Endress+Hauser OFTE20 User manual

Operating Instructions
Point level switch
OFTE20
BA01325O/09/EN/04.22-00
71573627
2022-05-31

Point level switch Table of contents
3
Table of contents
1 Important document
information ..................... 4
1.1 Document function ................... 4
1.2 Document conventions ................ 4
2 Safety instructions .............. 6
2.1 Requirements for the personnel ........ 6
2.2 Intended use ........................ 6
2.3 Workplace safety .................... 6
2.4 Operational safety ................... 6
3 Identification .................... 7
3.1 Nameplate .......................... 7
3.2 Name and address of manufacturer ..... 7
4 Mounting ........................ 7
4.1 Incoming acceptance, transport,
storage ............................. 7
4.2 Installation conditions ................ 8
4.3 Installation instructions ............... 9
4.4 Post-installation check ............... 13
5 Wiring .......................... 13
5.1 Connection instructions .............. 13
5.2 Quick wiring guide .................. 14
5.3 Post-connection check ............... 16
6 Operation ...................... 17
6.1 Setting the switching threshold
(sensitivity) ........................ 17
6.2 Rotational movement display ......... 17
6.3 Indicator light (optional) ............. 18
6.4 Testing the internal switch ........... 18
7 Commissioning ................ 19
7.1 Post-installation and post-connection
check ............................. 19
7.2 Setting the switching pressure
(sensitivity) ........................ 19
7.3 Switching on the device .............. 19
8 Troubleshooting ............... 19
8.1 Point level switch with rotation
monitoring ........................ 20
9 Maintenance .................. 20
9.1 Cleaning ........................... 20
10 Repair .......................... 21
10.1 General information ................. 21
10.2 Spare parts ........................ 21
10.3 Return ............................ 21
10.4 Disposal ........................... 21
11 Technical data ................. 22
11.1 Input .............................. 22
11.2 Output ............................ 22
11.3 Power supply ....................... 22
11.4 Performance characteristics .......... 23
11.5 Mounting .......................... 24
11.6 Environment ....................... 25
11.7 Process ............................ 25
11.8 Mechanical construction ............. 26
11.9 Operability ......................... 28
11.10 Certificates and approvals ............ 28
11.11 Accessories ........................ 28

Important document information Point level switch
4
1 Important document information
1.1 Document function
These Operating Instructions contain all the information required in the various life cycle
phases of the device: from product identification, incoming acceptance and storage, to
installation, connection, operation and commissioning, through to troubleshooting,
maintenance and disposal.
1.2 Document conventions
1.2.1 Safety symbols
DANGER
This symbol alerts you to a dangerous situation. Failure to avoid this situation will result in
serious or fatal injury.
WARNING
This symbol alerts you to a dangerous situation. Failure to avoid this situation can result in
serious or fatal injury.
CAUTION
This symbol alerts you to a dangerous situation. Failure to avoid this situation can result in
minor or medium injury.
NOTICE
This symbol contains information on procedures and other facts which do not result in
personal injury.
1.2.2 Electrical symbols
Symbol Meaning
Direct current
Alternating current
Direct current and alternating current
Ground connection
A grounded terminal which, as far as the operator is concerned, is grounded via a
grounding system.
Potential equalization connection (PE: protective earth)
Ground terminals that must be connected to ground prior to establishing any other
connections.
The ground terminals are located on the interior and exterior of the device:
• Interior ground terminal: potential equalization is connected to the supply network.
• Exterior ground terminal: device is connected to the plant grounding system.

Point level switch Important document information
5
1.2.3 Symbols for certain types of information
Symbol Meaning Symbol Meaning
Permitted
Procedures, processes or actions that
are permitted.
Preferred
Procedures, processes or actions that
are preferred.
Forbidden
Procedures, processes or actions that
are forbidden.
Tip
Indicates additional information.
Reference to documentation
A
Reference to page
Reference to graphic
1.
,
2.
,
3.
… Series of steps
Result of a step Visual inspection
1.2.4 Symbols in graphics
Symbol Meaning
1, 2, 3 ... Item numbers
1.
,
2.
,
3.
… Series of steps
A, B, C, ... Views
A-A, B-B, C-C, ... Sections
-
Hazardous area
Indicates the hazardous area.
.
Safe area (non-hazardous area)
Indicates the non-hazardous area.
1.2.5 Tool symbols
Symbol Meaning
A0011220
Flat-blade screwdriver
A0011221
Allen key
A0011222
Open-ended wrench
A0013442
Torx screwdriver

Safety instructions Point level switch
6
2 Safety instructions
2.1 Requirements for the personnel
The personnel for installation, commissioning, diagnostics and maintenance must fulfill the
following requirements:
‣Trained, qualified specialists must have a relevant qualification for this specific function
and task.
‣Are authorized by the plant owner/operator.
‣Are familiar with federal/national regulations.
‣Before starting work, read and understand the instructions in the manual and
supplementary documentation as well as the certificates (depending on the application).
‣Follow instructions and comply with basic conditions.
The operating personnel must fulfill the following requirements:
‣Are instructed and authorized according to the requirements of the task by the facility's
owner-operator.
‣Follow the instructions in this manual.
2.2 Intended use
The device must only be used as a point level switch for specific bulk solids (see Technical data
→  25).
• The device may only be operated when installed.
• The manufacturer accepts no liability for damages resulting from improper or non-
designated use. It is not permitted to convert or modify the device in any way.
2.3 Workplace safety
When working on and with the device:
‣Wear the required personal protective equipment as per national regulations.
2.4 Operational safety
Risk of injury!
‣Operate the device only if it is in proper technical condition, free from errors and faults.
‣The operator is responsible for ensuring trouble-free operation of the device.
Modifications to the device
Unauthorized modifications to the device are not permitted and can lead to unforeseeable
dangers:
‣If modifications are nevertheless required, consult with the manufacturer.

Point level switch Identification
7
3 Identification
3.1 Nameplate
Point Level Switch
IP66
DMT 01 ATEX E 040
II 1/2D T110°C
Ta= -20°C...+60°C
230VAC 3,5VA contact ratings max.
250VAC / 6A cos =1j
S/N: XXXXXXXXXXXX
2013 OFTE20-xxxxxxxxxxx
1
2
3
45
6
8
7
0044
!
XXXXXXXXXXXXXXXXXXXX
A0023503
 1 Nameplate of the OFTE20 point level switch (example)
1 Device name
2 Housing degree of protection
3 Manufacturer's address
4 Approvals (optional)
5 Serial number
6 Year of manufacture and order code
7 Output values
8 Power supply and ambient temperature range
3.2 Name and address of manufacturer
Name of manufacturer: Endress+Hauser Wetzer GmbH + Co. KG
Address of manufacturer: Obere Wank 1, D-87484 Nesselwang or www.endress.com
4 Mounting
4.1 Incoming acceptance, transport, storage
Compliance with the permitted environmental and storage conditions is mandatory. Precise
specifications are provided in the "Technical data" section →  22.
4.1.1 Incoming acceptance
On receipt of the goods, check the following points:
• Is the packaging or the content damaged?
• Is the delivery complete? Compare the scope of delivery against the information on your
order form.

Mounting Point level switch
8
4.1.2 Transport and storage
Please note the following:
• Pack the device so that is protected against impact for storage and transport. The original
packaging offers the best protection for this.
• The permitted storage temperature is –20 to 60 °C (–4 to 140 °F).
4.2 Installation conditions
Correct and incorrect installation positions are indicated in →  2,  8.
The device must be protected against direct sunshine. A weather protection cover is available
as an accessory, see the "Accessories" section →  29.
The dimensions of the device are provided in the "Technical data" section →  16,  26.
1
3
2
4
~200 (7.87)
5
6
7
8
A0021567
 2 Orientations of the point level switch, dimensions in mm (in)
Permitted orientations Forbidden orientations
1: Vertical from the top 6: In direction of solids flow
2: Angled from the top 7: Installation coupling too long
3: From the side 8: Horizontal with shaft length >300 mm (11.8 in)
4: From the side with protective cover against falling
solids
5: From the bottom (device must be protected
against shock-type loads)
Ambient temperature range
–20 to 60 °C (–4 to 140 °F)
Medium temperature range
–20 to 80 °C (–4 to 176 °F)

Point level switch Mounting
9
Mechanical load of optional indicator light
The optional indicator light must be protected against mechanical load (impact energy > 1 J).
More information is provided in the "Technical data" section →  25.
4.3 Installation instructions
NOTICE
The device can be damaged if handled incorrectly during installation
‣Do not turn the housing to tighten the process connection. Once the process connection
has been tightened, the housing can be aligned so that the cable entries point downwards.
1
2
3
A0017361
 3 Installation of the standard version
1 Attach sealing ring (1) 60x48x3 mm (2.36x1.89x0.12 in).
2 Insert the rotary paddle into the connecting flange (3). Note: Pay attention to the maximum flange
depth of the connection. With the standard rotary paddle, installation in flange connections is
permitted up to a sleeve length ≤ 40 mm (1.57 in). For sleeve lengths > 40 mm (1.57 in)only the
version with hinged rotary paddle can be used. It must be possible to insert the rotary paddle without
force.
3 Tighten nut with open-ended wrench AF 60 (2).
NOTICE
The device with hinged rotating paddle does not function correctly when the transport
lock is secured.
‣Remove the transport lock (plastic net around the rotating paddle) prior to installation.

Mounting Point level switch
10
1
2
1. 2. 3.
A0017363
 4 Installation of the version with hinged rotary paddle
1 Attach sealing ring (1) 60x48x3 mm (2.36x1.89x0.12 in).
2 Slide the rotary paddle into the connecting flange (3).
3 Tighten nut with open-ended wrench AF 60 (2).
4.3.1 Turning the housing to the right position
A0017364
 5 Correct housing position
4.3.2 Installation of the flange version
The flange version is available as an accessory. The dimensions are provided in the "Technical
data" section →  30.

Point level switch Mounting
11
1
2
3
A0018473
 6 Installation of the flange version
1 Attach sealing ring (1) 60x48x3 mm (2.36x1.89x0.12 in) and insert rotary paddle into connecting
flange.
2 Tighten nut (2) with open-ended wrench AF 60.
3 Secure the device using 4 screws (not included in the scope of delivery).
4.3.3 Mounting the weather protection cover
The weather protection cover is available as an accessory and can be installed without
disassembling the point level switch. The dimensions are provided in the "Technical data"
section →  19,  30.

Mounting Point level switch
12
A0017698
 7 Mounting the weather protection cover
To protect the device from sunlight, arrange the weather protection cover in such a way
that provides optimum shade for the device.
4.3.4 Installation in hazardous areas
When installing the point level switch in a hazardous area, the securing screw must be
tightened to prevent the cover from opening.
Additional installation instructions for the hazardous area are provided in the separate Ex
documentation for the device (optional).
T10
A0017368
 8 Tightening the cover securing screw. This is a combined screw; a flat-blade screwdriver can be
used as an alternative to a T10 Torx screwdriver.

Point level switch Wiring
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4.4 Post-installation check
• Are the seals undamaged?
• Is the process connection securely tightened?
• Do the cable entries point downwards and are they tightened?
• Is the cover securely closed and the securing screw securely tightened?
5 Wiring
5.1 Connection instructions
LWARNING
Danger! Electric voltage!
‣The entire connection of the device must take place while the device is de-energized.
LCAUTION
Pay attention to additional information provided
‣The protective ground conductor must be connected before any other connection is
established.
‣Before commissioning the device, make sure that the supply voltage matches the voltage
specifications on the nameplate.
‣Provide a suitable switch or power-circuit breaker in the building installation. This switch
must be provided close to the device (within easy reach) and marked as a circuit breaker.
‣An overload protection element (rated current ≤ 10 A) is required for the power cable.
NOTICE
High temperatures can damage the cables and the device
‣Use cables that are suitable for temperatures 10 °C (18 °F) above the ambient temperature.
NOTICE
IP66 protection is not provided if the protection caps supplied are used for the cable
entries
‣The protection caps supplied are designed to protect against contamination during
transport and storage. Use a suitable dummy plug to seal any cable entry that is not used
during operation.

Wiring Point level switch
14
5.2 Quick wiring guide
H1 *Option
Test
A0017295
 9 Terminal assignment of the point level switch
Symbol Description Symbol Description
 Protective ground H1 Connection for signaling empty/full
status detection (optional)
N (AC), Power supply N/L-
L- (DC) 11 Changeover contact
L1 (AC), Power supply 12 Normally closed contact
L+ (DC) 13 Normally open contact

Point level switch Wiring
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5.2.1 Switching states
11
13
12
12
A
B
C
11
13
12
11
13
12
3
A0017628
1 = Indicator
light (optional,
non-Ex only)
2 = Full
signaling
3 = Refill
signalling
Shaft rotation Internal light
A OFF OFF ON YES ON
B ON ON OFF NO ON
C (only with
optional rotation
monitoring)
OFF ON OFF NO Flashes

Wiring Point level switch
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5.2.2 Inserting the cable
A0017367
 10 Removing the housing cover and inserting the cables
A0017366
 11 Connecting the cables to the terminals
5.3 Post-connection check
Device condition and specifications Notes
Are cables or the device damaged? Visual inspection
Electrical connection Notes
Does the supply voltage match the information on the
nameplate?
→  1,  7
Are the mounted cables connected correctly and strain-
relieved?
-
Are the cable glands securely tightened? -

Point level switch Operation
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6 Operation
LWARNING
The device is not explosion-protected if the housing is open.
‣The device may only be opened in the hazardous area if no supply voltage is applied.
Therefore the device may only be operated in a de-energized state or outside the hazardous
area.
6.1 Setting the switching threshold (sensitivity)
The switching threshold can be set in 3 stages via an operating element that is accessible from
above. The threshold can also be set during operation (in the non-hazardous area):
• Minimum: 80 g/l (4.99 lb/ft³)
• Adjustable in 3 stages depending on the density of the bulk solids: low, medium (factory
default), high
12
1.
2.
2.
A0017352
 12 Setting the switching threshold
Setting the switching pressure
1. Move the operating element counterclockwise as illustrated in the graphic.
2. Move the operating element to the desired position and let it click into place.
6.2 Rotational movement display
The shaft's rotational movement is displayed by a ratchet disk fitted on the drive axle of the
rotary paddle. The viewing area is lit up by an LED to make it easier to see. The rotational
movement of the disk, and therefore also the shaft, can be checked through an inspection
opening in the cover of the internal compartment when the cover is closed.

Operation Point level switch
18
*Option
A0017353
 13 Inspection glass to observe rotational movement
6.3 Indicator light (optional)
The point level switch is optionally fitted with an indicator light that lights up when the rotary
paddle stops.
6.4 Testing the internal switch
When the housing cover is open, the function of the internal switch to switch off the motor
can be checked by inserting a screwdriver into the opening provided in the electronics cover
and by moving the handle in the direction of the arrow.
A0017369
 14 Testing the internal switch

Point level switch Commissioning
19
7 Commissioning
7.1 Post-installation and post-connection check
Checklists:
• Post-installation check →  13
• Post-connection check→  16
7.2 Setting the switching pressure (sensitivity)
The switching threshold can be adapted to the weight of the bulk solids in 3 stages via an
operating element that is accessible from above (also possible during operation):
• Minimum: 80 g/l (4.99 lb/ft³)
• Adjustable in 3 stages depending on the density of the bulk solids: low, medium (factory
default), high
7.3 Switching on the device
The shaft starts to turn as soon as the supply voltage is switched on. The rotational movement
can be observed from the outside.
*Option
A0017353
 15 Window to observe rotational movement
8 Troubleshooting
Functional testing of the point level switch by testing the internal switch →  14,  18

Maintenance Point level switch
20
8.1 Point level switch with rotation monitoring
The table below shows the output signal of the point level switch with rotation monitoring for
overfill protection.
Rotation monitoring of the point level switch (optional)
Power supply Motor Output signal of
"full" sensor
Internal light
Normal operation
On Shaft turns - On
On Shaft does not turn,
rotating paddle is
covered
Full On
Event of fault
On Shaft does not turn,
rotating paddle is not
covered
Full Flashes
Off Full Off
If the rotation monitoring system detects an error, a "full" alarm is signaled and the light in the
electronics housing flashes.
Function testing of the point level switch
Operate the internal switch
1. Insert a screwdriver or another suitable tool in the opening provided in the electronics
cover and move it in the direction indicated, see testing the internal switch
→  14,  18.
 The switch is operated and the empty/full alarm is reset.
2. Wait for the error detection time to elapse (approx. 25 s).
 If no rotational movement is detected during the error detection time, the device
signals the full or empty alarm again and the light in the electronics housing
flashes.
9 Maintenance
No special maintenance work is required for the device.
9.1 Cleaning
A clean, dry cloth can be used to clean the device.