TSI Incorporated VelociCalc 8345, VelociCalc 8346, VelociCalc 8347, VelociCalc 8347A Operation And Service Manual

Ventilation Testing/Balancing

Model 8345/8346/8347/8347A

VELOCICALC®

Air Velocity Meters

Operation and Service Manual

1980277, Revision E

November 2002

Model 8345/8346/8347/8347A

VELOCICALC

Air Velocity Meters

®

Operation and Service Manual

1980277, Revision E

November 2002

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Address

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[phone]

LIMITATION OF WARRANTY AND LIABILITY. Seller warrants
the goods sold hereunder, under normal use and service as described in
the operator's manual, shall be free from defects in workmanship and
material for twenty-four (24) months, or the length of time specified in
the operator's manual, from the date of shipment to the customer. This
warranty period is inclusive of any statutory warranty. This limited
warranty is subject to the following exclusions:

a. Hot-wire or hot-film sensors used with research anemometers, and

certain other components when indicated in specifications, are
warranted for 90 days from the date of shipment.

b. Parts repaired or replaced as a result of repair services are

warranted to be free from defects in workmanship and material,
under normal use, for 90 days from the date of shipment.

c. Seller does not provide any warranty on finished goods

manufactured by others or on any fuses, batteries or other
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Buyer and all users are deemed to have accepted this LIMITATION OF
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exclusive limited warranty of Seller. This LIMITATION OF
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prompt attention to any problems. If any malfunction is discovered,
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CONTENTS

Chapters

1. Unpacking and Parts Identification ......1

Parts Identification ....................................2

2. Setting-Up................................................ 5

Supplying Power to the V

Installing the Batteries ............................5

Using the Optional AC Adapter ..............5

Auto Power Off Feature .......................... 6

Selecting the Display Units ....................... 6

Using The Telescoping Probe ..................7

Extending The Probe .............................. 7

Retracting The Probe.............................. 7

Articulating Probe (Model 8346/8347A).... 8

3. Operation ................................................. 9

Overview ...................................................9

Keypad Functions ..................................... 9

ON/OFF Key ............................................. 9

Measuring Velocity ................................. 10

Measuring Temperature .........................10

Flow Rate Function................................. 11

Entering Shape and Size...................... 11

Humidity Function (Model 8347/8347A) . 12

Entering Barometric Pressure ..............12

Time Constant Function.......................... 13

ELOCICALC......... 5

Using the Clear, Sample and Statistics

Functions ................................................14

Sample Function................................... 14

Statistics Function................................. 15

Clear Function ......................................16

Printer Port..............................................16

4. Maintenance .......................................... 19

Probe Tip ................................................19

Recalibration ........................................... 19

Cases...................................................... 20

Storage ...................................................20

5. Troubleshooting.................................... 21

Appendixes

A Specifications ........................................25

B DIP Switch Settings ............................... 29

C Standard Velocity vs. Actual Velocity..31

Chapter 1

Unpacking and Parts
Identification

Carefully unpack the instrument and accessories
from the shipping container. Check the individual
parts against the list of components in Table 1. If
any are missing or damaged, notify TSI or your
local distributor immediately.

Table 1. List of Components
Qty Item Description Part/model

1 Model 8345 VELOCICALC or

Model 8346 V
Model 8347 V
Model 8347A V

1 Carrying Case (8345/46) or

Carrying Case (8347/47A)
4 AA Alkaline batteries 1208013
1 AC Adapter (Optional)

115 V, NEMA-5

230 V, European CEE 7/16

230 V, Great Britain

240 V, Australian
1 Operation and Service Manual 1980277

ELOCICALC or
ELOCICALC or

ELOCICALC

8345
8346
8347
8347A
1319125
1319114

2613033
2613078
800169
2613105

1

Parts Identification

1

2

3

1. Keypad

2. Display

3. Printer Interface Port

4. Battery Access Cover

4

2

Chapter 1

Chapter 2

Setting-Up

Supplying Power to the VELOCICALC

The V

ELOCICALC can be powered in one of two

ways: four size AA batteries or the optional AC
adapter.

Installing the Batteries

Insert four AA batteries as indicated by the
diagram located on the inside of the battery
compartment. TSI ships the unit with alkaline
batteries. The V
operate with either alkaline or NiCd
rechargeable batteries. Carbon-zinc batteries
are not recommended because of the danger of
battery acid leakage. The typical battery life for
alkaline batteries at 20°C at 150 ft/min is
10 hours.

Using the Optional AC Adapter

The optional AC adapter allows you to power

ELOCICALC from a wall outlet. When

the V
using the AC adapter, the batteries (if installed)
will be bypassed. The AC adapter is not a
battery charger.

ELOCICALC is designed to

5

Auto Power Off Feature

ELOCICALC’s auto power off feature will

The V
automatically power the instrument off after a
specified time. In velocity mode, the instrument
will power off after 15 minutes provided that
the velocity is zero and no keys have been
pressed during this time. In temperature mode,
the instrument will power off after 15 minutes if
no keys have been pressed. This feature can be
turned off if desired by switching DIP switch #5
to the OFF position. See Appendix B, DIP
Switch Settings.

(Note: Any samples taken will not

ELOCICALC automatically powers off.)

V

be lost if the

Selecting the Display Units

The V

ELOCICALC is capable of displaying the

measured values in several different measurement
units, as shown in Table 2-2.

Table 2-2. Choices of Measurement Units

Velocity Temperature Flow Rate

ft/min °F ft3/min

m/s °C m3/hr

l/s

6 Chapter 2

If you wish to change the display units on your

ELOCICALC, see Appendix B, “DIP Switch

V
Settings.”

Using The Telescoping Probe

The telescoping probe of the V
the velocity, temperature, and humidity sensors.
When using the probe, make sure the sensor
window is fully exposed and the orientation dot is
facing upstream.

Extending The Probe

To extend the probe, hold the handle in one
hand while pulling on the probe tip with the
other hand.

Retracting The Probe

To retract the probe, hold the handle in one
hand while pushing on the probe tip with the
other hand. If you feel the probe antenna
binding, pull gently on the probe cable until
the smallest antenna section is retracted.
Collapse the rest of the antenna by pressing the
probe tip. Do not hold the cable while
retracting the probe as this prevents the probe
from moving.

ELOCICALC contains

Setting-Up 7

Articulating Probe (Model 8346/8347A)

The articulating probe has the ability to bend at a
90° angle for those hard to reach places. To bend
the probe of the Model 8347A, loosen the knurled
nut on the joint, bend the probe, and tighten the nut.
To straighten the probe, loosen the nut, straighten
the probe, and tighten the nut.

8 Chapter 2

Chapter 3

Operation

Overview

The Model 8345/46 VELOCICALC measures air
velocity and temperature and calculates volumetric
flow rate. The Model 8347/47A measures air
velocity, temperature, volumetric flow rate,
humidity, dew point temperature, and wet bulb
temperature. Models 8346 and 8347A have an
articulating probe. The V
statistics for groups of readings.

Keypad Functions

When pressing the keys on the front panel, the

ELOCICALC will beep to confirm the function. If

V
you press a key and the V
beep, then the V
function during the selected mode. The beep
function can be disabled by changing the internal
DIP switch (refer to Appendix B).

ON/OFF Key

Press the ON/OFF key to turn the V
and off. When the instrument is first turned on it
goes through a preprogrammed power-up sequence

ELOCICALC can compute

ELOCICALC does not

ELOCICALC does not allow that

ELOCICALC on

9

that includes an internal self-check. First, all
displayable items will appear for a few seconds. If
a problem is detected, the display will light ‘CAL’
to indicate that it should be returned for servicing
and calibration.

Measuring Velocity

Press the VELOCITY key to display velocity
measurements (the V
start in velocity mode). The velocity will be
displayed in ft/min or m/s depending on the DIP
switch settings (refer to Appendix B). Place the
end of the probe in the location where you want to
make the measurement. Make sure the sensor
window is fully opened and the red orientation dot
is facing upstream.

Measuring Temperature

Press the TEMP key to display air temperature
readings. The V
temperature readings in either degrees Celsius (°C)
or degrees Fahrenheit (°F), depending on the DIP
switch settings (refer to Appendix B). Allow about
30 seconds for the temperature reading to stabilize
after switching to temperature mode. This is
necessary because the velocity sensor is heated
during velocity mode, and some heat is conducted
down to the temperature sensor.

ELOCICALC will automatically

ELOCICALC will display

10 Chapter 3

Flow Rate Function

The V

ELOCICALC’s flow rate function can calculate

flow rate using a known area. The V
displays the volumetric flow rate in ft3/min, m3/hr,
or l/s, depending on the DIP switch setting (refer to
Appendix B). The flow rate can be calculated for a
round, square or rectangular duct. The shape and
size of the duct or other area through which the
flow will be measured must be entered.

Entering Shape and Size

Press the FLOWRATE key to put the

ELOCICALC in flow rate mode. The

V

ELOCICALC will prompt the user to enter the

V
shape and size, if this has not been done since
the instrument was turned on. The

ELOCICALC will request entry of the shape by

V
alternately displaying the rectangle and the
circle. If shape and size have

ELOCICALC will go directly to displaying

V
flow rate.

Press the up and down arrow keys (ÏÐ) to
select the shape of the area, rectangular
(square) or circular, to measure. Each time an
up or down arrow key (ÏÐ) is pressed, the
display will toggle between the circle and
rectangle. When the desired shape appears on
the display press either the ENTER or

Operation 11

ELOCICALC

been entered, the

FLOWRATE key. This will enter the shape
and the V

Use the up and down arrow keys (ÏÐ) to
select the size of the flow rate area. For a
circular flow shape the V
for one size, the diameter
Select the size and press either the ENTER or
FLOWRATE key to accept it. For a
rectangular area the V
two dimensions. First select the X dimension
and press either the ENTER or FLOWRATE
key, then select the Y dimension and press
either the ENTER or FLOWRATE key.
To change the shape or dimensions after they
have been entered, press the up and down
arrow keys (ÏÐ). Proceed as above to enter
the shape and dimensions.

Humidity Function (Model 8347/8347A)

Press the HUMIDITY key to toggle between
displaying % relative humidity, dew point
temperature, and wet bulb temperature. NOTE: To
display accurate wet bulb temperature, the correct
barometric pressure must be entered.

ELOCICALC will then ask for the size.

ELOCICALC will ask

of the circular area.

ELOCICALC will ask for

Entering Barometric Pressure

While wet bulb temperature is displayed, press
the up or down arrow key to display

12 Chapter 3

barometric pressure. Use the arrow keys to
change the barometric pressure and press
ENTER to accept it and return to measuring
mode.

NOTE: For temperature and humidity
measurements, make sure that at least 3 inches (7.5
cm) of the probe is in the flow to allow the
temperature and humidity sensors to be in the air
stream.

Time Constant Function

Momentarily press and release the TIME
CONSTANT key to view the current time constant.

To change the time constant, press and hold the
key. The available time constant choices (1, 5, 10,
15 and 20 seconds) will sequence on the display.
When the desired value is displayed immediately
release the key.

ELOCICALC will always store the chosen time

The V
constant when the meter is turned off. When the

ELOCICALC is turned on again, the last time

V
constant is used.

The time constant is actually an averaging period.

ELOCICALC display is always updated every

The V
second, however, the reading displayed is the
average reading over the last time constant period.

Operation 13

For example, if the current time constant is set to
10 seconds, the display will show readings
averaged over the previous 10 seconds, updated
every second. This is also called a 10 second
“moving average.”

Using the Clear, Sample and Statistics Functions

ELOCICALC has the ability to compute the

The V
average of a number of individual sampled
readings. When the SAMPLE key is pressed, the
currently displayed reading is added to a sample
buffer. When the STATISTICS key is pressed, the
sum of the readings in the sample buffer is divided
by the number of sampled readings to get the
average. The CLEAR key is used to clear out the
sample buffer in order to start taking a new
average.

Sample Function

Press the SAMPLE key to start the sample. The
display will flash “SAMPLE” for one time
constant and a number indicating the number of
sampled readings that are in memory. Then the
sampled value will be displayed.

The individual sampled values cannot be
recalled. Only the statistics of the sampled
values can be recalled. There are five different

14 Chapter 3

statistics buffers: one for both velocity and flow
rate, temperature, humidity, dew point
temperature, and wet bulb temperature. You
can switch between measuring modes and
sample data without affecting the statistics in
the buffer for another measuring mode. You
can later return to any mode and add additional
values to the existing statistics.

The statistics data will be lost when the
instrument is manually powered off. This data
can be kept upon power off by switching DIP
switch #6 to the ON position. See Appendix B,
DIP Switch Settings.

Statistics Function

Press the STATISTICS key to display the
average of the sampled values of the current
operating mode. The message “AVERAGE”
will appear along with a number (between 1 and

255) indicating how many sampled values were
averaged. The average value is then displayed
for one second. To keep displaying the average
value, press and hold the STATISTICS key. If
the STATISTICS key is pressed repeatedly, the
minimum, maximum, and count are displayed.
Additional values can be sampled after the
STATISTICS key has been pressed. The next
time the STATISTICS key is pressed, the

Operation 15

additional values are averaged with those
already accumulated.

Clear Function

Press the CLEAR key to erase the sampled
values in the buffer of the currently active
function. Pushing the CLEAR key for
velocity/flow rate will not affect the values in
temperature, humidity, dew point, or wet bulb
buffer. However, velocity and flow rate use the
same buffer, so clearing velocity will also clear
the flow rate.

Printer Port

If the optional Portable Printer is connected the
following will be printed: While pushing the
SAMPLE, STATISTICS or CLEAR key the
currently displayed data is transmitted to the printer
port. In flow rate mode, shape and size data is also
transmitted when it is entered or changed. The
value of the time constant is transmitted when it is
changed.

The data will print in a format such as 12345.67. If
you desire, the V
such as 12345,67 by switching DIP switch #4 ON.
See Appendix B, DIP Switch Settings.

ELOCICALC can print in a format

16 Chapter 3

Chapter 4

Maintenance

Probe Tip

Periodically inspect the probe tip to ensure that it is
clean. Dust and oil deposits on the velocity sensor
decrease the accuracy of the V

Caution: The V

To remove dust, blow it off with a gentle stream of
air or rinse it off with a gentle stream of water. To
remove a combination of dust and oil, rinse the
probe tip in isopropyl alcohol and then blow it off
with a gentle stream of air. Be careful not to allow

water to enter the articulating probe joint on the
Model 8346/8347A.

Recalibration

To maintain a high degree of accuracy in your
measurements, TSI recommends that you return
your instrument for annual recalibration. For a
nominal fee, we will recalibrate the unit and return

ELOCICALC must be switched

off for cleaning. Do not use high­pressure air or strong solvents to
clean the sensor tip; damage to the
sensors could result.

ELOCICALC.

19

it to you with a certificate of calibration and US
National Institute of Standards and Technology
(NIST) traceability. This 'annual checkup' assures
you of consistently accurate readings; it is
especially important in applications where strict
calibration records must be maintained.

Cases

If the instrument case or storage case needs
cleaning, wipe it off with a soft cloth and isopropyl
alcohol or a mild detergent. Never submerge the

ELOCICALC.

V

Storage

When storing the V
month, it is recommended to remove the batteries.
This prevents damage due to battery leakage.

ELOCICALC for more than a

20 Chapter 4

Chapter 5

Troubleshooting

Table 5 lists the symptoms, possible causes, and
recommended solutions for common problems
encountered with the V
symptom is not listed, or if none of the solutions
solves your problem, please contact TSI.

Table 5. Troubleshooting the VELOCICALC

Symptom

No display Unit not

Low or dead

Dirty battery

Battery
symbol is
blinking

ELOCICALC. If your

Possible
Causes

switched on

batteries

contacts
Batteries are
low

Corrective Action

Switch on the unit.

Replace the
batteries or plug in
the AC adapter.
Clean the battery
contacts.
Replace or
recharge batteries.

21

Symptom

Display
reads "LO"
Wrong AC

Low AC line

Dirty battery

Temperature
initially
reads high

Display
reads "ERR"

Possible
Causes

Low battery
charge

adapter

voltage

contacts
Temperature
sensor is still
warm from
velocity
mode
You are
trying to
enter more
than 255
readings

Corrective Action

Replace or
recharge batteries.
Replace with the
correct AC
adapter.
Correct the AC
line voltage or use
batteries.
Clean the battery
contacts.
Allow about 30
seconds before
reading
temperature.

Read or record the
average; clear the
sample register
and proceed.

22 Chapter 5

Symptom

Display
reads "CAL"

Velocity
reading
fluctuates
badly

Display says
"OVER"

Display
flashes
"888.8"

Possible
Causes

The

ELOCICALC

V
has detected
an internal
fault
The flow is
fluctuating

Velocity or
temperature
is too high
Velocity or
temperature
is too high

Corrective Action

Return to factory
for service.

Reposition the
probe in a less
turbulent section
of the flow or use
a longer time
constant.
Use an alternate
measurement
method.
Use an alternate
measurement
method.

WARNING!

Remove the probe from excess temperature
immediately: excessive heat can damage the
sensor.

Troubleshooting 23

Appendix A

Specifications

Specifications are subject to change without notice.
Specifications in parentheses () indicate metric equivalents.

VELOCITY:

Range: 0 to 6000 ft/min (0 to 30 m/s)
Accuracy

TEMPERATURE:

Range (8345/46): 0 to 200 °F (-17.8 to 93.3 °C)
Range (8347/47A): 14 to 140 °F (-10 to 60 °C)
Resolution: 0.1 °F (0.1 °C)
Accuracy

INSTRUMENT TEMPERATURE RANGE:

Operating (electronics): 40 to 113 °F (5 to 45 °C)
note: deleted probe line here
Storage: -22 to 194 °F (-30 to 90 °C)

VOLUMETRIC FLOWRATE:

Range

1&2

: 3.0% of reading or ± 3 ft/min

(± 0.015 m/s), whichever is greater

3

: ± 0.5 °F (± 0.3 °C)

4

: 0.1 to 195,000 l/s, 0.0424 to 702,000

3

/hr, 0.2 to 2,700,000 ft3/min

m

25

DUCT SIZE:

Range: 1 to 100 inches in increments of

RELATIVE HUMIDITY (MODELS 8347/8347A):

Range: 0 to 95% RH
Accuracy
Resolution: 0.1% RH

WET BULB TEMPERATURE (MODELS 8347/8347A)

Range: 40 to 140°F (5 to 60°C)
Resolution: 0.1°F (0.1°C)

DEW POINT (MODEL 8347/8347A):

Range: 5 to 120°F (-15 to 49°C)
Resolution: 0.1°F (0.1°C)

AVERAGING CAPABILITY:

Range: Up to 255 values of each velocity (or

TIME CONSTANT:

Range: Adjustable from 1 to 20 seconds

RESPONSE TIME:

To velocity: 200 msec
To temperature

5

: ±3% RH

8345/46: 8 seconds
8347/47A: 34 seconds

0.5 inches, 100 to 255 inches in
increments of 1 inch (1 to 100 cm in
increments of 0.5 cm, 100 to 255 cm
in increments of 1 cm)

flowrate), temperature, humidity, dew
point temperature, and wet bulb
temperature

26 Appendix A

EXTERNAL METER DIMENSIONS:

Size measurements: 3.9 in. x 6.6 in. x 1.5 in.

(10 cm x 16.8 cm x 3.8 cm)

METER PROBE DIMENSIONS:

Probe length (8345): 37 in. (94 cm) telescopic
Probe length (8346): 37 in. (94 cm) telescopic articulating
Probe length (8347): 40 in. (102 cm) telescopic
Probe length (8347A): 40 in. (102 cm) telescopic articulating

METER WEIGHT DIMENSIONS:

Weight (with batteries): 1.1 lbs (0.5 kg)

METER DISPLAY DIMENSIONS:

Display: 4-digit LCD, 0.6 in. (15 mm) digit

height

POWER REQUIREMENTS:
Four AA-size batteries (included) or AC adapter (optional)

PRINTER INTERFACE:

Type: Serial
Baud Rate: 1200

1

Temperature compensated over an air temperature range of

40 to 150 °F (5 to 65 °C).

2

The accuracy statement of ± 3 ft/min (± 0.015 m/s), applies

to 30 ft/min through 6,000 ft/min.

3

Accuracy with instrument case at 77 °F (25 °C), add

uncertainty of 0.05 °F/°F (0.03 °C/°C) for change in
instrument temperature. Deleted RF statement here.

4

Actual range is a function of maximum velocity and duct

size.

5

Accuracy with probe at 77°F(25°C). Add uncertainty of

0.1% RH/°F (0.2% RH/°C) for change in probe temperature.
Includes 1% hysteresis.

Specifications 27

Appendix B

DIP Switch Settings

To access the DIP switches, remove the batteries
from the battery compartment. On the inside of the
battery compartment, there is a window with eight
DIP switches. The table below shows the functions
for each switch.

Caution: Make certain that power is turned off

before changing DIP switch settings.

ON

1

8

DIP SWITCH

Figure B - 1: DIP Switch Location

29

OFF

Switch Function OFF ON

1 Velocity ft/min &

ft

3

/min
2 Flow Rate* l/s m3/hr
3 Temperature Degrees

Fahrenheit
(°F)

4 Decimals “.” used in

printing

5 Auto off

disable

Automatic
power off

6 Sample data Data lost

on manual

power off
7 Reserved Reserved Reserved
8 Beep Beep

Disabled

The ON position is away from the batteries and
OFF is towards the batteries.
Always leave DIP switch #7 in the OFF position.

* To select flow rate to display l/s or m

switch #1 must be in the ON position.

m/s

Degrees
Celsius
(°C)
“,” used in
printing
Auto off
disabled
Data kept

Beep
Enabled

3

/hr, DIP

30 Appendix B

Appendix C

Standard Velocity vs. Actual
Velocity

Since thermal air velocity sensors are sensitive to
changes in air density and air velocity, all thermal
anemometers indicate velocities with reference to a
set of standard conditions. For TSI instruments,
standard conditions are defined as 70° F (21.1° C)
and 14.7 psia (101.4 kPa). Other manufacturers
may use different values.

Standard velocity is the velocity the air would be
moving if the temperature and pressure were at
standard conditions. It is usually the most useful
measure of airflow because it defines the heat­carrying capacity of the air.

Actual velocity is the velocity at which a
microscopic particle of dust would be traveling if it
were in the air stream.

In some instances, actual air velocity rather than
standard velocity may be of interest. To obtain the
value for actual velocity, multiply your standard
velocity by the following density correction factor:

31

+







460

ActualVelocity

()

Standard Velocity

=




460 70

Where

T = Ambient temperature in degrees Fahrenheit

P = Ambient pressure in psia

If you use metric units, the equation becomes:

ActualVelocity (Standard elocity) =

V

273



273 211

Where

Tm = Ambient temperature in degrees Celsius

Pm = Ambient pressure in kPa

14 7

T









+







m

101..4

T

+



P

+



.




P



m

32

Appendix C







Example No. 1:

You want to measure the actual velocity in a duct.
The air temperature in the duct is 55°F and the
pressure is 14.24 psia. You take a measurement
and the display reads 1200 feet per minute (ft/min).

ActualVelocity =

460 55





460 70

Example No. 2:

You need to measure the actual velocity in a
plenum. The air pressure is 99.4 kPa and the
temperature is 27°C. The display reading is 2.3
meters per second (m/s).

ActualVelocity 2.3 =

273 27



273 21 1

14 7

+

+

+

.



=1200

1203 7

.4

.4

. ft/min

239

./ms

=





14 24

.



101

+



99

.



Standard Velocity vs. Actual Velocity

33

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