Bühler technologies Nivotemp NT 61 User manual

Fluidcontrol
Installation and Operation Instructions
Original instructions
Level- and temperature switch
Nivotemp NT 61, NT 61-HT, NT 63, NT 63-LTD/Nivovent NV 71, NV 73
BE100019
08/2020
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 2020
Document information
Document No.......................................................... BE100019
Version........................................................................ 08/2020

Nivotemp NT 61, NT 61-HT, NT 63, NT 63-
LTD/Nivovent NV 71, NV 73
Contents
1 Introduction..................................................................................................................................................................................................................... 2
1.1 Intended Use.........................................................................................................................................................................................................2
1.2 Functionality......................................................................................................................................................................................................... 2
1.2.1 Liquid level monitoring ......................................................................................................................................................................2
1.2.2 Temperature monitor .........................................................................................................................................................................2
1.3 Design types.......................................................................................................................................................................................................... 3
1.4 Model key NT61 .................................................................................................................................................................................................... 3
1.5 Model key NT61-HT..............................................................................................................................................................................................4
1.6 Model key NT63....................................................................................................................................................................................................4
1.7 Model key NV71 .................................................................................................................................................................................................... 5
1.8 Model key NV73.................................................................................................................................................................................................... 5
1.9 Scope of Delivery..................................................................................................................................................................................................6
2 Safety instructions......................................................................................................................................................................................................... 7
2.1 Important advice................................................................................................................................................................................................. 7
2.2 General hazard warnings .................................................................................................................................................................................8
3 Transport and storage ..................................................................................................................................................................................................9
4 Setup and connection................................................................................................................................................................................................. 10
4.1 Installation ..........................................................................................................................................................................................................10
4.2 Information on the correct operation of reed contacts in Bühler level switches............................................................................ 11
4.3 Adjusting level contacts (NT61, NV71 only)................................................................................................................................................. 12
4.4 Settings..................................................................................................................................................................................................................13
5 Operation and control ................................................................................................................................................................................................ 14
6 Cleaning and Maintenance........................................................................................................................................................................................15
6.1 Replacing the filter element............................................................................................................................................................................15
6.2 Adding small amounts of oil...........................................................................................................................................................................15
7 Service and repair......................................................................................................................................................................................................... 16
7.1 Spare parts and accessories ........................................................................................................................................................................... 16
8 Disposal............................................................................................................................................................................................................................17
9 Appendices..................................................................................................................................................................................................................... 18
9.1 Technical Data NT 61......................................................................................................................................................................................... 18
9.2 Technical Data NT 61-HT.................................................................................................................................................................................. 19
9.3 Technical Data NT 63....................................................................................................................................................................................... 20
9.4 Technical Data NV 71......................................................................................................................................................................................... 21
9.5 Technical Data NV 73 ........................................................................................................................................................................................22
9.6 Dimensions NV 71..............................................................................................................................................................................................23
9.7 Dimensions NV 73..............................................................................................................................................................................................24
9.8 Standard pin assignment NT 61, NT 61-HT.................................................................................................................................................25
9.9 Standard pin assignment NV 71....................................................................................................................................................................27
9.10 Standard pin assignment NT 63, NV 73.......................................................................................................................................................29
9.11 Standard pin assignment NT 63-LTD...........................................................................................................................................................30
9.12 Standard pin assignment NV 73 ....................................................................................................................................................................31
9.13 Definitions...........................................................................................................................................................................................................32
10 Attached documents................................................................................................................................................................................................... 33
iBühler Technologies GmbHBE100019 ◦ 08/2020

Nivotemp NT 61, NT 61-HT, NT 63, NT 63-
LTD/Nivovent NV 71, NV 73
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.
On models NT63 and NV73 the liquid level is continuously measured via reed-contact. The data is output via 4-20mA analogue
signal. The NT63-LTD has an IO-Link standard interface for output.
On models NT61 and NV71 the contacts are mounted to a perforated rail spaced as specified in the purchase order, but can be
moved if necessary.
1.2.2 Temperature monitor
The temperature is monitored via thermal element mounted to the end of the rail. Choose from temperature contacts with
fixed increments, a resistance thermometer (Pt100) or a temperature transmitter.
In the case of continuous temperature measurement (model key "KT" / temperature transmitter) an analogue signal between 4
and 20mA is output. The NT 63-LTD only has an IO-Link standard interface for output.
When equipped with resistance thermometer (model key "Pt100") the temperature is output using the change in resistance
(0°C = 100Ω) of the Pt100.
Please note the technical data in the appendix.
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LTD/Nivovent NV 71, NV 73
1.3 Design types
The level switch is equipped with different switching and analogue outputs based on the configuration. The outputs are freely
programmable.
The Nivovent type can be equipped with the following options:
VS Optical contamination indicator for the vent filter: analogue negative pressure display, display range 0.35 bar (5.1 PSI).
BFA* Filling adapter incl. ribbed flange with screen insert: This option enables adding small amounts of oil through the vent
filter housing. The selected version is built into the respective housing for this purpose.
SSR* Stilling tube with centring disc and filling adapter: Just as with the BFA, this contains both the stilling tube option as
well as the filler. The stilling tube is made from the same material as the selected immersion tube (MS/VA).
MT for installation into the multiterminal: Here the basic version is built into the multiterminal (MT).
MTS for installation into the multiterminal including stilling tube: In addition to the basic version, a stilling tube with cent-
ring disc is built into the multiterminal.
FCT Fluidcontrolterminal: Here the fluid control terminal (FCT) is mounted directly onto the basic version.
* not in conjunction with FCT and MT/MTS option
The SSR option is available for the Nivotemp type.
Please refer to the type plate for your equipment configuration. In addition to the job number, this also contains the item num-
ber and type designation.
1.4 Model key NT61
Model designation
Version
MS
VA
Brass
float and immersion tube
Plug connector
M3
S6
M12
2M12
C6F
Length in mm (max. 1500)
280
370
500
nn
Standard lengths
variable, please specify value
Level measurement
1-4 Number of contacts
K
W
Model K10 (NC/NO)
Model W11 (change-over contact)
1st temperature signal
TK...
NC contact NO contact
TK50NC
TK60NC
TK70NC
TK80NC
TK50NO
TK60NO
TK70NO
TK80NO
= 50 °C
= 60 °C
= 70 °C
= 80 °C
TM...
TM50NC
TM60NC
TM70NC
TM80NC
TM50NC
TM60NC
TM70NC
TM80NC
TM50NO
TM60NO
TM70NO
TM80NO
= 50 °C
= 60 °C
= 70 °C
= 80 °C
Pt100
KT
Temperature sensor
Temperature transmitter
TM... TM50NO
TM60NO
TM70NO
TM80NO
= 50 °C
= 60 °C
= 70 °C
= 80 °C
2nd temperature contacts (TM... only)
NO contactNC contact
Stilling tube
SSR
Cannot be combined with temperature contact
1)
NT 61
Level contact
Options
1)
1) 2)
2) With KT only 10 - 30 V DC
------------
------------
------------
------------
------------ ------------ -nn
-nn
3) For version with 2 temperature contacts
3)
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LTD/Nivovent NV 71, NV 73
1.5 Model key NT61-HT
Model designation
Version
HT
Stainless steel
Plug connector
M3
S6
M12
2M12
C6F
Length in mm (max. 1500)
280
370
500
nnn
Standard lengths
variable, please specify value
Level measurement
1-4 Number of contacts
K
K-HT
W
W-HT
Model K10 (NC/NO)
Model K10HT (NC/NO)
Model W11 (change-over contact)
Model W11HT (change-over contact)
1st temperature signal
TK...
NC contact NO contact
TK50NC
TK60NC
TK70NC
TK80NC
TK50NO
TK60NO
TK70NO
TK80NO
= 50 °C
= 60 °C
= 70 °C
= 80 °C
TM... TM50NC
TM60NC
TM70NC
TM80NC
TM50NO
TM60NO
TM70NO
TM80NO
= 50 °C
= 60 °C
= 70 °C
= 80 °C
Pt100
KT
Temperature sensor
Temperature transmitter
TM... TM50NC
TM60NC
TM70NC
TM80NC
TM50NO
TM60NO
TM70NO
TM80NO
= 50 °C
= 60 °C
= 70 °C
= 80 °C
2nd temperature contacts (TM... only)
NO contactNC contact
Stilling tube
SSR
Cannot be combined with temperature contact
Not adjustable
3)
2)
4) With KT only 10 - 30 V DC
NT 61
Level contact
Options
2)
2)
3)
3) 4)
1)
Please specify position and switching function per model key
Example: L1 = nnn mm NC
1)
------------------------
------------
------------
-nn
-nn
------------
------------
For version with two temperature contacts
5)
5)
1.6 Model key NT63
NT 63
M3
M12
Brass
float and VA immersion tube
MS
VA
Version
280
370
500
670
820
970
1120
1270
1420
Optional
SSR
Stilling tube
Model designation
Plug connection
Length (max. 1420 mm)
Measuring mode
K
KN
LTD
Level and temperature measurement
only level measurement
Level and temperature measurement (IO-Link)
---- ---- ---- ---- ----
(only K/KN)
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Nivotemp NT 61, NT 61-HT, NT 63, NT 63-
LTD/Nivovent NV 71, NV 73
1.7 Model key NV71
Type designation,
HY filter
Version
MS
VA
Brass
float / VA immersion tube
Plug connector
M3
S6
M12
2M12
Length in mm (max. 1500)
280
370
500
nnn
Standard lengths
variable, please specify value
Level measurement
1-4 Number of contacts
K
W
Model K10 (NC/NO)
Model W11 (change-over contact)
1st temperature signal
TK...
NC contact NO contact
TK50NC
TK60NC
TK70NC
TK80NC
TK50NO
TK60NO
TK70NO
TK80NO
= 50 °C
= 60 °C
= 70 °C
= 80 °C
TM... TM50NC
TM60NC
TM70NC
TM80NC
TM50NO
TM60NO
TM70NO
TM80NO
= 50 °C
= 60 °C
= 70 °C
= 80 °C
Pt100
KT
Temperature sensor
Temperature transmitter
TM... TM50NC
TM60NC
TM70NC
TM80NC
TM50NO
TM60NO
TM70NO
TM80NO
= 50 °C
= 60 °C
= 70 °C
= 80 °C
2nd temperature contact (TM... only)
NO contactNC contact
Contamination indicator
Filling adapter
Stilling tube incl.
filling adapter
for multiterminal
for multiterminal with
stilling tube option
for Fluidcontrolterminal
VS
BFA
SSR
MT
MTS
FCT
Not in conjunction with option FCT
Please specify position and switching function per
model key, Example: L1 = nnn mm NC
not in conjunction with FCT, MT or MTS option
Cannot be combined with temperature contact
With KT only 10 - 30 V DC
For version with two temperature contacts
1)
NV 71-HY Options
Level contacts
2)
3)
4)
1)
2)
3)
3)
4)
4) 5)
5)
------------ ------------ -nn-nn------------ ------------ ------------ ------------ ------------
6)
6)
1.8 Model key NV73
NV 73-HY-
M3
M12
Brass
float and VA immersion tube
MS
VA
Version
280
370
500
670
820
970
1120
1270
1420
Options
VS Contamination indicator
BFA
SSR
FCT
MT
MTS
Filling adapter
Stilling tube with
filling adapter
Fluidcontrolterminal
for multiterminal
for multitermminal incl.
stilling tube
Not in conjunction with FCT option
Not in conjunction with FCT, MT or MTS option
Type designation, HY filter
Plug connection Length (max. 1420 mm)
Measuring mode
K
KN
Level and temperature measurement
Level measurement only
1)
1)
2)
2)
2)
-- - - -
5Bühler Technologies GmbHBE100019 ◦ 08/2020

Nivotemp NT 61, NT 61-HT, NT 63, NT 63-
LTD/Nivovent NV 71, NV 73
1.9 Scope of Delivery
– Level switch
– Product documentation
– Connection/mounting accessories (optional)
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Nivotemp NT 61, NT 61-HT, NT 63, NT 63-
LTD/Nivovent NV 71, NV 73
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 Unplug from mains
Voltage warning Wear respiratory equipment
Warns not to inhale toxic gasses Wear a safety mask
Warns of corrosive liquids Wear gloves
General information
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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,
– compliance with national installation regulations.
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.
– Do not install damaged or defective spare part. If necessary, visually inspect prior to installation to determine any obvious
damage to the 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.
9Bühler Technologies GmbHBE100019 ◦ 08/2020

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4 Setup and connection
DANGER Electric voltage
Risk of electric shock
a) De-energise the system.
b) The equipment may only be installed, maintained and put into operation by instruc-
ted, competent personnel.
c) Always observe the applicable safety regulations for the operating site.
DANGER Toxic, acidic gases/liquids
Protect yourself from toxic, corrosive gasses/liquids when performing any type of work.
Wear appropriate protective equipment.
4.1 Installation
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).
For direct installation to the tank, insert the switching tube into the designated bore (per DIN 24557, Part 2) with rubberised cork
seal on the tank. It secures to the flange using the included screws and seals. 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.
DANGER Electric voltage
Risk of electric shock
When connecting devices, please note the maximum voltages and currents currents (see
technical data) and use the correct wire cross-sections and circuit breakers.
When selecting the connection lines, also note the maximum operating temperatures of
the devices.
Installation in special areas of application:
If the device will be installed outdoors or in wet areas, the maximum operating voltage
is max. 16 V DC effective or 35 V DC.
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4.2 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.
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.
Magnetic fields
Avoid external magnetic fields, including from electric motors. These can interfere with the function of the reed switches.
Mechanical loads
Do not expose the level switch to strong blows or bending.
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4.3 Adjusting level contacts (NT61, NV71 only)
The level measurement contacts are mounted on a perforated rail inside the protective tube. These are arranged per order spe-
cifications but can be moved if necessary.
Depending on the model, the perforated rail will also have electronic assemblies. These are positioned so they do not limit the
setting range of the level contacts. Please be sure not to damage the assemblies during installation or removal. Models with the
designation K, KN or LTD supply a continuous 4-20mA signal. These devices do not require configuration.
For devices with 230 V mains voltage:
DANGER Electrical voltage
Electrocution hazard.
a) Disconnect the device from power supply.
b) Make sure that the equipment cannot be reconnected to mains unintentionally.
c) The device must be opened by trained staff only.
d) Regard correct mains voltage.
– Disconnect the voltage supply.
– Disconnect the plug.
–Models NT61: Unscrew the plug base. For plug-in connectors with screw-in plug base, unscrew the top hexagon ring and pull
the complete pin insert up until the bottom of the base can be unscrewed freely.
–Models NV71: Remove filter cover and element. Unscrew and remove the filter case. Unscrew the flange cover from the level
switch.
– Carefully pull the perforated rail with contacts out the top.
NOTICE
On versions with earth wire, this is run as a loop and soldered to the protective tube
from the inside in the insertion direction. To prevent breaking off the earth wire it
should not be pulled all the way out.
– Mark the original contact position.
– Lock the contacts in place in the desired positions. Please note the minimum spacing!
If the contacts are configured as NO contact (NO) or NC contact (NC), the contact function can be reversed by turning the con-
tacts 180°. The housing has symbols for NC contact and NO contact as well as an arrow. The arrow, which points up when in-
stalled, indicates the current contact function. The contact logic assumes the level switch is installed in an empty tank, i.e. it is
only in the operating position once filled.
Function NO contact (NO)
with rising level
Function NC contact (NC)
with rising level
– If the earth wire was pulled out of the protective tube, first insert this wire into the protective tube.
– Make a loop of the additional cable length and carefully slide the perforated rail in again.
–Models NT61: Screw on the plug base. For plugs with screw-in thread, attach the plug base clean and screw in hand tight.
Leave the pin insert free so the base can turn around the cables. Now slide the cables all the way in, lock the pin insert into
the guide and slide all the way in. Tighten the top hexagon ring hand tight.
–Models NV71: Screw on the flange cover. Screw on the filter case. Attach the filter cover and element.
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NOTICE
Ensure the seals are positioned correctly. Replace defective seals immediately!
4.4 Settings
All models in the series named "63-K..." continuously capture the liquid level and the temperature via reed-contact or a Pt100.
Sensor versions “63-K… and 63-KN…” output 4–20mA analogue signals (normally: 4mA lowest point, 20mA highest point).
These devices require no configuration.
Sensor versions “63-LTD” are available with digital interface.
Here the sensor uses the standardised technology IO-Link, an efficient point-to-point communication. It uses the previous,
proven and tested connection technology.
Compatibility with the previous technology is guaranteed. If no IO-Link master is connected, the outputs can be used as regular
switching outputs (1PNP liquid level output, 1PNP temperature output).
This allows configuring the switching points via the IO-Link interface.
For the respective IODD configuration data, please visit https://ioddfinder.io-link.com.
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5 Operation and control
NOTICE
The device must not be operated beyond its specifications.
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LTD/Nivovent NV 71, NV 73
6 Cleaning and Maintenance
This device is maintenance-free.
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.
For versions with filter:
The filter element must be replaced as needed, at least 1x annually. In exceptional cases a small amount of oil can be added via
the filter.
During maintenance, remember:
– The equipment must be maintained by a professional familiar with the safety requirements and risks.
– Only perform maintenance work described in these operating and installation instructions.
– When performing maintenance of any type, observe the respective safety and operation regulations.
6.1 Replacing the filter element
Replace the filter element as follows:
– Temporarily shut down the system.
– The filter cover counter-clockwise to open.
– Remove the filter element and dispose according to legal regulations.
– Insert the new filter element. Be sure to use the correct filter fineness!
– Screw on the filter cover.
– For filters with optical contamination indicator: Set the display to zero.
Hydac filter
When the maximum display value is reached, the red indicator piston will lock in place, indicating the filter service is required.
Press the yellow Reset button to reset the display to zero.
Button for resetting the indicator
Filtration Group filter
Filter contamination is indicated in percent (50%, 75% and 100 %). To reset the display to zero, turn the knob in the direction of
the arrow until the red part of the indicator disc is turned all the way back.
Knob for resetting the indicator
6.2 Adding small amounts of oil
Nivovent type with BFA or SSR option only:
– Temporarily shut down the system.
– The filter cover counter-clockwise to open.
– Remove the filter element.
– Slowly add oil through the nodular holes.
– Reinsert the filter element and close the cover.
– Restart the system.
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7 Service and repair
This chapter contains information on troubleshooting and correction should an error occur during operation.
Repairs to the unit must be performed by Bühler authorised personnel.
Please contact our Service Department with any questions:
Tel.: [phone] or your agent
If the equipment is not functioning properly after correcting any malfunctions and switching on the power, it must be inspected
by the manufacturer. Please send the equipment inside suitable packaging to:
Bühler Technologies GmbH
- Reparatur/Service -
Harkortstraße 29
40880 Ratingen
Germany
Please also attach the completed and signed RMA decontamination statement to the packaging. We will otherwise be unable to
process your repair order.
You will find the form in the appendix of these instructions, or simply request it by e-mail:
[email protected].
7.1 Spare parts and accessories
Accessories
Item no. Description
9144 05 0010 Connecting cable M12x1, 4-pin, 1.5 m, angular coupling and straight plug
9144 05 0046 Connecting cable M12x1, 4-pin, 3.0 m, angular coupling and straight plug
9144 05 0047 Connecting cable M12x1, 4-pin, 5.0 m, angular coupling and strands
16 Bühler Technologies GmbH BE100019 ◦ 08/2020

Nivotemp NT 61, NT 61-HT, NT 63, NT 63-
LTD/Nivovent NV 71, NV 73
8 Disposal
Dispose of parts so as not to endanger the health or environment. Follow the laws in the country of use for disposing of elec-
tronic components and devices during disposal.
17Bühler Technologies GmbHBE100019 ◦ 08/2020

Nivotemp NT 61, NT 61-HT, NT 63, NT 63-
LTD/Nivovent NV 71, NV 73
9 Appendices
9.1 Technical Data NT 61
Basic Unit
Version MS VA
Ø50 (MS)
Ø60.3 (VA)
65
L
L2 = min. 70
L1 = min. 30
with VA stilling tube
3.5
min. 40*
last contact
1st contact
4 8
*min 80 with temperature
Ø44
Rubberised cork seal
Stilling tube optional
min. Ø60
min. 55*
last contact
Ø51
3.5 57
* min. 80 with temperature
Ø60*
6x Ø6
Ø73
Ø90
*min. Ø61 for VA version with
stilling tube
Operating pressure max. 1 bar max. 1 bar
Operating temperature -20 °C to +80 °C -20 °C to +80 °C
Float SK 610 SK 221
Min. fluid density 0.80 kg/dm³ 0.85 kg/dm³
Lengths (all versions) 280, 370, 500 mm (Standard) variable to max. 1500 mm
Material/Version MS VA
Float rigid PU 1.4571
Immersion tube Brass 1.4571
Flange (DIN 24557) PA PA
Weight at L=280 mm
Each 100 mm add
approx. 200 g
approx. 30 g
approx. 300 g
approx. 50 g
Includes:
Mounting screws (quantity 6) and rubberised cork seal.
Options
Stilling tube (SSR) Brass VA
Level switching output K10 W11
Function NO/NC* Change-over contact
Voltage max. 230 V AC/DC 48 V AC/DC
Switching current max. 0.5 A 0.5 A
Contact load max. 10 VA 20 VA
Min. contact spacing 40 mm 40 mm
*NO = falling NC contact / NC = falling NO contact
Temperature contact TK TM
Number of temp. contacts 1 2
Voltage max. 230 V AC/DC 230 V AC/DC
Switching current max. 2.5 A 2 A
Contact load max. 100 VA 100 VA
Function NC* NC*
Switching point °C 50/60/70/80 50/60/70/80
Switching point tolerance ± 3 K ± 5 K
Hysteresis max. 10 K ± 3 K 18 K ± 5 K
Function NO* NO*
Switching point °C 50/60/70/80 50/60/70/80
Switching point tolerance ± 3 K ± 5 K
Hysteresis max. 10 K ± 3 K 26/35/40/45 K ± 5 K
*NO= NO contact / NC = NC contact Other temperatures and versions with
2 x TK contact available upon request
Temperature signal
Temperature sensor Pt 100 Class B, DIN EN 60 751 Tolerance ±0.8 °C
Temperature transmitter KT
Temperature sensor Pt100 Class B, DIN EN 60 751
Measuring range 0 °C to +100 °C
Operating voltage (UB) 10 - 30 V DC
Output 4 - 20 mA
Burden Ω max. = (UB -7.5 V) / 0.02 A
Accuracy ± 1 % from end value
Other measuring ranges available upon request
18 Bühler Technologies GmbH BE100019 ◦ 08/2020