TESTO 454 User manual

testo
testo 454
Data logger
Instruction Manual
testo
454
Logger
testo
0
123
456
789
•
Aus
Off
Ein
On
Enter /
10...14V DC
TESTO
QUALITY
I
S
O
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1
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Contents
1Applications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2Description of instrument. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4Keyboard layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.1 Hot keys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5Menu overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6Introductory training
6.1 Measuring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
6.2 Printing the measured values on the infrared printer . . . . . 11
6.3 Saving measured values . . . . . . . . . . . . . . . . . . . . . . . . . . 11
6.4 Setting up a location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
7Operating instructions
7.1 Measuring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
8Main menu
8.1 Averaging. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
8.2 Mean value configuration. . . . . . . . . . . . . . . . . . . . . . . 15
8.3 Memory
8.3.1 View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8.3.2 State. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8.3.3 Programs 1 - 3
8.3.3.1 Starting criterium . . . . . . . . . . . . . . . . . . . . . . . . . . 18
8.3.3.2 Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
8.3.3.3 Activating duration and program. . . . . . . . . . . . . . . 21
8.3.3.4 Overview of the programming system . . . . . . . . . . 22
8.3.4 Minimimum rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
8.3.5 Keylock. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
8.3.6 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
8.4 Print . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
8.5 Location
8.5.1 Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
8.5.2 Enter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
8.5.3 Erase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
8.6 Device
8.6.1 Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
8.6.2 Date/Time. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
8.6.3 Rechargeable battery. . . . . . . . . . . . . . . . . . . . . . . . . . 25
8.6.3.1 Notes on battery operation. . . . . . . . . . . . . . . . . . . . . . 25
8.6.3.2 Examples for rechargeable battery lifetime . . . . . . . . . 25
8.6.4 Auto-Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
8.6.5 Intermediate rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
8.6.6 Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
8.6.7 Units. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
8.7 Probes
8.7.1 Unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
8.7.2 Scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
8.7.3 Calibrate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
8.7.4 Adjust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
8.7.5 Discard. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
8.8 Specials
8.8.1 Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
8.8.2 Flow volume. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
8.8.3 Density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
8.8.4 Pressure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
2

testo 454 -The handy measuring instrument
Nearly all of the probes from the Testo range can be connected to the universal hand-held
instrument. The automatic probe recognition function facilitates quick control measure-
ments. In air conditioning technology several parameters can be quickly measured on
location e.g. temperature, humidity, velocity and pressure. The probe designs are fully
adapted to the respective applications.
testo 454 - The powerful data logger
All of the boundary conditions for an independent long-term measurement are program-
mable: start of measurement, end of measurement, location name and alarm outputs are
determined by selectable starting criteria. The six freely assignable channels and three
measuring programs make the data logger very versatile. There are various additional spe-
cial functions available for air conditioning and ventilation technology: averaging, volume
flow display, Pitot tube calculation etc.
testo 454 - Independent application
The rechargeable, environment friendly rechargeable battery makes the user independent
of the power supply. Power can also be supplied from a car battery.
testo 454 - User-friendly operation
The housing is ergonomic and ideal for practical operation and is made of robust ABS.
The large, illuminated display can be easily read and can display three different parame-
ters. The menu-driven user operation via the sealed keyboard makes the instrument easy
to use.
testo 454 - Configuring and data processing on the PC
If a PC and the Comfort software are connected you can take full advantage of the benefits
offered by the data logger. All of the settings in the data logger are prepared first in the PC
and are then loaded into the data logger. Only the measurement is started on the measur-
ing location. The processing of saved measured in the PC is just as uncomplicated as con-
figuring.
Contents
9Error messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
10 Technical data
10.1 Measuring instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
10.2 Infrared printer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
10.3 Comfort software - 454 module . . . . . . . . . . . . . . . . . . . . . 35
10.4 Probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
10.4.1 Connection cables for probes . . . . . . . . . . . . . . . . . . . . . . 40
11 Ordering data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
12 Warranty conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Probe description - Measuring technology. . . . . . . . . . . . . Appendix
1Applications
3

testo
2Description of instrument
4
testo
454
Logger
testo
0
123
456
789
•
Aus
Off
Ein
On
Enter /
10...14V DC
Top of housing
with protective cover for PC inter-
face and alarm/trigger interface.
Display with 4 lines.
6 probe inputs
Assignment is freely selectable,
the instrument recognises the
probes connected by way of a
special code. See label on the
back for socket assignment.
Keyboard
The keyboard commands are
described in the Chapter “Key-
board layout”.
Mains connection
Measuring instrument conforms with
EN 50 082-1 / EN 55 011 Group 1 Class A

RS/232 Trigger/Alarm
2Description of instrument
5
Trigger/alarm connection for
alarm/ trigger connection cable
0554.0012
Infrared diode for transferring
data to the infrared printer. The
cover does not need to be
removed before printing.
RS/232 interface for connection
to the PC.
3Warning
Please read before using instrument
Do not measure on live parts.
Observe permissible storage and transport temperatures and the permissible oper-
ating temperature (e.g. protect measuring instrument from direct sunlight)!
Switch off the instrument when changing the configuration (e.g. probe change, plug-
ging in the V24 cable) because the values specific to the probes can only be read
after the instrument is switched on.
If the instrument is opened, improperly handled or force is used the warranty rights
are cancelled.
In the case of temperature probes which come into contact with metal, there may
be an electric discharge caused by the different potential between metal and the
surface probe. Please apply adhesive tape to the point of measurement during
this type of application. In this way a discharge which could limit the functioning
of the instrument is preventde.

testo
4Keyboard layout
6
Text Function
<Enter> Switches on instrument
Opens selected menu
Confirm entry
<Up> Moves cursor ( ˛ ) upward in the display
Scrolls display
Selects letters
<Down> Moves cursor ( ˛ ) downward in the display
Scrolls display
Selects letters
<Off> Switches off instrument
<Point> Decimal point
Hot key function
<Arrow> ESC key
Returns to a higher level
Inquiry on the hot key function (in the meas. menu)
<0>…<9> Enters numbers
Hot key function
Ein
On
Enter /
Aus
Off
•
0
9
…
Key

Key Text Text in display
Function when key is pressed
4Keyboard layout
7
Backl. (Backlight)
Background light on/off
P1 I/O
Start/stop programming 1
P2 I/O
Start/stop programming 2
P3 I/O
Start/stop programming 3
Location
Selects from list
View
Activates protocol overview
Print
Activates print menu
P1 set
Defines programming 1
P2 Set
Defines programming 2
P3 Set
Defines programming 3
Pkt.Msg (Point measurement)
Files single measuring blocks in the memory.
0
1
2
3
4
5
6
7
8
9
•
<Point>
<0>
<1>
<2>
<3>
<4>
<5>
<6>
<7>
<8>
<9>
Displays version number
•
<Point>+<Enter>
“Zeroizes” pressure probe
Ein
On
Enter /
Ein
On
Enter /
<Up>+<Enter>
Hot key functions are short commands which make it possible to activate submenus direct-
ly without having to select them by scrolling through the menu tree. The hot key functions,
marked with black bars ( ), are only active parallel to the measuring menu.
+
+
4.1 Hot keys

Multi-pt Mv
config. Memory Printing
Collecting values and
multi-pt Select parameter Set time window
0-> point mv
View
Scroll through
protocol headings
Call up meas. val.
in the memory
Current mv
Display is printed
Mode
Protocol
Protocol selection
Set program
I, II, III
Starting criterion
Rate
Duration
Activate
programs
Settings
Measuring
programs
Minimum rate
Keylock
Reset
Ein
On
Enter /
Ein
On
Enter /
Ein
On
Enter /
Ein
On
Enter /
Ein
On
Enter /
P.inactive
1: 26.4 %
1: 25.8 °C
1: 6.5td°
Ein
On
Enter /
Measuring menu
Ein
On
Enter /
•
Quit
Main menu
Cancel
Cancel printout
testo
8
8.1 8.3 8.48.2
State
Print
Values

Location
Selection
List of locations
Select location
Enter
Enter
number or
capital letters
Erase
Location
Ein
On
Enter /
Ein
On
Enter /
Ein
On
Enter /
Ein
On
Enter /
Display
Configure:
select parameters
Unit Speical function display
Automatic display
of derived values
Volume flow
Rd. cross-section
Sq. cross-
section
Density, manual
Absolute, manual
Date/Time
Displays/Correction
Rechargeable battery
Shows voltage
and capacity
Auto-Off
Activate
Deactivate
Intermediate rate
Enter rate
Alarm I
Configure
Activate
Units
Instrument Probe Special
function
Alarm Il
Configure
Activate
Scale
Calibration
Selection
Erase
5Menu overview
9
8.5 8.6 8.7 8.8
Select
Device Probes
Scaling
Calibrate
Adjust
Discard
Specials
Flow volume
Pressure

testo
454
Logger
testo
0
123
456
9
•
10...14V DC
Ein
On
Enter /
˛˛˛˛˛˛˛˛˛˛
˛˛˛˛˛˛˛˛˛˛
˛˛˛˛˛˛˛˛˛˛
˛˛˛˛˛˛˛˛˛3
P.inactive
1: 47.8 %
1: 23.4 °C
2: 47.8 %
testo
6Introductory training
The purpose of the introductory training is to make
the operation of the instrument easier for you.
Measuring, printing and saving is explained in short,
easy steps.
The functions of the testo 454 are described in
detail in Chapter 8.
Before using the instrument please check if the deliv-
ery is complete and undamaged.
6.1 Measuring
Connect one or more probes to the measuring instru-
ment.
Irrespective of which sockets are assigned the meas-
uring instrument recognises which sockets are
assigned and which probes are connected.
It is important that the probes are connected
before the instrument is switched on so that the
instrument can query the probe codes when switched
on.
Now switch on the measuring instrument.
A short function test is conducted. After several sec-
onds the instrument is in the measuring menu and
the first set of information appears in the display.
The code of the respective measuring program is dis-
played in the top line. “P inactive” means that a
measuring program was not activated (refer to Chap-
ter 8.3.3)
The measured values are shown in the lines below:
• the socket assignment is shown in the left
column
• the measured value is in the middle column
• the unit is in the right column
If you happen to go to the wrong menu when going
through the steps or if you simply do not know how to
proceed press the <Arrow> key several times and
you will return to the next highest menu and back to
the measuring menu.
10
P.inactive
2: 47.8 %
2: 23.4 °C

6Introductory training
From the measuring menu go to the submenu “Print”
by pressing the key <6>, selection is on “MEASURED
VALUES”.
Switch on the printer.
Position the printer and the measuring instrument
such that the red control lamp is pointing in the direc-
tion of the infrared diode in the testo 454 measur-
ing instrument.
Confirm the menu point selected “PRINT - MEASURED
VALUES” with <Enter>.
The printer immediately prints the current measured
values.
Ensure that the infrared connection from the
measuring instrument to the printer is not inter-
rupted during the printing otherwise you may have
an incomplete printout.
Go back to the measuring menu after printing by
pressing <Arrow> twice.
6.3 Saving measured values
Save the current measured values out of the measu-
ring menu via the <point> key.
“Act.Values stored Location: LENZKIRCH” appears
in the display. The location “LENZKIRCH” is set in
the factory. It is possible to change the measuring
location or to set up a selection of different locations
(see next page).
Return to the measuring menu by pressing <Enter>.
11
Print
Values
Protocol
Settings
6
P.inactive
1: 47.8 %
1: 23.4 °C
2: 47.8 %
•
Act.Values
stored
Location:
LENZKIRCH
Messwerte
01.01.94 03:27:18
3: 34.5 %
3: 23.3 °C
3: 6.8td°
4: 48.2 %
4: 23.3 °C
4: 11.8td°
Ein
On
Enter /
Ein
On
Enter /
P.inactive
1: 47.8 %
1: 23.4 °C
2: 47.8 %
0
12 3
45 6
78 9
•
Aus
Off
Ein
On
Enter /
Drucken
µesswerte
Protokoll
Einstell.
6.2 Printing the measured values on the infrared printer

Main menu
Memory
Print
¬ocation
>HA
å
B
C
Ein
On
Enter /
>H
F
G
ª
testo
6Introductory training
12
Main menu
µulti-pt
Mv config
Memory
Ein
On
Enter /
Ein
On
Enter /
Location
‚elect
Enter
Erase
Location
Select
™nter
Erase
>˛
A
B
Ein
On
Enter /
Ein
On
Enter /
1
Ein
On
Enter /
3
Ein
On
Enter /
6.4 Setting up a location
Change from the measuring menu to the main menu
by pressing <Enter>.
Move the cursor to “LOCATION” by pressing <down>
4 times and confirm by pressing <Enter>.
Select the submenu “ENTER” via the <down> key
and activate it by pressing the <Enter> key.
Now enter a location in this submenu with up to 9
characters.
Select letters via <up><down>; the letters confirmed
with <Enter> are written in the top line.
Numbers can be entered directly via the <0…9>
keys.
In order to save the location in the selection the top
line has to be filled right up to the 9th digit (e.g. with
blanks “_” ).

6Introductory training
6.4 Setting up a location
Confirm the input location with <Enter>.
You are again in the “Location” menu.
By pressing the <Arrow> key twice you go back to
the measuring menu via the main menu.
13
>HALL 13
˛
A
B
Ein
On
Enter /
Location
Select
™nter
Erase
Main menu
Memory
Print
¬ocation
P.inactive
1: 47.8 %
1: 23.4 °C
2: 47.8 %

7Operating instructions
7.1 Measuring
When measuring the probes must be connected
before the instrument is switched on.
Insert one or more probe plugs into the data logger
socket(s). It does not matter which socket you
choose as the data logger recognises the assign-
ment of the input channels and the probes conn-
ected.
Switch on the instrument.
A short function test is carried out.
The instrument then goes to the measuring menu.
A 4 line display appears.
The first line shows the program status, in this case
“P. inactive” for program inactive which means that a
measurement is not activated (activated programs
wait on the respective programmed starting criterion,
see Chapter 8.3.3).
The current measured values are shown in the fol-
lowing lines. The input channel (socket no.) is shown
in the left column while the current measured value is
shown in the right column.
Using <up>/<down> the measured values can be
scrolled up and down in the display (if more than 3
are active).
Leave the measuring menu by pressing <Enter> and
change to the main menu.
The main menu includes the following submenus:
Averaging Chapter 8.1
Mean value configuration Chapter 8.2
Memory Chapter 8.3
Print Chapter 8.4
Location Chapter 8.5
Device Chapter 8.6
Probes Chapter 8.7
Specials Chapter 8.8
14
testo
454
Logger
testo
0•
10...14V DC
Ein
On
Enter /
˛˛˛˛˛˛˛˛˛˛
˛˛˛˛˛˛˛˛˛˛
˛˛˛˛˛˛˛˛˛˛
˛˛˛˛˛˛˛˛˛3
P.inactive
1: 26.4 %
1: 25.8 °C
1: 6.5td°
P.inactive
1: 6.5td°
2: 48.8 %
2: 23.8 °C
Ein
On
Enter /
testo
Main menu
Multi-pt
Mv config
Memory
Main menu
Print
Location
Device
Main menu
Device
Probes
Specials

8Main menu
8.1 Averaging
The parameters, taken as a basis when averaging,
are defined by you in the menu point “MVCONFIG”.
A measuring rate of 1 second is the basis for averag-
ing. The time is defined in the menu “MVCONFIG”.
Select “MULTI-PT” from the main menu.
Measurement is started via the <Point> key.
The mask gives information on the
- remaining averaging time in seconds,
- number of averagings,
- parameter to be averaged (unit),
- current measured value,
- averaged measured value.
An averaging calculation which has been started can
be cancelled with the <Arrow> key and the measured
values are not saved. When leaving the menu by
pressing <Enter> the individual mean values and the
total mean values are automatically saved as a
protocol with the current location. Saved mean val-
ues can be called up in the menu “VIEW MEMORY”.
8.2 Mean value configuration
Open the “MVCONFIG” menu.
Select a channel (=Parameter) via <up>/<down>.
Confirm with <Enter>, the cursor jumps to the next
line.
Enter the duration of the averaging in seconds (three
digit value e.g. 030 ). Confirm with <Enter> and you
return to the main menu.
If you wish to check the entry or take an average
directly move the cursor via <up> to “MULTI-PT” and
confirm with <Enter>.
Proceed in the “MULTI-PT”menu as described above.
15
Main menu
Multi-pt
Mv config
Memory
Channel
∆1: %
Duration
10 s
Channel
∆2: °C
Duration
10 s
Ein
On
Enter /
Ein
On
Enter /
Channel
K1: %
Duration
˛10 s
Main menu
Multi-pt
µv config
Memory
Channel
K1: %
Duration
125 s
1
2
5
Ein
On
Enter /
Time 5 s
No 2 %
Act 27.7
Mv 26.9˛
Time s
No 0 %
Act 27.7˛
Mv
Ein
On
Enter /
•
.....

testo
8.3 Memory
8.3.1 View
All of the completed measuring programs and aver-
ages are saved in numerical order.
Via the menu point “MEMORY: VIEW”
an information mask appears which shows you the
number of protocols (“PROTOCOLS”) already available.
In the following masks you will see the protocol head-
ings of the saved protocols:
1st line: - Protocol number and measuring location
2nd line: - Number of measuring channels ( K or MW
in average protocols
- Number of measured values ( W )
3rd line: - Date
4th line: - Time (start of protocol)
Select a heading via the <up><down> keys and call it
up via <Enter>.
The 1st line of the protocol contains information on
the channel and the parameter of the listed meas-
ured values. The other channels are reached via
<Enter>.
You can scroll through the measuring protocol to the
last measuring value via <up><down> keys.
You can return to the “MEMORY: VIEW”menu by
pressing the <arrow> key.
8.3.2 State
Select the “STATE” menu point from the “MEMORY”.
The following display includes:
2nd line: - used kByte
3rd line: - free kByte
4th line: - free memory in %
Your testo 454 has a memory capacity of
224 kByte which corresponds to 110,000 measured
values. Return to the “MEMORY” menu by pressing the
<arrow> key and go to the measuring menu via
<Enter>.
8Main menu
16
Protocol
13
Main menu
Multi-pt
Mv config
µemory
Memory
√iew
State
Prog. I
Memory
√iew
State
Prog. I
1 Testo
12K, 120W
16.03.94
12:01:46
1°C
1 19.2
2 19.2
3 19.2
1°C
2 19.2
3 19.2
4 19.4
2%
1 31.6
2 31.9
3 32.1
2 Testo
MW % 3W
16.03.94
13:25:57
Ein
On
Enter /
Ein
On
Enter /
Ein
On
Enter /
Memory
View
‚tate
Prog.I
Memory
Used: 9kB
Rem:215kB
Free:93%
Ein
On
Enter /
Ein
On
Enter /
Ein
On
Enter /

8Main menu
8.3 Memory
8.3.3 Programs 1-3
Measurements can be controlled via 3 freely definable measuring/saving programs. The
channel, starting criteria, measuring rate, measurement duration or number of values are
defined in the programs 1-3. The programs are started once the “starting criterion” is ful-
filled. The starting criterion is checked at the measuring rate: if a slow rate has been set it
is advisable to set a an intermediate rate when checking the starting criterion (see Chapter
8.6.5). All 3 programs can be started independently of each other, they save all of the con-
nected probe values at the set measuring rate. “Programming 1” can be taken as an exam-
ple for all 3 programmings.
17
Example 1: Measurement with activated “Program 1”, Starting criterion: “Overrun”
Example 2: Measurement with two activated programs (Prog. 1 and Prog. 2),
Starting criteria: “Exceeding”
Display, channel 1
Display, channel 1
Time
Time
Limit value of
starting criterion
”Exceeding”
Limit of starting
criterion
“Exceeding”
Prog. 2
Limit of
starting criterion
“Exceeding”
Prog. 1
Prog.1
active
Prog. 2
active
Start of program 1 when
the programmed starting
criterion is entered
xxxxx =
Checking the
starting criterion
at a quicker rate
(“Device” menu,
“Intermediate
rate” submenu)
End of program 1, the starting
criterion is lifted
The program can be ended pre-
maturely via “Measuring rate” or
“Number of values
Progression of parameter at channel 1
Progression of parameter at channel 1
x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x
Prog.1
active
Changing measuring rate e.g. high
resolution in critical areas
Data acquisition corresponding to the
“Measuring rate”

testo
8 Main menu
Ein
On
Enter /
Ein
On
Enter /
Ein
On
Enter /
Ein
On
Enter /
Ein
On
Enter /
Ein
On
Enter /
Memory
View
State
πrog.I
Prog.Start
Ext.Signa
Prog.Start
Time
02.06.93
12:23:47
Prog.Start
Overrun
K1: %
+ 50.00
Prog.Start
Underrun
K1: %
+ 50.00
Prog.Start
Gradient
K1: %
5.00
8.3 Memory
8.3.3.1 Program starting criterion
Select a starting criterion:
External signal
The starting command is triggered when an external
voltage signal is input. Please use the lead
0554.0012 (See Ordering data) when inputting an
external voltage signal. In the case of a trigger circuit
the limit values of the trigger input must be adhered
to (Refer to Technical data). The trigger input in
testo 454 is electrically isolated from the other
circuit.
Time
The program start is made dependent on the date
and time. If the instrument is switched off the start is
delayed by approximately 5 seconds until the instru-
ment has completed the function test and probe rec-
ognition.
Overrun
Saving begins when the measured value of a param-
eter, defined by you, overruns on a channel specified
by you. An intermediate rate is recommended to
check the starting criterion frequently (see Chap.
8.6.5).
Underrun
Saving begins when the measured value of a param-
eter, defined by you, underruns on a channel speci-
fied by you. An intermediate rate is recommended to
check the starting criterion frequently (see Chap.
8.6.5).
Gradient
The program is started once the measured value of a
specified parameter in the defined channel changes
quicker than that of the limit value defined by you.
The specified value refers to:
∆t = 1 s
The display opposite means that
the program is started when the measured value
changes by more than 5 %RH in 1 second.
Difference
When the differential value (of a parameter) in two of
the channels specified by you is overrun measure-
ment is started. If, for example, the temperature of
K1 is 50 °C below that of K2 the program is started.
∆<w>
∆t
Programm
Rate
˛1s
Prog.Start
Difference
K2: °C -K1
25.00
Ein
On
Enter /
18

8 Main menu
8.3 Memory
Note on the differential trigger programming in
combined probes:
If combined probes are used for the starting criterion
“Difference” there is not enough space in line 3 of the
display to show clearly the channel and the parame-
ter.
In the 3rd line of the display opposite only “K2”
appears at the end of the line. The parameter is allo-
cated correctly by numbering the key confirmations
of <up> <down>.
The confirmation of a starting criterion via <Enter>
triggers a jump to the"PROGRAM RATE" parameter.
Prog.Start
Difference
K2: °C -K2
10.00
19
Note:
The program end criterion is delayed in relation
to the programmed start limit value (hysteresis):
the program continues saving for a short time
even though the programmed limit value is no
longer overrun.

testo
8.3 Memory
8.3.3.2 Rate
Specify the rate at which the measuring instrument
should save the probe data during this measurement.
Entries from 0.1 seconds to 24 hours are possible.
Seconds can be given in fractions. Minutes and hour-
ly rates are usually whole numbers. All values are
saved according to the probes connected.
8Main menu
20
Program
Rate
˛1s
Ein
On
Enter /
Please note that some measuring time must be
allowed for each connected probe since the sockets
must be serially checked.
The probe with the longest measuring time
defines the minimum measuring rate.
The following is the time required for each probe:
Hum. probe °C/%RH w. dew-point .0.3 seconds
Vanes . . . . . . . . . . . . . . . . . . . . . . . .0.7 seconds
Shell anemometer . . . . . . . . . . . . . .2.2 seconds
Frequency sources . . . . . . . . . . . . .0.7 seconds
Pt100 probes . . . . . . . . . . . . . . . . .0.1 seconds
Other . . . . . . . . . . . . . . . . . . . . . . . .0.2 seconds
In the menu MIN.RATE (See Chap. 8.3.4) the short-
est measuring rate depending on the probes con-
nected can be checked.
0