Testo Instruments 420 User manual

testo 420 ·Differential Pressure Instrument

Instruction manual

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

1 Contents

1 Contents

1 Contents ................................................................................................... 3

2 Safety and the environment .................................................................... 4

2.1. About this document ........................................................................ 4

2.2. Ensure safety ................................................................................... 5

2.3. Protecting the environment .............................................................. 6

3 Specifications .......................................................................................... 6

4 Technical data .......................................................................................... 6

5 Product description ................................................................................. 9

5.1. Overview.......................................................................................... 9

6 First steps .............................................................................................. 11

7 Using the product .................................................................................. 13

7.1. Switching Bluetooth® on and off.................................................... 13

7.2. Settings for the measurement ........................................................ 14

7.2.1. Damping (Gliding Average) ............................................................................ 14

7.2.2. Hood Calibration ............................................................................................ 14

7.2.3. Zeroing Interval (Automatic Zeroing) .............................................................. 14

7.3. Measuring ...................................................................................... 14

7.3.1. Pitot tube measurement ................................................................................. 14

7.3.2. Differential pressure measurement ................................................................ 15

7.4. Saving ........................................................................................... 15

7.5. Transferring measurement data to the PC .................................... 16

8 Maintaining the product ........................................................................ 17

8.1. Cleaning the instrument ................................................................. 17

9 Tips and assistance ............................................................................... 17

9.1. Questions and answers ................................................................. 17

9.2. Accessories and spare parts ......................................................... 18

10 Authorizations ........................................................................................ 19

3

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

2 Safety and the environment

2 Safety and the environment

2.1. About this document

Use

> Please read this documentation through carefully and

familiarize yourself with the product before putting it to use. Pay
particular attention to the safety instructions and warning advice
in order to prevent injuries and damage to the products.

> Keep this document to hand so that you can refer to it when

necessary.

> Hand this documentation on to any subsequent users of the

product.

Symbols and writing standards

Representation Explanation

Warning advice, risk level according to the
signal word:

Warning! Serious physical injury may occur.
Caution! Slight physical injury or damage to

the equipment may occur.
> Implement the specified precautionary

measures.

Note: Basic or further information.

1. ...

2. ...

Action: more steps, the sequence must be
followed.

> ... Action: a step or an optional step.

- ... Result of an action.

Menu Elements of the instrument, the instrument

display or the program interface.

[OK] Control keys of the instrument or buttons of

the program interface.

... | ... Functions/paths within a menu.

“...” Example entries

4

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

2.2. Ensure safety

> Do not operate the instrument if there are signs of damage at

the housing, mains unit or feed lines.

> Do not perform contact measurements on non-insulated, live

parts.

> Do not store the product together with solvents. Do not use any

desiccants.

> Carry out only the maintenance and repair work on this

instrument that is described in the documentation. Follow the
prescribed steps exactly. Use only original spare parts
from Testo.

> Dangers may also arise from the systems being measured or

the measuring environment: Note the safety regulations valid in
your area when performing the measurements.

Testo guarantees the functionality of its products when used in
accordance with their intended purpose. This guarantee does not apply
to features of Testo products in combination with unauthorised third­party products. Competitor products are not authorised by Testo.

As is common practice, Testo generally excludes support, warranty or
guarantee claims relating to functionality that has not been guaranteed
by Testo as part of the product offered. Claims shall also be excluded
in the event of improper use or handling of the products, e.g. in
combination with unauthorised third-party products.

2 Safety and the environment

For products with Bluetooth®

Changes or modifications that have been made without the explicit
consent of the responsible approval authority, may cause the
retraction of the type approval.

Data transfer may be disturbed by equipment that uses the same
ISM-band, e.g. WLAN, microwave ovens, ZigBee.

The use of radio communication links is not permitted in aeroplanes
and hospitals, among others. For this reason the following points
must be ensured before entering:

> Switch off the instrument.
> Disconnect control unit from all external power sources (mains

cable, external rech. batts., ...).

5

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

4 Technical data

2.3. Protecting the environment

> Dispose of faulty rechargeable batteries/spent batteries in

accordance with the valid legal specifications.

> At the end of its useful life, send the product to the separate

collection for electric and electronic devices (observe local

3 Specifications

regulations)

The testo 420 is used for volume flow measurements (main
application), Pitot tube measurements and pressure measurements
for air conditioning and ventilation systems. Thanks to its
interchangeable flow hoods, the testo 420 can be used for air inlets
and outlets of various sizes.

With the additional App (Android/iOS), the readings can be
conveniently displayed on a tablet or smartphone, and in addition a

4 Technical data

measurement can be started, stopped and saved via the App.

The use of the wireless module is subject to the regulations and
stipulations of the respective country of use, and the module may only
be used in countries for which a country certification has been granted.
The user and every owner has the obligation to adhere to these
regulations and prerequisites for use, and acknowledges that the re­sale, export, import etc. in particular in countries without wireless
permits, is his responsibility.

Feature Values

Measurement
parameters

Flow velocity : m/s / ft/min
Volume flow: m³/h / cfm / l/s
Pressure (absolute pressure): hPa / mbar / kPa
Pressure (differential pressure): Pa / hPa /

mbar / mmH

O / inH2O

2

Measuring cycle 1/sec

Interfaces Probe interface Mini DIN (testo 420 Set)

Micro USB

6

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

Feature Values

Measuring ranges Flow velocity: 0 to 14 m/s /

0 to 2750 ft/min

Pressure (absolute pressure):
700 to 1100 hPa

Pressure (differential pressure): ­120 to +120 Pa

Resolution Flow velocity: 0.01 m/s

Volume flow: 1 m³/h / 1 cfm
Pressure (absolute pressure): 0.1 hPa /

0.1 mbar / 0.01 kPa
Pressure (differential pressure): 0.001 Pa /

0.00001 hPa / 0.00001 mbar / 0.0001 mm
H2O / 0.000001 inH2O

Accuracy
(nominal temperatur
e 22°C/71.6°F)

Flow velocity and Volume flow: no accuracy
specification since calculated variable

Error absolute pressure compensation:
±0.04% of m.v. / hPa deviating from 1013 hPa

Pressure (absolute pressure): ± 3 hPa

Pressure (differential pressure): ±2% of m.v.
+ 0.5 Pa (at 22°C, 1013 hPa)

Error absolute pressure compensation:
±0.04% of m.v. / hPa deviating from 1013 hPa

Temperature
coefficient

Pressure (absolute pressure): ± 0.02% of
m.v. / K (deviating from 22 °C, in the range
0 to 60 °C)

Pressure (differential pressure): ± 0.02% of
m.v. / K (deviating from 22 °C, in the range
0 to 60 °C)

Response time t90 Flow velocity: approx. 1 s

Volume flow: approx. 1 s
Pressure (absolute pressure): approx. 1 s
Pressure (differential pressure): approx. 1 s

4 Technical data

7

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

4 Technical data

Feature Values

Operating and
ambient conditions

Storage temperature: -20 to +60 °C / -4 to
140 °F

Operating temperature: -5 to +50 °C/+23 ­+122°F

Humidity: 0 to 100% RH
Pressure range: 800 to 1100 hPa

Housing /
measurement setup

Measuring instrument housing material: ABS
Measuring instrument dimensions:

150x85x35 mm

Power supply

4 x 1.5 V rechargeable/non-rechargeable
batteries

Type AA / alkaline manganese, mignon
Battery lifetime: approx. 40h (eroing interval

10 seconds, display illumination off,
Bluetooth off)

Display Type: Dot matrix

Dimensions: 3.5 inches

Directives,

EU guideline: 2014/30/EU

standards and tests

8

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

5 Product description

5.1. Overview

Overview of testo 420

5 Product description

1 Battery compartment, on rear of the instrument
2 Display
3 Control keys
4 Probe socket Mini-DIN (only for use on the measurement base)
5 Micro-USB port
6 Connection for pressure measurement

Instrument status icons:

Icon Meaning

/ /

Battery capacity

Bluetooth

Measuring mode:
Pressure measurement, Pitot tube, volume

flow (air pressure from above into the hood /
suction outlet)

9

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

5 Product description

Icon Meaning

Actual

Standard

K-factor

Pitot Tube factor

(P-factor)

Actual volume flow:
The current ambient conditions are used to

calculate the volume flow. The actual
barometric pressure is measured with the
internal sensor. In applications with volume
flow hood, the temperature is measured by
the integrated temperature/humidity sensor,
with Pitot tube measurement the actual
temperature needs to be input manually.

Standard volumetric flow:
The standard settings for temperature and

barometric pressure (21 °C / 1013 hPa in
accordance with the standard conditions of
the NIST, National Institute of Standards and
Technology) are used to calculate the volume
flow.

Factor by which the current reading is
multiplied. Depends on which outlet
measurements are being taken at.

The Pitot tube factor for Pitot tubes is
generally the same and must be entered:

• Pitot tubes from Testo: 1.00

• Pitot tubes from other manufacturers: the
Pitot tube factor can be found in the
instruction manual or you should ask your
supplier.

10

Control keys

Key Function

[►, ■] Holds / starts / stops a measurement

[ESC]

[►, ▲, ▼,◄] Navigation within the menu

[]

Menu

Switches to the previous view / to the
measurement view

Saves the measured values

Confirms a selection

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

Key Function

6 First steps

Inserting batteries/rechargeable batteries

1. Open the battery compartment.

2. Insert the batteries or rechargeable batteries (scope of delivery
includes 4x 1.5V Type AA/ LR6).

3. Close the battery compartment.

When not in use for a long period of time, take the
batteries/rechargeable batteries out.

Implementing settings

1. Press to access the menu.

2. Select the menu item you require using ►, ▲, ▼, ◄.

Key functions

Display Explanation

►, ▲, ▼,◄ Change parameter, select unit

6 First steps

Switch instrument on/off (press and hold
down)

Switch illumination on/off (press briefly)

Confirm input

1. Menu Level 2. Menu Level 3. Menu Level

Application Flow Hood K-factor

Actual/Standard

Pitot tube Duct

Pitot tube factor

Pitot Temperature

Actual/Standard

Pressure only --

11

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

6 First steps

1. Menu Level 2. Menu Level 3. Menu Level

Measuring Program Single Measurment --

Continous
Measurement

1

Continous/Punctual

--

measuring duration
measurement (nur für
Staurohr)

Memory New Folder --

T420 folder --

Display Volume Flow on/off

Diff.Pressure on/off

Temperature on/off

Velocity on/off

Humidity on/off

Abs.Pressure on/off

Device Settings Language

English/German/Italia

n/French/Spanish

Backlight Auto Off On/Off

Auto Off On/Of

Bluetooth On/Off

Date&Time Date Format

Time Format

Set Date&Time

Gliding average 5 – 20 sec

Hood adjustment Supply Air

Exhaust Air

Zeroing int 1-20 sec

Reset Device -- --

2

1

Maximum of 15 minutes, measuring cycle 1 second

2

Maximum of 25 points and 1 minute per point.

12

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

7 Using the product

7.1. Switching Bluetooth® on and off

In order to be able to establish a connection via Bluetooth,
you need a tablet or smartphone with the Testo App testo
420 already installed on it.

You can get the App for iOS instruments in the App Store
or for Android instruments in the Play Store.

Information about compatibility can be found in the relevant
App Store.

Measurements can be performed and saved with App into
the instruments memory. Measuring mode and save
function on the instrument itself is not available during
Bluetooth communication is established with a mobile
device.

Switching on Bluetooth

1. Hold ▲ down for 3 seconds.

- Once the Bluetooth icon is shown on the display, Bluetooth is
switched on.

- If no connection is established, Bluetooth switches off after 10
mins. 

or

1. Press -> Device Settings -> Bluetooth, ► and using ▲/▼

-> select Off. Confirm with .

- Once the Bluetooth icon is shown on the display,
Bluetooth is switched on.

- If no connection is established, Bluetooth switches off after 10
mins. 



Display Explanation

flashes

is permanently

There is no Bluetooth connection, or a
potential connection is being searched for.

There is a Bluetooth connection.

displayed

is not displayed

Bluetooth is disabled.

7 Using the product

13

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

7 Using the product

7.2. Settings for the measurement

7.2.1. Damping (Gliding Average)

If the readings fluctuate widely, it is advisable to damp the
readings. The time range for the damping can be set manually
between 5-20 seconds.

1. Press , then select Device settings and Gliding average.

- The damping can be set between 5-20 seconds.

7.2.2. Hood Calibration

This input is provided for the filing of calibration data by the relevant
calibration laboratory. The flow hood-specific adjustment data can
be input manually for supply air and exhaust air and has a direct
effect on the measurement results. Input option of 0.001-9.999.

1. Press , then select Device settings and Hood adjustment.

- Calibration of the hood can be set for supply air and exhaust air.

7.2.3. Zeroing Interval (Automatic Zeroing)

The pressure sensor carries out automatic zeroing at regular
intervals. These intervals can be set via the automatic zeroing.

1. Press , then select Device settings and Zeroing int.

- The zeroing interval can be set between 1-20 seconds.

7.3. Measuring

7.3.1. Pitot tube measurement

1. Connect the hoses to the testo 420 and to the Pitot tube.

2. Press -> Application -> Pitot tube and there set the duct

geometry, the Pitot tube factor and the temperature, and
choose between actual and standard.

3. Select the required measurement program.

4. Carry out the measurement.

With a timed/multi-point measurement program, the
required number of measuring points can be recorded
using [►, ■]. To end the measurement, press and hold
down [►, ■] for at least 3 s. At least one measuring point
must be recorded before the measurement can be
terminated.

14

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

5. Press to save the measurement data. Unsaved
measurement data is lost once you carry out the next
measurement.

- The target folder and file name are displayed, confirm with
to save the measurement data under this name and in the
selected folder.

The Pitot tube factor for Pitot tubes is generally the same
and must be entered:

Pitot tubes from Testo, Pitot tube factor: 1.00
Straight Pitot tubes from Testo, Pitot tube factor: 0.67
Air flow velocity matrix 0699.7077, Pitot tube factor: 0.82
For Pitot tubes from other manufacturers, refer to the

instruction manual for the Pitot tube factor or ask your
supplier.

7.3.2. Differential pressure measurement

1. Connect the hoses to the testo 420 at + and -.

2. Press -> Application -> Pressure only.

3. Carry out the measurement.

4. Press to save the measurement data. Unsaved
measurement data is lost once you carry out the next
measurement.

- The target folder and file name are displayed, confirm with
to save the measurement data under this name and in the
selected folder.

7 Using the product

7.4. Saving

A maximum of 99 measurements can be saved in one
folder.

> -> Memory ->

- The folder overview is shown on the display. Create a new
folder via New Folder.

A maximum 100 folders can be created.

Open folder

> Using the arrow keys, navigate to the required folder and press

.

- The selected folder is opened and the individual files are
displayed.

15

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

7 Using the product

Delete folder

1. Using the arrow keys, navigate to the required folder and press

.

2. Select the menu item Delete Folder and confirm with .

- The folder that you want to delete is shown on the display.

3. Confirm once again with in order to delete the folder,

or cancel by pressing Esc.

Set as Logging Folder

This setting establishes which folder is to be specified as the
standard storage location for saving the measurements.

The folder which is set as the standard storage location is
marked in black.

1. Using the arrow keys, navigate to the required folder and press

.

2. Select the menu item Set as Logging Folder and confirm with

.

- The selected folder is set as the standard storage location.

- The stored location can be changed during the saving process.

7.5. Transferring measurement data to the PC

No Bluetooth connection is possible while there is a
connection to the PC. The existing Bluetooth connection is
aborted.

The PC identifies the testo 420 as a removable medium. In
the event of any formatting, please make sure that the FAT
format is always selected under the file system.

1. Connect the testo 420 to your PC using the USB cable.

- The testo 420 switches on automatically, a window appears on

the PC, select Open folder here. The folders and files saved on
your testo 420 are displayed. The files are available in the file
format *.txt.

16

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

8 Maintaining the product

8.1. Cleaning the instrument

Do not use any aggressive cleaning agents or solvents!
Mild household cleaning agents or soap suds may be used.

> If the housing of the instrument is dirty, clean it with a damp

9 Tips and assistance

9.1. Questions and answers

cloth.

Question Possible causes/solution

For selected parameters,
no values are shown on

No temperature/humidity probe is

connected, for instance.
the instrument display
(-----)

Warning message Can not

turn on! when selecting

certain parameters in the
Display menu.

• This parameter is not available for
the application currently selected.

• Four parameters are already
displayed. Disable the display of
one parameter to enable another
one.

• [►, ■] on the
instrument does not
work.

• Warning message

Function not
available in Bluetooth

• Bluetooth connection is active, the
instrument is connected to a Tablet
or Smartphone via Bluetooth and
the App is active.

• Fully close the App or end the
Bluetooth connection.

mode.

9 Tips and assistance

17

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

9 Tips and assistance

9.2. Accessories and spare parts

Description Article no.

Connection hose, silicone, length 5 m,
maximum load capacity 700 hPa (mbar)

Connection hose, silicone-free, for differential
pressure measurement, length 5 m,
maximum load capacity 700 hPa (mbar)

Pitot tube, length 500 mm, Ø 7 mm, stainless
steel, for measuring flow velocity
(Connection hose required)

Pitot tube, length 350 mm, Ø 7 mm,
stainless steel, for measuring flow velocity
(Connection hose required)

Pitot tube, 1,000 mm long, stainless steel,
measures flow velocity
(Connection hose required)

Connection hose 0554 0453

For a complete list of all accessories and spare parts, please refer

to the product catalogues and brochures
If you have any questions, please contact your dealer.

0554 0440

0554 0453

0635 2045

0635 2145

0635 2345

18

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

10 Authorizations

Please note the following country-specific information for the
product authorization.

Product

Testo 420

10 Authorizations

Mat.-No.

Country Comments

Australia

New
Zealand

Turkey Authorized

Canada Product IC ID: 12231A-05600420

China CMIIT ID: 2015DP4400

USA Product FCC ID: 2ACVD05600420

Korea

0560 0420

RCM mark Supplier identification

Authorized

IC Warnings

FCC Warnings

MSIP-CMM-Toi-420

KCC Warning

E1561

South
Africa

19

Find Quality Products Online at: [e-mail]

Radio Equipment Type approval numer: TA-2016/3100

www.GlobalTestSupply.com

10 Authorizations

Europa +
EFTA

Japan Radio

Brazil

EU

countries:

Belgium (BE), Bulgaria (BG), Denmark (DK), Germany (DE), Estonia (EE), Finland
(FI), France (FR), Greece (GR), Ireland (IE), Italy (IT), Latvia (LV), Lithuania (LT),
Luxembourg (LU), Malta (MT), Netherlands (NL), Austria (AT), Poland (PL),
Portugal (PT), Romania (RO), Sweden (SE), Slovakia (SK), Slovenia (SI), Spain
(ES), Czech Republic (CZ), Hungary (HU), United Kingdom (GB), Republic of
Cyprus (CY).

EFTA countries:

Iceland, Liechtenstein, Norway, Switzerland

Japan Information

201-150304

Este equipamento opera em caráter secundário, isto é,

não tem direito à proteção contra interferência prejudicial,

mesmo de estações do mesmo tipo e não pode causar

interferência a sistemas operando em caráter primário.

Taiwan NCC: CCAB16LP2190T1

20

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

10 Authorizations

Bluetooth
SIG List

Feature Values

Bluetooth® Range 15 m (free field)

(varies with the used mobile device)

Bluetooth® type

LSD Science & Technology Co., Ltd

L Series BLE Module (08 Mai 2013) based on TI
CC254X chip

Qualified
Design ID

B016552

Bluetooth® radio class Class 3

Bluetooth® company ID 10274

IC Warnings

This instrument complies with Part 15C of the FCC Rules and Industry Canada RSS­210 (revision 8). Commissioning is subject to the following two conditions:

(1) This instrument must not cause any harmful interference and

(2) this instrument must be able to cope with interference, even if

this has undesirable effects on operation.

Cet appareil satisfait à la partie 15C des directives FCC et au standard Industrie
Canada RSS-210 (révision 8). Sa mise en service est soumise aux deux conditions
suivantes :

(1) cet appareil ne doit causer aucune interférence dangereuse et

(2) cet appareil doit supporter toute interférence, y compris des interférences qui
provoquerait des opérations indésirables.

FCC Warnings

Information from the FCC (Federal Communications Commission)

For your own safety

Shielded cables should be used for a composite interface. This is to ensure continued
protection against radio frequency interference.

FCC warning statement

This equipment has been tested and found to comply with the limits for a Class C
digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to
provide reasonable protection against harmful interference in a residential installation.
This equipment generates, uses and can radiate radio frequency energy and, if not
installed and used in accordance with the instructions, may cause harmful interference
to radio communications. However, there is no guarantee that interference will not
occur in a particular installation. If this equipment does cause harmful interference to
radio or television reception, which can be determined by turning the equipment off and
on, the user is encouraged to try to correct the interference by one or more of the
following measures:

• Reorient or relocate the receiving antenna.

• Increase the separation between the equipment and receiver.

• Connect the equipment into an outlet on a circuit different from that to which the
receiver is connected.

• Consult the dealer or an experienced radio/TV technician for help.

21

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com

10 Authorizations

Caution

Changes or modifications not expressly approved by the party responsible for
compliance could void the user's authority to operate the equipment. Shielded interface
cable must be used in order to comply with the emission limits.

Warning

This device complies with Part 15 of the FCC Rules.

Operation is subject to the following two conditions:

(1) this device may not cause harmful interference, and

(2) this device must accept any interference received,

including interference that may cause undesired operation.

KCC Warning

해당 무선 설비는 운용 중 전파혼신 가능성이 있음

Japan Information

当該機器には電波法に基づく、技術基準適合証明等を受けた特定無線設備を装着してい
る。

22

Find Quality Products Online at: [e-mail]

www.GlobalTestSupply.com