I Reset Min/Max?...........................................................................16

Q: How Do I Hold or Freeze the Display? .......................................................16

Q: How Can I Estimate if the Air Speed May Be Too Unsteady for Accurate

Measurement?..................................................................................................16

Q: What Probes can I use with the FKS 1DP-PBM?.......................................16

Q: How Do I Connect the Pitot Probe? ............................................................16

Q: How Do I Change K?...................................................................................17

Q: How Do I Measure Standard Speed? .........................................................17

Q: How Do I Measure Actual Speed?..............................................................18

Q: How Do I Check the Stored Values for K, Patm and T? ............................19

Q: How Do I Set K, Patm and T to Default (Standard Conditions)? ...............19

Q: How Do I Estimate the Uncertainty in My Speed Measurements? ............19

Q: How Do I Store a Speed Measurement in Memory?..................................20

Q: How Do I Recall My Speed Measurements From Memory? ......................20

Measuring Flow Rate .............................................................................22

Q: How Do I Use the Pitot or S Probe Survey Routine? .................................22

Q: Can I Estimate the Uncertainty of My Flow Rate Measurement? ..............23

Q: How Do I Use Manual Logging to Perform a Survey?................................24

The Menu System..................................................................................25

Data Logging and Memory Management ..............................................26

Q: How Do I Manually Log a Reading (Store in Memory)? .............................26

Q: How Do I Configure the Meter for Automatic (Continuous) Logging?........26

Q: How Do I Start Automatic Logging?............................................................27

Q: How Do I Recall My Measurements From Memory?..................................28

Q: How Do I Download Memory to a PC? .......................................................29

Q: How Do I Clear the Memory?......................................................................30

Maintenance...........................................................................................31

Operational Maintenance .................................................................................31

Battery Maintenance ........................................................................................31

Specifications.........................................................................................32

Appendix A Understanding Uncertainty................................................. 35

Appendix B Performing a Pitot Probe Duct Traverse ............................ 37

Limitations Of Usage And Cautions

The FKS series of instruments are not intrinsically safe, and must not be used in dangerous or

hazardous areas. Servicing of these instruments incorporating battery changing must only occur

in a safe area. Use of the FKS series may require working in a hazardous environment.

Necessary safety precautions must be followed.

FlowKineticsTM LLC’s products (including the FKS series) are not authorized for use as any

component in a life support system or device or as component of an aircraft’s on board flight

system. Life support systems or devices are defined as any system that can sustain, monitor or

support life.

The pressure transducers used by the FKS system are compatible with most non-corrosive

gases, however toxic gases are not suitable, nor are liquid pressure measurements.

Any attempts to service or modify or alter the product in any way, will void the warranty and will

negate any right of claim against FlowKineticsTM LLC, relating to any liability in respect of the

product.

Warranty

All of FlowKineticsTM LLC's instruments have been assembled using strictly defined and

controlled procedures and tests, and are warranted against any faults in workmanship and

materials for one year from the date of purchase. Liability under this warranty is limited to repair

or replacement F.O.B. factory of any parts which prove to be defective within that time or

repayment of the purchase price at the Seller's option provided the product has been returned,

transportation prepaid, within one year from date of purchase. In no case is the Seller liable

beyond replacement of product F.O.B. factory or the full purchase price. This warranty does not

apply if the product or equipment is abused, altered, used at ratings above the maximum

specified, used with disregard of instructions and specified operating procedures, or otherwise

misused in any way. All technical advice, recommendations and services are based on technical

data and information which the Seller believes to be reliable and are intended for use by persons

having skill and knowledge of the application, on their own judgment. There are no implied

warranties of merchantability or of fitness for a particular purpose for goods covered hereunder.

In no event will the manufacturer be responsible for consequential, incidental or special

damages resulting from the use of this product.

Buyer's Remedies: The buyer’s exclusive and sole remedy on account of or in respect to the

furnishing of non-conforming or defective material shall be to secure replacement thereof as said

above. The seller shall not in any event be liable for the cost of any labor expended on any such

material or for any special, direct, indirect, consequential or incidental damages to anyone or

any property by reason of the fact that it shall have been non-conforming or defective.

Repairs: Authorization must be obtained before shipping items to FlowKinetics™ LLC for

repairs. When requesting a repair please include a detailed description of the problem with the

item, date of purchase, your P.O. or reference number and our invoice number if available.

Unpacking / Parts List

Carefully unpack your FKS 1DP-PBM meter. Ensure that there is no damage to

the instrument. If any components are damaged, make a record and contact the

shipper. The instrument is supplied with (some accessories are optional):

Item

Description

Quantity

FKS 1DP-PBM

Multi-function meter

Tubing

Flexible tubing for pressure

connection

FKS Manual

User reference

Cable6

6 ft Serial cable

SwiftLink

Software for downloading

memory to PC

Download from

www.flowkinetics.com

WPA

Wall power adapter

Optional

SwiftScan CD

and manual

Real time software for

monitoring the FKS outputs

and downloading them to a

Optional

Overview / Features

The FKS 1DP-PBM is a multi-function meter designed for accurate pressure,

speed and flow measurement. The meter is exceptionally easy to use due to its

prompt driven user interface and intuitive functioning.

Features of the PBM include:

Highly configurable operation

Differential, static and gauge pressure

Auto-Zero (automatic) function to remove any drift (internal valve)

Overload protection

Metric and Imperial units

Minimum & maximum reading

Data hold (screen freeze)

Turbulence indicator

K factor

Speed (both standard and actual)

Density correction

Intelligent automatic damping (with user selectable averaging or

smoothing)

Memory / data logging (up to 10,000 Rdgs) with recall statistics

Manual and automatic data logging

Flow rate (using inbuilt Pitot traverse routine or memory log)

Powerful statistics to estimate measurement uncertainty

PC compatibility (download software included)

Variable screen contrast

Wall or battery power

Description of Controls & Display

Controls of the FKS 1DP-PBM are shown below:

Example Display Presentations for Pressure and Speed are Shown Below:

P=1.67inH2O T

H2.01 L-0.21

V=6702ft/min

H8291 L6231

Measured pressure

Maximum recorded

value (H)

Calculated speed

Maximum recorded

value (H)

Turbulence indicator

(appears if Pressure

fluctuations > 10%)

Minimum recorded

value (L)

Minimum recorded

value (L)

Positive (+) pressure

connection barb

On/Off button

Range control or

selector

External power jack

plug

Negative (-) or Reference

pressure connection barb

Hold/Manual log button

Screen contrast control

PC serial port connector

General Operation:

Q: How Do I Insert Batteries / Use Wall Power?

Batteries: The unit uses two 9V batteries. The batteries are inserted by removing

the cover located on the back of the instrument. The cover slides off. The ribbon

under the batteries can be used to ease battery removal. Only use new batteries

(dry Alkaline leak proof) and discard the old batteries in compliance with

regulations.

Wall Power: An AC adaptor power supply can be supplied with the instrument as

an option. The adaptor can operate from 100VAC to 240VAC 50-60Hz supplies and

provides 1100mA at 9VDC. The adaptor has the facility for easy interchange

between US, European, English and Australian plugs. To use, simply insert the

jack from the adapter into the jack plug on the face of the instrument (see

Description of controls). It is not necessary to remove the batteries, as they are

automatically disconnected. Do not attempt to use the supplied adapter as a

battery charger.

CAUTION: Use of any power adaptor other than that supplied (optional) with

the instrument will remove any rights of claim against FlowKineticsTM LLC,

relating to product liability or consequential damage against a third party

and will void the warranty. If an alternative adaptor is used, its output

voltage range must be regulated and within:

DCADAPTORDC VVV 129

If the meter is stored, or not used for over a week, the batteries must be removed.

Q: How Do I Connect the Tubing?

Pressure: The supplied flexible tubes attach over the barbs labeled P+ and P-. A

higher pressure at port P+ than port P- will result in an indicated positive pressure.

To measure static or gauge pressure, tubing can be connected to the P+ barb. An

indicated positive pressure shows that the static or gauge pressure is higher than

atmospheric (or the pressure at P-).

Speed: To measure speeds, the P+ port should be connected to the Total

pressure port on the Pitot and the P- port connected to the Static port (see How

Do I Connect the Pitot Probe?) of the Pitot probe.

CAUTION: The FKS series are not suitable for use with toxic or corrosive

gases or for liquid pressure measurement. The series are not approved for

use in any life support application.

Q: How Do I Switch the Unit On (and Off)?

To switch the meter on, press in the On/Off button. You will hear and feel a click

indicating unit power up. To switch the unit off, press the On/Off button again. If

the Range selector is set to a pressure unit, the instrument will show the meter

model description and then indicate that that the instrument is performing a

scheduled Auto-Zero. If the Range selector is set to a speed unit, the meter will

additionally show the stored speed and flow settings (K, Patm and T) in both

metric (kPa and C) and imperial units (inHg and F). Cycling the meter On/Off

can be used to rapidly check the speed/flow settings. The memory remaining (in

number of readings) for both manual (Mem(M):xxxxRdgs) and automatic

logging (Mem(A):xxxxRdgs) will be briefly displayed (for 2.5 seconds).

The maximum number of readings for manual and automatic logging is 4,000 and

6,000 respectively.

Q: How Do I Adjust the Screen Contrast?

Screen contrast is adjusted by rotating the screen contrast knob. Only use your

fingers to operate this control.

Q: How Do I Know if the Batteries Need Replacement?

If the battery voltage is too low, the message Low Battery will be

displayed at startup. Also a Bwill appear at the top RHS of the display wile the

meter is operating. If the battery is too drained for the meter to work properly, the

message Battery Depleted will be displayed at startup and the meter

will not continue until the batteries are replaced or a wall power supply is used.

Q: How Do I Change the Auto-Zero Interval?

The PBM meter contains a miniature solenoid valve that is used to automatically

remove any offset or drift from the differential pressure transducer (without having

to disconnect the meter from the pressure source). You can set the interval

between zeroing from 0.2 minutes (12 seconds) to 99.9 minutes (1 hour 40

minutes). The default interval is 6 minutes 06.0. To change the interval set the

Range selector to Menu. The menu will cycle through various functions. When

Set Auto-Zero appears, rotate (any direction) the Range control to

select it. The menu will prompt, Set Zero Rotate followed by

Interval minutes. Rotate the Range selector (any direction or unit).

The screen will display 00.0. The first digit will begin to blink. To increment this

digit press the Hold/Log button. You can also keep the button pressed to advance

rapidly. If the displayed digit increments beyond 9, it will wrap around and continue

from 0. When the desired value for this digit is set, rotate the Range selector (any

direction or unit). The second digit will begin to blink. Use the Hold/Log button to

set the desired value; similarly for the third digit.

The instrument will then return to measurement mode. As an example, to set an

interval of 3½ minutes, the display would be set to 03.5. To convert seconds to

its decimal equivalent, divide the number of seconds by 60 and round off if

necessary. If an interval of 00.0 or 00.1 is set, the unit will default to an

interval of 15 seconds. The interval you set is NOT stored in memory and will not

be retained after switching the unit off (to maximize battery life). Upon power up,

the meter will use its default interval (6 minutes). Note: the Auto-Zero can

significantly affect battery life. Using a small interval (e.g. 2 minutes or less) will

reduce life, but may be needed for your application.

Q: How Do I Know If the Meter is Overloaded?

If the pressure rating for the transducer is exceeded, the meter will indicate on the

display an overload condition (Overload). The internal solenoid valve will

actuate to equalize pressure across the transducer to reduce the possibility of

damage. Pressure should be relieved immediately to avoid damage.

CAUTION: The maximum differential pressure that may be imposed on the

transducer is 5psi, with a maximum line pressure of 10psi.

Q: How Do I Change the Smoothing of My Data?

The FKS 1DP-PBM meter contains sophisticated routines to process your

measurements (very useful when they are unsteady or fluctuating). Two methods

can be used to smooth your readings. An exponential moving average (sometimes

called exponential smoothing) can be used (somewhat similar to a normal moving

average) and of the form:

2)1(12*PffPP 

(Exp. Smoothing)

where P2* is the new pressure estimate (shown on the display), P2 is the latest

pressure value measured from the transducer and P1 is the last pressure

estimate. In the PBM meter, fis adjusted continuously (adaptive) depending on the

level of fluctuation of the measured pressure. If there is little fluctuation f will be

close to zero. If fluctuation is large, fhas a maximum value of 0.9. Thus fis

continuously adjusted by the meter (between 0 and 0.9) to provide the most stable

reading.

The second method that can be used is a simple averaging of readings

(Average). The meter will read the output from the pressure transducer

multiple times, and then average these values. The meter will continuously adjust

the number of averages (from 5 to 75 averages). This operation may be

noticeable, as the screen update rate may change as the meter changes (adapts)

the number of averages to give the best and most stable estimate of the pressure

or speed.

To select the method you want set the Range selector to Menu. The menu will

cycle through various functions. When Smooth/Average appears, rotate

(any direction) the Range control to select it. The menu will cycle, Exp.

Smoothing followed by Averaging. Rotate the Range selector (any

direction or unit) when the desired method is displayed. The instrument will then

return to measurement mode. The method you selected is stored in memory and

will be retained after switching the unit off. For very unstable readings, the

exponential smoothing may offer a more stable estimate, where the averaging will

offer a quicker estimate.

Measuring Pressure

Q: How Do I Change Units?

Units are changed by rotating the Range selector knob. The knob has no stop and

can rotate more than 360 degrees.

Q: How Do I Measure the Minimum (L) and Maximum (H) Reading

The Minimum and Maximum readings are continuously shown by the FKS meter

on the second line of the display. The maximum reading is preceded by H and the

minimum reading is preceded by L. No units are shown but correspond to the units

displayed on the first line.

Q: How Do I Reset Min/Max?

To reset the Min/Max (or L-H) readings, simply change the units (to any other unit

setting) by rotating the Range knob and then set back to your desired units.

Q: How Do I Hold or Freeze the Display?

Press the Hold/Log button for less than 2seconds. The display will freeze,

indicated by the appearance of a Hat the top RHS of the display. To resume

operation, press the Hold/Log button again.

Q: How Can I Estimate if the Pressure May Be Too Unsteady for Accurate

Measurement?

If the measured pressures fluctuate more than 10%, an indicator Twill appear at

the top RHS of the display. This may suggest that another measurement location

may be necessary.

Q: How Do I Estimate the Uncertainty in My Pressure Measurements?

The FKS meter contains powerful statistical routines to estimate the uncertainty in

your measurements. To implement this function, rotate the Range selector to

Menu. (For a full description of the uncertainty calculation, see Appendix A). The

menu will cycle through various functions. When Calc Uncertainty

appears, rotate (any direction) the Range control to select it. The menu will cycle

95.5% Prob. followed by 99.7% Prob. Select the probability you

want to use by rotating the Range control when the interval is on the display. The

instrument will then return to measurement mode. Indicated pressures will have

the form:

(mean pressure)

P=1.21+-0.008

(standard deviation of the mean pressure)

If you had selected (as an example) 95.5% prob., then the presented information

can be interpreted as:

The true mean pressure value is expected to lie within 1.21+0.008 and 1.21-0.008

to a 95.5% probability. So we can expect the actual pressure to be within 1.202 to

1.218 with a 95.5% probability. As the meter continuously reads the applied

pressure, new estimates of the mean and standard deviation will be displayed.

When in Uncertainty mode, H and L values will not be displayed as units are

presented on line 2. Uncertainty mode can be switched off in two ways:

1. Use the menu system and reselect Calc Uncertainty.

This mode will then toggle off, with the screen displaying

Uncertainty Off before the unit resumes operation.

2. Cycle the FKS 1DP-PBM Off and On.

Q: How Do I Store a Pressure Measurement in Memory?

To store a single value to memory (manual logging), press the Hold/Log button for

greater than 2seconds. The display will show Point Logged followed by

ID: x where xis the group identification number of your readings. The ID is a

simple way of grouping measurements. You can have up to 255 individual IDs

starting from 1. When recalling memory, an average, H and L of the readings in an

ID will be calculated and shown on the screen. While recording measurements in a

specific ID, you should not change the instrument’s units. To increment the ID

(they increment sequentially), press the Hold/Log button for greater than

4seconds. The display will then change from Point Logged followed by

ID: x to New ID&Data Log followed by ID: y. Where y is the

new ID (equal to the last ID+1). To clarify the use of IDs, say you have taken

pressure measurements in a duct section. These measurements have been stored

to ID=1. You move to another location where you want to measure air speed.

These speed readings are not associated with the previous pressure readings. So

to store them, you increment to the next group ID (say 2). See Data Logging and

Memory Management for details of memory management.

Q: How Do I Recall My Pressure Measurements From Memory?

For full details on the functioning of memory, see Data Logging and Memory

Management. The FKS 1DP-PBM meter recalls the data stored in a group ID; it

calculates the average of that group, as well as the minimum (L) value and

maximum (H) value in the group. Individual readings are not displayed. The meter

will sequentially process all stored IDs, starting from 1, showing the average,

minimum and maximum for each. To view individual readings, download the

memory to a PC (see Data Logging and Memory Management). To view your

manually logged data:

Set the Range selector to Menu. The menu will cycle through various functions.

When Logging Options appears, rotate (any direction) the Range

control to select it. The menu will cycle through various options. When, Review

Data is displayed, rotate the Range selector (any direction or unit). The unit

display will show Manual Log Data. The meter will indicate that the

data in the first group ID is being processed. The meter will display for 2 seconds

the group ID number and the number of readings in the group (Ntot) followed

by the average value (of pressure), as well as the H and L value in the group. An

example of storage and recall is shown in Table 1 (with pressure and speed

storage in separate group IDs) and the sketch below.

Continue to rotate the Range selector to index through the group IDs. After

completing the recall of the manual log data, the unit will recall the automatic log

data, if any. See Data Logging and Memory Management for details. The

instrument will then return to measurement mode.

Table 1 Group ID Use and Memory Recall

Group ID

Stored Values

Average

0.201

psi

0.315

psi

0.442

psi

0.058

psi

0.254

psi

0.442

psi

0.058

psi

1090

ft/min

1110

ft/min

1081

ft/min

1100

ft/min

1121

ft/min

1060

ft/min

1094

ft/min

1121

ft/min

1060

ft/min

Values (with units) stored in Memory

MR: Shown during memory recall (shown shaded)

I2 P=0.254psi

H0.442 L0.058

Group ID number (2 shown)

Average pressure (or speed)

Measuring Speed

The PBM uses differential pressure probes (Pitot or S type) to take speed

measurements.

Q: How Do I Change Units?

Units are changed by rotating the Range selector knob. The knob has no stop and

can rotate more than 360 degrees.

Q: How Do I Measure the Minimum (L) and Maximum (H) Reading

The Minimum and Maximum readings are continuously shown by the FKS meter

on the second line of the display. The maximum reading is preceded by H and the

minimum reading is preceded by L. No units are shown but correspond to the units

displayed on the first line.

Q: How Do I Reset Min/Max?

To reset the Min/Max (or L-H) readings, simply change the units (to any other unit

setting) by rotating the Range knob and then set back to your desired units.

Q: How Do I Hold or Freeze the Display?

Press the Hold/Log button for less than 2seconds. The display will freeze,

indicated by the appearance of an Hat the top RHS of the display. To resume

operation, press the Hold/Log button again.

Q: How Can I Estimate if the Air Speed May Be Too Unsteady for Accurate

Measurement?

If the measured pressures fluctuate more than 10%, an indicator Twill appear at

the top RHS of the display. This may suggest that another measurement location

may be necessary.

Q: What Probes can I use with the FKS 1DP-PBM?

Any Pitot static probe or S type probe can be used. Most Pitot probes have unity

calibration coefficients (K factor). S type probes (used for dirty air streams) have

coefficients around 0.80 to 0.92. To set K, see below.

Q: How Do I Connect the Pitot Probe?

See the sketch below. P+ is the top left barb; P- is the top right barb. For

connection of other types of probes, the stagnation (total) pressure port should be

connected to the P+ barb; the static or reference pressure should be connected to

the P- barb.

Q: How Do I Change K?

To set K, or a probe’s calibration constant (default value = 1), set the Range

selector to Menu. The menu will cycle through various functions. When Set K

factor appears, rotate (any direction) the Range control to select it. The

menu will prompt, Set K Rotate followed by K factor. Rotate the

Range selector (any direction or unit). Press & Rotate will be briefly

displayed. The screen will display 0.00. The first digit will begin to blink. To

increment this digit press the Hold/Log button. You can also keep the button

pressed to advance rapidly. If the displayed digit increments beyond 9, it will wrap

around and continue from 0. When the desired value for this digit is set, rotate the

Range selector (any direction or unit). The second digit will begin to blink. Use the

Hold/Log button to set the desired value; similarly for the third digit. The instrument

will then return to measurement mode. Any calculated speeds will then use the K

factor you set. The K factor is stored in memory and will be retained after switching

the unit off. The measured speed multiplies K, see Appendix B. See the Pitot

probes instructions for the value of K (usually = 1 for most Pitot probes).

Q: How Do I Measure Standard Speed?

Standard speed corresponds to a density based on a pressure, Patm, of

101.325kPa (29.92 inHg @ 32ºF) and a temperature, T, of 21.1ºC (70ºF). The

FKS 1DP-PBM allows you to manually set Patm and T. These values can be set in

two ways:

1. Set the Range selector to Menu. The menu will cycle through

various functions. When Set Patm & Temp appears,

rotate (any direction) the Range control to select it. The menu will

prompt, Set Units Rotate followed by kPa

alternating with inHg @ 32F. When the desired unit appears,

rotate the Range selector (any direction or unit) to set in either

metric or imperial units. Depending on your selection, the screen will

display 000.00 (metric) or 00.00 (imperial). The first digit will

begin to blink. To increment this digit press the Hold/Log button. You

can also keep the button pressed to advance rapidly. If the

displayed digit increments beyond 9, it will wrap around and

continue from 0. When the desired value for this digit is set, rotate

the Range selector (any direction or unit). The second digit will begin

to blink. Use the Hold/Log button to set the desired value; similarly

for the third digit, etc. After setting the atmospheric or absolute

pressure, the unit will prompt for the Temperature to be set. After

setting, the instrument will then return to measurement mode. Any

calculated speeds will then use the values you set for Patm and T.

Patm and T are stored in memory and will be retained after

switching the unit off.

2. Set the Range selector to Menu. The menu will cycle through

various functions. When Reset K, Patm, T appears,

rotate (any direction) the Range control to select it. The menu will

indicate that K, Patm and T have been reset to default (i.e. standard

conditions). Note that K is also reset to 1 (default).

Q: How Do I Measure Actual Speed?

The atmospheric pressure (Patm, this is the absolute pressure in the flow to be

measured) and temperature (T) of your airflow measurements should be set

manually. To measure actual speed, the temperature and absolute (barometric)

pressure of the air to be measured must be known.

Set the Range selector to Menu. The menu will cycle through various functions.

When Set Patm & Temp appears, rotate (any direction) the Range

control to select it. The menu will prompt, Set Units Rotate followed

by kPa alternating with inHg @ 32F. When the display shows the units

you want, rotate the Range selector (any direction or unit) to set in either metric or

imperial units. Depending on your selection, the screen will display 000.00

(metric) or 00.00 (imperial). The first digit will begin to blink. To increment this

digit press the Hold/Log button. You can also keep the button pressed to advance

rapidly. If the displayed digit increments beyond 9, it will wrap around and continue

from 0. When the desired value for this digit is set, rotate the Range selector (any

direction or unit). The second digit will begin to blink. Use the Hold/Log button to

set the desired value; similarly for the third digit, etc.

After setting the atmospheric pressure, the unit will prompt for the Temperature to

be set. After setting, the instrument will then return to measurement mode. Any

calculated speeds will then use the values you set for Patm and T. Patm and T are

stored in memory and will be retained after switching the unit off

Q: How Do I Check the Stored Values for K, Patm and T?

The values of these parameters can be checked in two ways:

1. Before switching the unit on, set the Range selector to a speed unit.

On power up, the meter will show the stored speed and flow settings

(K, Patm and T) in both metric (kPa and C) and imperial units (inHg

and F). The unit can be cycled On/Off as needed.

2. Set the Range selector to Menu. The menu will cycle through

various functions. When View K, Patm & T appears,

rotate (any direction) the Range control to select it. The unit will then

display the stored K factor, followed by Patm and T in metric units

(kPa and C) followed by imperial units (inHg @ 32F and F). After

displaying each unit set for approx. 2 seconds, the instrument will

return to measurement mode.

Q: How Do I Set K, Patm and T to Default (Standard Conditions)?

Set the Range selector to Menu. The menu will cycle through various functions.

When Reset K, Patm, T appears, rotate (any direction) the Range

control to select it. The menu will indicate that K, Patm and T have been reset to

default (i.e. standard conditions). Note that K is also reset to 1 (default).

Q: How Do I Estimate the Uncertainty in My Speed Measurements?

The FKS meter contains powerful statistical routines to estimate the uncertainty in

your measurements. To implement this function, rotate the Range selector to

Menu. (For a full description of the uncertainty calculation, see Appendix A). The

menu will cycle through various functions. When Calc Uncertainty

appears, rotate (any direction) the Range control to select it. The menu will

prompt, 95.5% Prob. followed by 99.7% Prob.. Select the

probability you want to use by rotating the Range control when the interval is on

the display. The instrument will then return to measurement mode. Indicated

speeds will have the form:

(mean speed)

V=6790+-18.2

(standard deviation of the mean speed)

If you had selected (as an example) 99.7% prob., then the presented information

can be interpreted as:

The true mean speed value is expected to lie within 6790+18.2 and 6790-18.2 to a

99.7% probability. So we can expect the actual speed to be within 6771.8 to

6808.2 with a 99.7% probability. As the meter continuously reads the applied

speed pressure, new estimates of the mean and standard deviation will be

displayed.

When in Uncertainty mode, H and L values will not be displayed as units are

presented on line 2. Uncertainty mode can be switched off in two ways:

1. Use the menu system and reselect Calc Uncertainty.

This mode will then toggle off, with the screen displaying

Uncertainty Off before the unit resumes operation.

2. Cycle the FKS 1DP-PBM Off and On.

Q: How Do I Store a Speed Measurement in Memory?