Bühler technologies Nivotemp NT-ELD User manual

FluidControl
Installation and Operation Instructions
Original instructions
Level switch
Nivotemp NT-ELD
BE100026
08/2017
Bühler Technologies GmbH, Harkortstr. 29, D-40880 Ratingen
Tel. [phone] / 49 89-0, Fax: [phone] / 49 89-20
E-Mail: [email protected]
Internet: www.buehler-technologies.com

Bühler Technologies GmbH, Harkortstr. 29, D-40880 Ratingen
Tel. [phone] / 49 89-0, Fax: [phone] / 49 89-20
Internet: www.buehler-technologies.com
E-Mail: [email protected]
Read this instruction carefully prior to installation and/or use. Pay at-
tention particularly to all advises and safety instructions to prevent in-
juries. Bühler Technologies can not be held responsible for misusing
the product or unreliable function due to unauthorised modifications.
All rights reserved. Bühler Technologies GmbH 2017
Document information
Document No..........................................................BE100026
Version......................................................................... 08/2017

Nivotemp NT-ELD
Contents
1 Introduction..................................................................................................................................................................................................................... 3
1.1 Intended Use......................................................................................................................................................................................................... 3
1.2 Functionality......................................................................................................................................................................................................... 3
1.2.1 Liquid level monitoring ......................................................................................................................................................................3
1.2.2 Temperature monitor .........................................................................................................................................................................3
1.3 Ordering instructions NT-ELD.......................................................................................................................................................................... 3
1.4 Scope of Delivery..................................................................................................................................................................................................4
2 Safety instructions......................................................................................................................................................................................................... 5
2.1 Important advice................................................................................................................................................................................................. 5
2.2 General hazard warnings ................................................................................................................................................................................. 5
3 Transport and storage .................................................................................................................................................................................................. 7
4 Setup and connection...................................................................................................................................................................................................8
4.1 Assembly................................................................................................................................................................................................................8
4.2 Electrical connections ........................................................................................................................................................................................8
4.3 Information on the correct operation of reed contacts in Bühler level switches.............................................................................8
5 Operation and control ................................................................................................................................................................................................ 10
5.1 Start-up procedure ...........................................................................................................................................................................................10
5.2 LED statuses ........................................................................................................................................................................................................ 10
5.3 General key functions ....................................................................................................................................................................................... 11
5.4 Keylock enabled .................................................................................................................................................................................................. 11
5.5 Menu overview .................................................................................................................................................................................................. 12
5.6 Changing basic settings ...................................................................................................................................................................................13
5.6.1 Disabling normal error handling................................................................................................................................................... 13
5.6.2 Define switching outputs ................................................................................................................................................................ 13
5.6.3 Set temperature unit.........................................................................................................................................................................14
5.6.4 Set display refresh rate .....................................................................................................................................................................14
5.6.5 Enable/disable keylock......................................................................................................................................................................14
5.6.6 Restore factory settings (Reset) ...................................................................................................................................................... 15
5.7 Switching outputs............................................................................................................................................................................................. 16
5.7.1 Switching output x: Definition of the switching characteristic...........................................................................................16
5.7.2 Switching output x: Upper switching limit (switching point).............................................................................................. 17
5.7.3 Switching output x: Lower switching limit (switch-back point) ..........................................................................................18
5.7.4 Switching output x: Switch-on delay ...........................................................................................................................................18
5.7.5 Switching output x: Switch-back delay .......................................................................................................................................18
5.7.6 Switching output x: Testing the switching output ..................................................................................................................19
5.7.7 Change status LED display function .............................................................................................................................................19
5.8 Analogue outputs ............................................................................................................................................................................................ 20
5.8.1 Analogue output x: Assigning the upper limit......................................................................................................................... 20
5.8.2 Analogue output x: Lower limit assignment .............................................................................................................................21
5.8.3 Analogue output x: Signal type assignment.............................................................................................................................. 21
5.8.4 Analogue output x: Testing the analogue output ................................................................................................................... 21
5.9 Diagnostic options ............................................................................................................................................................................................22
5.9.1 View logbook....................................................................................................................................................................................... 22
5.9.2 Maximum and minimum temperature ......................................................................................................................................23
5.9.3 Define switching output to log ......................................................................................................................................................23
5.9.4 Delay for storing the Min/Max Temperature ............................................................................................................................23
6 Cleaning and Maintenance.......................................................................................................................................................................................24
7 Service and repair......................................................................................................................................................................................................... 25
7.1 Troubleshooting ................................................................................................................................................................................................25
8 Disposal...........................................................................................................................................................................................................................26
9 Appendices..................................................................................................................................................................................................................... 27
9.1 Technical Data NT-ELD.....................................................................................................................................................................................27
9.2 NT-ELD temperature outputs ........................................................................................................................................................................28
9.3 NT-ELD standard pin assignment.................................................................................................................................................................28
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9.4 Current settings.................................................................................................................................................................................................29
9.5 Display ranges....................................................................................................................................................................................................29
9.6 Display resolution .............................................................................................................................................................................................29
9.7 Menu Sequence Overview ...............................................................................................................................................................................31
10 Attached documents...................................................................................................................................................................................................32
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1 Introduction
1.1 Intended Use
Level switches are used to monitor the liquid level and temperature in fluid systems.
Level switches must not be used in highly flammable or corrosive liquids.
The medium must not contain particles, particularly metallic particles, to prevent deposits on the float or between the float and
switching tube. If necessary, filter the medium.
Please note the technical data in the appendix for the specific intended use, existing material combinations, as well as temper-
ature limits.
WARNING
All device models are solely intended for industrial applications. They are not safety com-
ponents. The devices must not be used if failure or malfunction thereof jeopardises the
safety and health of persons.
Use in explosive areas is prohibited.
1.2 Functionality
1.2.1 Liquid level monitoring
The measuring tube is located inside the tank. The level switches are located inside the measuring tube. These are activated by a
magnet inside the level switch float.
The contacts are soldered to the board, spaced as specified in the purchase order.
1.2.2 Temperature monitor
Temperature is monitored via temperature sensor (Pt100) inside the sensor tube. Depending on the version, there are several
switching outputs combined with one analogue output (4 - 20mA). The temperature is shown in the display.
Please note the technical data in the appendix.
1.3 Ordering instructions NT-ELD
NT-ELD
G1/2
M20
UNF
Brass
MS
Version
Type designation
Connection
Plug
XX
LED temperature display
2T
2 x M12
Length
280
370
500
variable (please specify)
Number of level contacts
1K or 2K (NC / NO)
XX XX XX XX XX XX XX XX XX
Installation dimensions L1 = ...mm
1st level contact
Switching function 1st Contact
NO / NC
Installation dimensions L2 = ...mm
2nd level contact
Switching function 2nd contact
NO / NC
2 x temperature output
1T-KT
1 x temperature output
1 x analogue output
= G1/2
= M20x1.5
= 7/8-14 UNF
Ordering example
You require: Level switch with G1/2 connection, brass, length L= 500 mm, 2 level contacts,
1st contact 100 mm NC, 2nd contact 450 mm NO,
temperature analysis with display and 2 programmable outputs.
Order: NT-ELD-MS-G1/2-2M12/500-2K-100NC-450NO-2T
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1.4 Scope of Delivery
– Level switch
– Product documentation
– Connection/mounting accessories (optional)
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2 Safety instructions
2.1 Important advice
Operation of the device is only valid if:
– the product is used under the conditions described in the installation- and operation instruction, the intended application
according to the type plate and the intended use. In case of unauthorized modifications done by the user Bühler Technolo-
gies GmbH can not be held responsible for any damage,
– when complying with the specifications and markings on the nameplates.
– the performance limits given in the datasheets and in the installation- and operation instruction are obeyed,
– monitoring devices and safety devices are installed properly,
– service and repair is carried out by Bühler Technologies GmbH,
– only original spare parts are used.
This manual is part of the equipment. The manufacturer keeps the right to modify specifications without advanced notice. Keep
this manual for later use.
Signal words for warnings
DANGER
Signal word for an imminent danger with high risk, resulting in severe injuries or death if not avoided.
WARNING
Signal word for a hazardous situation with medium risk, possibly resulting in severe injuries or death if not
avoided.
CAUTION
Signal word for a hazardous situation with low risk, resulting in damaged to the device or the property or
minor or medium injuries if not avoided.
NOTICE
Signal word for important information to the product.
Warning signs
These instructions use the following warning signs:
Warns of a general hazard General information
Warns not to inhale toxic gasses Wear respiratory equipment
Warns of corrosive liquids Wear a safety mask
Warns of explosive areas Wear gloves
2.2 General hazard warnings
The equipment must be installed by a professional familiar with the safety requirements and risks.
Be sure to observe the safety regulations and generally applicable rules of technology relevant for the installation site. Prevent
malfunctions and avoid personal injuries and property damage.
The operator of the system must ensure:
– Safety notices and operating instructions are available and observed,
– The respective national accident prevention regulations are observed,
– The permissible data and operational conditions are maintained,
– Safety guards are used and mandatory maintenance is performed,
– Legal regulations are observed during disposal.
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Maintenance, Repair
Please note during maintenance and repairs:
– Repairs to the unit must be performed by Bühler authorised personnel.
– Only perform conversion-, maintenance or installation work described in these operating and installation instructions.
– Always use genuine spare parts.
Always observe the applicable safety and operating regulations in the respective country of use when performing any type of
maintenance.
The method for cleaning the devices must be adapted to the IP protection class of the devices. Do not use cleaners which could
damage the device materials.
DANGER Toxic, acidic gases/liquids
Protect yourself from toxic, corrosive gasses/liquids when performing any type of work.
Wear appropriate protective equipment.
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3 Transport and storage
Only transport the product inside the original packaging or a suitable alternative.
The equipment must be protected from moisture and heat when not in use. It must be stored in a covered, dry, dust-free room
at room temperature.
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4 Setup and connection
DANGER Toxic, acidic gases/liquids
Protect yourself from toxic, corrosive gasses/liquids when performing any type of work.
Wear appropriate protective equipment.
4.1 Assembly
Please note before installing the level switch!
After transport and delivery of the level switch, the switching status of the bistable contacts may be different than required for
proper operation.
Therefore slide the float for the level switch along the level switch tube from below immediately before installation.
This ensures all built-in bistable contacts have a clearly defined switching status (NC or NO).
The level switch comes fully assembled and can be mounted to the tank with 30 Nm of torque. Please be sure the float can move
freely and to leave enough space between the tank wall and add-ons.
After removing the float, where applicable, be sure the magnet inside the float is above the fluid level. This can easily be verified
with a piece of iron to determine the magnet position inside the float.
The level contacts are mounted (with the tank empty) as NO contact (NO) or NC contact (NC).
The contact logic assumes the level switch is installed in an empty tank, i.e. it is only in the operating position once filled.
4.2 Electrical connections
The level switch is powered by 24V (max. 30V). The switch connects with a cable and standard M12 plug-in connectors. Please
refer to the appendix for installation dimensions and plug configuration.
4.3 Information on the correct operation of reed contacts in Bühler level switches
Based on their construction, reed contacts are very long lasting and reliable components. Yet the following should be considered
when using them:
Life of reed switches
The life of reed switches can be up to 109 cycles. This is reduces by high stress and / or incorrect or the absence of protective cir-
cuits when switching inductive, capacitive or lamp loads.
It’s therefore important to ensure NEVER to exceed one or several of the maximum approved limits, even temporarily, and to
install a contact protective circuit for loads which are not purely ohmic. Using test lamps when installing the devices is also pro-
hibited, as these can temporarily allow too much current to flow, which can damage the reed contacts. In this case non-volatile
testing equipment should always be used.
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Contact protective circuits for reed switches
For direct current voltage a recovery diode per figure A must be connected parallel to the contact.
For alternating current voltage an RC circuit per Figure B and Table 1 must be connected parallel to the contact.
A B
Load
Contact
Recovery diode
Load
Contact
RC circuit
Load in VA 10 25 50
Voltage at contact V R/Ohm C/µF R/Ohm C/µF R/Ohm C/µF
24 22 0.022 1 0.1 1 0.47
60 120 0.0047 22 0.022 1 0.1
110 470 0.001 120 0.0047 22 0.022
230 470 0.001 470 0.001 120 0.0047
Please note the max. voltage/load ratings of the respective level contacts!
Voltages and currents
All Bühler level contacts with reed switch can switch minimal Switching voltages of 10 µV and minimal switching currents of 1
µA.
The maximum values specified for the respective contact types apply.
Level contact with reed switches can therefore be used for SPS applications as well as for high loads (within the maximum lim-
its) without hesitation.
Contact material
All reed switches in Bühler level contacts use rhodium as the contact material for the actual contact areas.
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5 Operation and control
NOTICE
The device must not be operated beyond its specifications.
5.1 Start-up procedure
The device will automatically switch on when connected to power. It will first briefly display the software version, at which time
the device will also check the built-in components. The display will then switch to displaying measurements.
The following describes the function of the display and control unit:
LEDs
Control keys
Display
If an error message appears in the display during operation, please refer to the Troubleshooting table under chapter “Service
and Repair”.
5.2 LED statuses
LEDs above the measurement display indicate the status of the temperature switching outputs. The LEDs are permanently as-
signed to the switching outputs.
The following table shows the factory settings:
LED 1 – yellow
Status temperature switching output 1
LED 2 - red
Status temperature switching output 2
The switching characteristics of the LED (on if switching contact closed or open) can be changed.
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5.3 General key functions
The keys below the display are used for operation.
The menu controls are detailed in the following chapters.
Key Mode Function
– Measurement display: Change measured variables displayed.
– In the menu: Move down one menu level.
Move up one menu level.
– At the end of the menu:
The display indicates the end of the menu.
– Following input/selection: Confirm and save a numerical value entered or a function selection. The dis-
play will flash if a parameter has been changed.
– Measurement display: Displays the configuration.
– In the menu: Scroll up menu item, numerical value or function selection. Holding the key
will continuously scroll.
– Measurement display: Go to main menu.
– In the menu: Scroll down menu item, numerical value or function selection. Holding the key
will continuously scroll.
+ – In the menu: Exit the main / sub / drop-down menu and return to displaying the measure-
ment without saving changes to the parameters.
+ – In the menu: Move to the next higher menu level.
60 s no action – In the menu: Exit the main / sub/ drop-down menu.
To select a menu item and to enter values:
– Open the main menu with the key.
– Select the submenu with the and keys and open the submenu with the key.
– If necessary, select the next submenu with the and keys and open with the key.
– Select the desired menu item with the and keys and open the list of values with the key.
– Set the value with the and keys and confirm with the key. The new settings will the saved and the device will return
to the submenu.
– Select the menu item EXIT to exit the submenu and confirm with the key. The device will return to the next menu level up
or to the measurement display.
5.4 Keylock enabled
With the keylock enabled, selecting the menu with the key will display in place of the main menu. The active
digit will be indicated by a dot.
– Use the and keys to enter the code and confirm with the key. The active digit will move one place to the right. After
entering the 3rd digit the main menu will open.
If the wrong code is entered, the device will return to the measurement display. If you forgot the password you can always enter
master code 287 to access the menu.
You can cancel the keylock under Loc in submenu Basic Settings Advanced Options b.EF and enter 000 to reset the code.
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5.5 Menu overview
The menu structure is based on the VDMA standard sheet 24574-1. The menu structure is hierarchic. The top menu level contains
the main menu items, e.g. tEMP, b.EF, diA, E. Each main menu has additional submenu items.
The menu items may vary depending on the device configuration. Not all menu items described below will necessarily apply to
your device. Press the key in display mode to open the configuration. A 4-digit code will appear, e.g.
With the 4 digits tsav meaning:
t: Model
s: Number of switching outputs
a: Number of analogue outputs
v: Device installation type
t = temperature measurement
2
0
i = standard installation (tank installation)
Configuration
Equipment configuration
t___
____
tEMP
Display
Measurement display
Temperature
Temperature main menu
out1
Settings menu OUT1
Out 1
out_
Settings menu OUTX
Out X
An 1
Settings menu Analog 1
Analog Out 1
E
Exit menu level
Exit
b.EF
Basic Adv. Functions
Basic EF
If applicable
If applicable
DiA
Diagnostics menu
Diagnostic
E
Exit menu level
Exit
____ ____
Toggle display
Toggle
The individual menu items will not be shown if the option does not apply. Example: With a=0 the menu items for configuring
the analogue output does not apply. You can then skip the description for this item.
The switching outputs can be configured in the Temperature (tEMP) main menu.
The basic device settings can be changed. General settings can be configured under Basic Settings Advanced Functions (b.EF).
These settings should be configured first, as they affect the displays and settings for the individual menus. These settings are
e.g. the units used and allocating switching outputs for measuring the temperature.
The Diagnostic (dia) menu further contains diagnostics options.
For the detailed illustration of the entire menu structure please refer to the original operating instructions at the end of this
chapter.
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5.6 Changing basic settings
The general basic settings can be changed under menu Basic Settings Extended Functions (bEF). These settings will affect the
measurement display and the configuration options in the various main menus. Here you can also change the switching output
assignment.
– Press the key to open the main menu.
– Select menu item (EF) using the and keys and open the menu with the key.
NOTICE Disabling normal error handling
Disabling normal error handling and analysis could potentially cause dangerous operat-
ing states, dangers to the user or machines. Before using this option, review the hazard
potential within the process. With this setting, Bühler Technologies GmbH assumes no li-
ability for injuries to health or material damage caused by this setting.
5.6.1 Disabling normal error handling
Here you can enable/disable normal error handling and analysis
The function Disable error handling (Err.h) is used to disable normal error handling and analysis. This may pose dangers to the
user or machine.
Basic EF b.EF
Basic ext. functions
Err.h
Disable error handling
Set error handling ___
no - YES
Confirm
The options are:
Disables normal error handling. Enables normal error handling (default)
Important note: When exceeding the measuring range or if sensor errors occur, the measurement
will be frozen and all six LEDs in the status bar will blink. When the measurement returns to the
permissible range the LEDs will stop blinking and the display will refresh again as usual.
5.6.2 Define switching outputs
Here you can define the switching outputs.
Use the “Define switching outputs” function to define the switching outputs (r.ou1 and r.ou2). The switching outputs can be
configured as Err, oil and tEMP .
Basic EF b.EF
Basic Adv. Functions
r.ou1/2
Define switching outputs
SET Output ____
Err - oil - tEMP
Selection menu
Options:
[Err, oil, tEMP]
The options are:
Err oil TEMP
Note:
– Switching outputs 1 and 2 can alternatively be wired as error indicators. In this case the output
will be connected as a NC contact which opens when exceeding the range or if an error occurs.
The LED assigned to this output will generally not be activated, as all 6 LED's in the status bar
will blink if an error occurs.
– When defining a switching output as an error indicator it will no longer be an option for normal
switching output settings.
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5.6.3 Set temperature unit
This is where the unit symbol for the temperature is configured:
Basic EF b.EF
Basic Adv. Functions
t.uni
Temperature unit
Set Unit Temp ;_
;C - ;F
Selection menu
The options are:
Degrees
Celsius
Degrees
Fahrenheit
Note:
– Values are automatically converted and the measuring range adjusted. However, always check
the respective switching points and switch-back points.
5.6.4 Set display refresh rate
The refresh rate of the display can be changed based on the application. The display can also be completely disabled. The LEDs
will remain functional.
Basic EF b.EF
Basic Adv. Functions
Di5
Display rate
Display Rate ____
FASt - oFF
Selection menu
The options are:
fast medium slow Display off
Note:
– Error messages will still appear, even with the display off.
5.6.5 Enable/disable keylock
The keylock can be enabled to prevent unauthorised changes to the device settings.
Basic EF b.EF
Basic Adv. Functions
Lock
Locks the keys
Lock Device ___
0 - 999
Selection menu
The keylock will be enabled after entering at least one digit > 0. A dot indicates the active digit during this input.
Setting range:
000 to 999
– Use the key to open the list of values:
– Enter the digit using the and keys (0 to 9) and press the key to confirm. The active digit
will move one place to the right.
– Lastly, press the key to confirm the code.
The device will now return to the submenu.
Note:
– To disable the keylock enter: 000
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5.6.6 Restore factory settings (Reset)
Use the Reset function (rES) to restore the factory settings. All changes will be lost. Since this will also reset the limits, you must
check the temperature settings.
Basic EF b.EF
Basic Adv. Functions
rES
Factory setting
Reset ___
no - YES
Confirm
The options are:
Original status:
No,
keep current settings
Original status:
Yes,
reset settings to the factory defaults.
The factory settings are:
Definitions:
SP x / rPxSwitching point / switch-back point x
ds x / drxSwitch-on delay / switch-back delay for switching output x
A x ..Hi / Ax.Lo Maximum and minimum measurement for output*
A.ou xAnalogue output signal type*
ou xSwitching characteristic for switching output x
t.uni Temperature unit
dis Display refresh rate
Loc Keylock
SJ.ou Switching output logged
dt.MM Delay for recording the minimum / maximum temperature
Note: For customer-specific specifications the factory preset may vary from those listed here.
*analogue output only.
Version with 2 switching outputs:
Switching outputs Basic Settings
SP1 / rP1 50 / 45 t.uni °C
ds1 / dr1 / ou1 0 / 0 / Hno dis FASt
SP2 / rP2 60 / 55°C Loc 000
ds2 / dr2 / ou2 0 / 0 / Hno
Version with 1 switching output and 1 analogue output:
Switching outputs Basic Settings
SP1 / rP1 50 / 45 t.uni °C
ds1 / dr1 / ou1 0 / 0 / Hno r.ou1 tEMP
Analogue output dis FASt
A1.Hi / A1.Lo / A.ou1 0 / 100 / i1 Loc 000
Diagnostic settings:
Diagnostics
SJ.ou out1
dt.MM 0.0
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5.7 Switching outputs
All switching outputs are configured the same way. The switching output number is therefore represented by x. Open the
switching output to be configured from the menu for the respective measured variable.
Display ____
Measurement display
____
Measured variable main menu
Measured variable out_
Out X
Settings menu OUTX
The switching output allocation and other basic settings related to all switching outputs can be configured in menu Basic Set-
tings Advanced Functions.
Use submenu Advanced Functions to configure additional settings for each individual switching output which e.g. affect the
switching characteristics of the output. The output can also be tested here.
5.7.1 Switching output x: Definition of the switching characteristic
The switching characteristic for the output can be configured under the following menu:
Measured variable ____ out_
Measured variable main menu
Out X EF_
EF X
Advanced Functions
ou_
Set Out X
Definition OUTX
___
Selection menu
Hno - FM
Settings menu OUTX
The options are:
Hysteresis Function
Hysteresis function
as the NO contact
Hysteresis function
as the NC contact
NO contact or NC contact function when the
output signal is set when exceeding the con-
figured switching point. The output signal
will be deleted if the value is below the con-
figured switch-back point.
Here, NO contact (Hno) means the PNP
switching output is closed above switching
point SPx and opens below switching point
rPx.
Here, NC contact (Hnc) means the PNP switch-
ing output is open above switching point SPx
and closes below switching point rPx.
Also see the explanation in the drawing be-
low.
SP
rP
Hno
(NO contact)
Hnc
(NC contact)
Hysteresis
SP-rP
()
Time t
Time t
Time t
Window function
Window function
as NO contact
Window function
as NC contact
NO contact or NC contact function defining a
signal window. When the measuring window
is reached the output signal is set and de-
leted upon exiting.
Here, NO contact (Fno) means the PNP
switching output is closed if the value is
within the window. Otherwise the switching
output will be open.
Here, NC contact (Fnc) means the PNP switch-
ing output is open if the value is within the
window. Otherwise the switching output will
be closed.
FH
FL
Fno
(NO contact)
Fnc
(NC contact)
Time t
Time t
Time t
Window
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Frequency output
Frequency output
If the output is defined as a frequency out-
put, a square wave signal with a frequency
between 1Hz and 100Hz proportional to the
measurement will be output.
Note: To increase the slew rate of the square
wave signal, we recommend loading the
switching output with an load of 10kΩ.
T ≤
corresponds
to f = 1 Hz
Time t
Time t
Time t
T = 47.5 °C
corresponds
to f = 50 Hz
T ≥
corresponds
to f = 100 Hz
F ILo F IHi
Example: = 15 °C, = 80 °C
with temperature T and frequency f:
F ILo
F IHi
open
(0)
closed
(1)
open
(0)
closed
(1)
rising NO contact
falling NC contact
NO (normally open)
rising NC contact
falling NO contact
NC (normally closed)
Hno Hnc
Note: The designation of the switching function may vary:
Measured variable
5.7.2 Switching output x: Upper switching limit (switching point)
The upper switching limit for switching output Out x can be defined with the following submenu:
Measured variable tEMP out_
Measured variable main menu
Out X ____
SPI FHI F I.Hi
Switching point X
____
Selection menu
0 °C - 100 °C
Settings menu OUTX
Setting range:
0 °C to 100 °C
(32 °F to 212 °F)
Switching point for OUT x
Note:
– The switching point must be set to within the range limits (see menu Basic Settings Advanced
Functions).
– If switching output OUT x was assigned the function Window, will appear. The
setting corresponds with the upper window limit.
– If switching output OUT x was assigned the function Frequency output, will ap-
pear. The setting corresponds to the frequency 100 Hz.
17Bühler Technologies GmbHBE100026 ◦ 08/2017

Nivotemp NT-ELD
5.7.3 Switching output x: Lower switching limit (switch-back point)
The lower switching limit for switching output Out 1 can be defined in the following submenu:
Measured variable tEMP out_
Measured variable main menu
Out X ____
rPI FLI F I.Lo
Switch-back point X
____
Selection menu
0 °C - 100 °C
Settings menu OUTX
Setting range:
0 °C to 100 °C
(32 °F to 212 °F)
Switch-back point for OUT x
Note:
– The switch-back point must be set to within the range limits and must always be lower than the
switching point.
– If switching output OUT x was assigned the function Window, will appear. The
setting corresponds with the lower window limit.
– If switching output OUT x was assigned the function Frequency output, will ap-
pear. The setting corresponds to the frequency 1Hz.
5.7.4 Switching output x: Switch-on delay
The menu Advanced Functions EFx is used to configure additional settings for switching output x. The submenu is at the second
submenu level.
The switching and switch-back delay prevents the alarm being triggered too frequently in unstable conditions. The switching
delay can be configured with the following menu:
Measured variable ____ out_
Measured variable main menu
Out X EF_
EF X
Advanced Functions
dS_
Delay SP X
Delay OUTX On
___
Selection menu
0 - 100
Settings menu OUTX
Setting range:
0…100 seconds
Time span in seconds during which the signal must be continuously present for the switching out-
put to respond.
Note:
– If switching output OUTx was assigned the function Window, the setting corresponds to the
switch-on delay which detects valid reaching of the measuring window.
– If switching output OUT x was assigned the function Frequency output, this value will have no
affect.
5.7.5 Switching output x: Switch-back delay
The switch-back delay can be configured with the following menu:
Measured variable ____ out_
Measured variable main menu
Out X EF_
EF X
Advanced Functions
dr_
Delay RP X
Delay OUTX Off
___
Selection menu
0 - 100
Settings menu OUTX
Setting range:
0…100 seconds
Switch-back signal delay for OUT x.
Time span in seconds during which the signal must be continuously present for the switching out-
put to respond.
Note:
– If switching output OUTx was assigned the function Window, the setting corresponds to the
switch-on delay which detects valid closing of the measuring window.
– If switching output OUTx was assigned the function Frequency output, this value will have no
affect.
18 Bühler Technologies GmbH BE100026 ◦ 08/2017