Nice LP21 User manual

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LP21/LP22 Installation instructions en Sensors
1 Safety instructions
Availability of documents
The Operating manual must be available at all times. The instructions must be read and understood before
the device is used for the first time, and adhered to at all times.
Service only by trained electricians
All work on the device (assembly, connection, commissioning, decommissioning, maintenance, repair,
measurements and settings) may only be carried out by qualified electricians with relevant training on the
prevention of accidents.
Intended use
The device may only be used for the purpose intended by the manufacturer. Consult the chapter relating to
intended use.
Improper use
The device is subject to the manufacturer’s warranty conditions valid at the time of purchase. The
manufacturer will not accept any responsibility for unsuitable or incorrect manual or automatic parameter
settings performed on a device or the inappropriate use of a device.
Improper repairs
Repairs may only be performed by the manufacturer. Failure to comply will endanger the safety of the device
and renders the warranty null and void.
Permitted voltages
The voltage supply must meet the requirements for safety extra-low voltage (“Circuits and power sources of
limited power” SELV).
Regulations on electrical voltage
Users of devices which come into contact with electrical voltage must comply with the valid regulations.
These are in particular, but with no claim to completeness, EN 60335, EN 60065, EN 50110, and the fire and
accident-prevention regulations.
Comply with national regulations
All work on the device and its installation must be carried out in accordance with the specifications of the
national electrical regulations and local regulations.
Essential safety equipment
The device may not be used as a safety component as defined by the Machinery Directive 2006/42/EG, the
Construction Products Regulation 305/2011/EU or other safety regulations. Systems with a hazard potential
require additional safety equipment!

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2 Proper use
Induction loop detectors such as traffic detectors are operated in combination with various induction loops
and electronic controller, such as frequency converters and PLC controller.
Areas of application are systems in the areas of traffic engineering, door and barrier controller, parking and
tunnel monitoring as well as traffic light systems.
The traffic detectors of the LP21/LP22 series are intended for installation in a controller cabinet or a similar
housing.
WARNING
Comply with the technical data
The detector may only be operated with the prescriped supply voltages. Take note of the technical data
before installation.
WARNING
Protection from environmental influences
The device must be installed in a location where it will not sustain damage from heat, dripping water,
moisture or dust.
Incorrect use
Alterations to the device and the use of spare parts and additional devices not sold or recommended by the
manufacturer of the device may result in injuries and damage resulting from electric shocks and fires. Such
actions result in a disclaimer of liability and forfeiture of the warranty.
Impermissible interference with the housing
Do not open the housing. This poses a danger to persons and the device functions and result in a disclaimer
of liability and forfeiture of the warranty.

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3 Product overview
3.1 Housing dimensions
Fig.1: LP21/LP22 side view
Fig.2: LP21/LP22 front view

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3.2 Device components
Fig.3: Traffic detector LP21/LP22
Index
Component
Description
A
Loop channel LEDs 1 (red + blue)
Status indicators for the loops and the detector
B
DIP switch 1
Basic settings for the detector
C
Loop channel LEDs 2 (red + blue)
Status indicators for the loops and the detector
D
DIP switch 2 (LP22 variant)
Basic settings for the detector
E
USB connection
Updates
F
Reset button
Factory settings or fresh adjustment
G
Loop inputs (orange)
Connections for induction loops
H
Output 1 terminal block:
•Relay output 1 (yellow)
Signal outputs for controller
I
Mounting bracket
Mounting device for TS35 DIN rail
J
Output 2 terminal block:
•Relay output 2 (red)
Signal outputs for controller
K
AC/DC connection (blue)
Connections for power supply
Tab.1: LP21/LP22 Traffic Detector

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3.3 Technical data
Specifications
Housing
Plastic housing, ABS, blue
Mounting method
TS35 DIN rail
Dimensions
22.5 x 79.0 x 81.0 mm (W x H x L, without
terminals)
Power supply (1 x blue)
2-pole terminal block (see Note 3)
10 –30 VDC / 10 –26 VAC (SELV)
max. 2 W
Power consumption
Typically 500 mW
Protection class
III
Protection type
IP20
Environmental conditions
•permitted operating temperature
-37 –+70 °C
•permissible storage temperature
-40 –+85 °C
•relative humidity
< 95 % (non-condensing)
Loop properties
•max. inductivity range
20 - 700 H (see note 1)
•recommended inductivity range
100 –300 H
•operating frequency
30 –130 kHz
•cable length
200 m
•internal resistance
20 Ω (including cable)
•min. insulation resistance to earth
100 kΩ (constant, including cable)
•insulation voltage, loop inputs
1 kV (galvanic isolation)
Cycle and reaction time
12 ms (independent of loop channels)
Maximum speed for vehicles
•presence detection
Max. 200 km/h
•direction detection (dual-channel variants)
Max. 200 km/h (at loop head distance of 2 m)

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Specifications
Inputs
•1 x loop (1 x orange, single-channel variants)
2-pole terminal block (see Note 3)
•2 x loop (1 x orange, dual-channel variants)
4-pole terminal block (see Note 3)
Outputs
•2 x relays (1 x yellow, 1 x red)
3-pole terminal block (see Note 3)
Max. 48 V (AC/DC), 2 A, 60 W, 125 VA (SELV)
Min. 1 mA / 5 V (see note 2)
Configuration switch 1
8-pole DIP switch
Configuration switch 2 (dual-channel variants)
4-pole DIP switch
LED status indicator
1 x blue and 1 x red (per loop channel)
Reset button
Push button
PC interface
USB port, type mini AB
Tab.2: Specifications
NOTE
1) Limitations on loop inductance
For loop inductances outside the recommended range, only one frequency level may be available.
For very small loop inductances, the maximum loop resistances are lower.
2) Current load of the relay contacts
The rigid gold plating on the relay contacts will be destroyed if the switching current exceeds 100
mA. Relays with contacts that are prestressed in this manner can only reliably switch currents over
100 mA!
3) Terminal block data
Grid dimension 5.0 mm, conductor cross-section 0.25 - 2.5 mm², AWG 24-12

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4 Product description
Induction loop detectors such as traffic detectors are electronic sensors for inductive detection of metallic
objects. Using induction loops, for example, vehicles are detected, and depending on the device, their design
and direction of movement.
The traffic detectors are operated in combination with various induction loops and electronic controller, such
as frequency converters or PLC controller.
The areas of application are, for example, the detection, monitoring and counting of vehicles in the areas of
traffic engineering, door and barrier controller, parking and tunnel monitoring as well as traffic light systems.
4.1 Product versions
The Traffic detector is available in the following versions:
Product name
Features
LP21 (1 CHANNEL)
•1 Channel for one induction loop
•2 Relay outputs
•8-pole DIP switch for configuration
•USB diagnostic interface
•Reset button
•24 V supply voltage
•Top hat rail mounting
•Plastic housing
LP22 (2 CHANNEL)
•2 Channels for two induction loops
•2 Relay outputs
•8-pole DIP switch for configuration
•4-pole DIP switch for configuration
•USB diagnostic interface
•Reset button
•24 V supply voltage
•Top hat rail mounting
•Plastic housing
Tab.3: Product versions
NOTE
Systems with high switching frequency
The use of detectors with digital outputs is recommended for systems with a high switching frequency. A
restricted switching cycle limits the operational life of relay contacts.

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4.2 Product characteristics
The traffic detectors have the following properties:
•1 loop channel (LP21) or 2 loop channels (LP22)
•2 potential-free relay outputs with changeover contact
•8-pole DIP switch for configuration
•4-pole DIP switch for advanced configuration (LP22)
•2 or 4 LEDs for the indication of detector and loop states
•USB interface
•Connection for power supply (AC/DC)
•Galvanic isolation between loops and electronics
•Automatic adjustment of the device after switch-on
•Continuous adjustment of frequency drifts to suppress environmental influences
•Sensitivity independent of loop inductance
•Fixed hold times regardless of the loop coverage
•Direction detection based on two loop channels (LP22)
•Multiplexing prevents mutual interferences of the loop channels (LP22)
•Compact plastic housing for mounting on DIN rail in control cabinet
4.3 Product functions
The traffic detectors offer the following setting options:
•Switching between two frequency levels
•Output as presence or pulse signal or of direction (dual-channel variant LP22)
•Response threshold adjustable in 4 steps with DIP switch
•Hold time adjustable: 5 minutes or infinite with DIP switch
Advanced functions of the dual-channel variants:
•Selection of direction logic

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4.3.1 Vehicle detection
Whether a metallic object is located in the loop area is identified via an LC oscillator (electrical oscillatory
circuit). The channel output is switched according to the output function configured.
4.3.2 Output signals
Depending on the output configuration, presence, pulse or direction signals and direction logics (LP22) as
well as loop faults are output.
For the pulse signal, it is also possible to select whether an output should occur when a loop is driven past or
vacated.
In addition to inversion of the output signal, both outputs can individually be permanently switched on or off.
4.3.3 Alignment of the loop channels
When the detector is switched on or the reset button on the front is pressed for one second, an alignment of
the loop channels is run.
If there has been an interruption of power, an automatic alignment only takes place if the operating voltage
has been interrupted for at least 0.5 seconds. Alignment takes around one second if no vehicles drive over
the loop in this time.
External influences on the loop frequency may result in longer alignment times, and their causes must be
determined and eliminated.
4.3.4 Scanning of the loop channels
The dual-channel traffic detector LP22 can evaluate two loop channels.
The timed scanning of the loops is carried out in multiplex mode. They are connected to the common
oscillatory circuit oscillator over a multiplexer. This prevents the loops interfering with each other.
The connected induction loops are switched on and off in rapid succession. Current is only ever supplied to
one loop at a time. This means that both loops can be operated at the same frequency.
The cycle time of a scan in multiplex mode is 12 ms.
4.3.5 Loop error detection
Loop closure and loop break are identified as loop errors.
If no induction loop is connected to the loop channel, this corresponds to a loop break error status.
Once a loop error has been detected, the loop channel switches off. This may cause the available operating
modes to be restricted, for example direction detection.

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5 Description of connections
In the following section, the connections for the inputs and outputs are described.
5.1 Power supply
The detector can be operated with direct or alternating current, according to the requirements for Safety
Extra-Low Voltages (SELV) of Protection Class III.
WARNING
Note the permitted power supply
Comply with the technical data and safety instructions!
The power supply is connected to the blue terminal block.
VCC
Plus
GND
Ground
Fig.3: Power supply connection (blue)
5.2 Loop inputs
Up to two analogue inputs for the induction loops on the terminal block are located on the underside of the
traffic detector. The terminal block is either 2-pole or 4-pole, depending on the product variant.
The induction loops are connected to the orange terminal blocks as shown in the illustration.
L1a
L1b
Induction loop channel 1 connections
L2a
L2b
Induction loop channel 2 connections
(dual-channel variant LP22)
Fig.4: Loop connections (orange)

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5.3 Signal outputs
The relay variants are intended particularly for situations which require mechanical switches with high power
outputs.
5.3.1 Relay outputs with changeover contact
The relays are designed as changeover contacts. Thus the outputs can be connected as normally closed
(NC) or as normally open (NO). The relays are potential-free andsuitable for many different types of
switching modes.
All signal outputs can be inverted . In this case, when the power supply is turned on, normally open contacts
function as normally closed contacts, and vice versa. This happens by switching between open-circuit and
closed-circuit principle.
Loop malfunctions can also be interpreted as loop covered or as loop free.
Status
Normally closed contact (NC)
Normally open contact (NO)
Not inverted (open-
circuit principle)
Inverted (closed-
circuit principle)
Not inverted (open-
circuit principle)
Inverted (closed-
circuit principle)
Power supply off
Detector ready, loop
free
Loop covered
Tab.4: Switching states of the signal outputs
The analogue outputs of the relay variants are connected to the red and yellow terminal blocks according to
the following illustration.
NO1
NO2
Normally open contact to output 1 (NO1) or output 2
(NO2)
COM1
COM2
Common contact to output 1 (COM1) or output 2
(COM2)
NC1
NC2
Normally closed contact to output 1 (NC1) or output 2
(NC2)
Fig.5: Relay connections 1 (yellow) and 2 (red)

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6 Assembly and electrical installation
In the following section, assembly and electrical installation are described.
NOTE
Illustrations and technical data on the device
You can find illustrations and technical data on the housing and connections in the sections at the
beginning of this document.
6.1 Assembly on the DIN rail TS35
Prerequisites
Assembly conditions
Tools: none
Mounting device: DIN rail TS35 (top hat rail)
Fixing to the top hat rail
1. Place on the device from above with the groove on the top hat rail and lock the clip underneath.
2. Check that it is sitting securely.
→The detector is ready for commissioning.

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6.2 Connecting the power supply
WARNING
Maintain the permitted voltages
The following voltage supplies are permitted:
•10 - 30 VDC
•10 - 26 VAC
Consult the chapter Description of connections.
PREREQUISITES
Connect the inputs and outputs with no voltage present
All inputs and outputs must be connected before switching on the voltage supply.
TOOLS
•Insulated flat-head screwdriver (width: 2 –3 mm)
Connecting the power cable
1. Follow the warning and safety instructions and take the appropriate precautions.
2. If necessary, pull the terminal block out of the socket.
3. Loosen the screws on the blue terminal block.
4. Insert up to 5 mm of stripped supply cable into the slots at the side of the blue terminal block and fix.
5. Tighten the respective screw.
6. If necessary, insert the terminal block back into the blue 2-pole socket.
→The supply cable is firmly attached to the terminal block with no exposed wires.
Connect the power cable to the power source
1. Comply with the warnings and safety instructions for the external device.
2. Follow the manufacturer’s instructions on wiring the outputs on the external device.
→The power cable is connected to the power source.

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6.3 Connect the relay outputs
TOOLS
Insulated slotted screwdriver (width 2 –3 mm)
Connecting the relay outputs
1. Follow the warning and safety instructions and take the appropriate precautions.
2. If necessary, pull the red or yellow terminal block out of the socket.
3. Loosen the screws on the blue terminal block.
4. Insert up to 5 mm of stripped cable into the slot on the side of the terminal block and fasten.
5. Tighten the screw.
6. If necessary, insert the terminal block back into the red or yellow 3-pole socket.
→The cables of the relay outputs are firmly attached to the terminal block with no exposed wires.
Connect the relay cable to the external device
1. Comply with the warning and safety instructions for the external device.
2. Follow the manufacturer’s instructions on wiring the outputs on the external device.
→The relay outputs are connected to the signal outputs on the external device.

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6.4 Installing the induction loops
•The induction loops must be installed with a clearance of min. 15 cm to fixed metal objects and 1 m to
mobile metal objects. The clearance to the surface of the final road surface should not amount to more
than 5 cm.
•It is vital that the loop cable is installed separately from the supply lines
•A normal single pole cable with a cross section of 1.5 mm² must be used as a loop cable.
•If buried in the ground, the cable must be equipped with suitable insulation. If you use hot sealing
compound, make sure the cable has a suitable temperature stability.
•Induction loops should preferably be realised in squares or at right angles. If it is not possible to use
finished loops, they should be installed in a groove cut in the road surface as shown in the figure
below. The loop cable must be fixed well in the groove. Then fill the groove with sealing compound.
The corners should have a 45° angle to avoid damage to the cable insulation.
Fig.7: Installing the loops
•When installing the cable, comply with the number of turns specified in the table.
Scope of the induction loop
Number of turns
Smaller than 3 m
6
3 - 4 m
5
4 - 6 m
4
6 -12 m
3
Larger than 12 m
2
Tab.5: Number of turns on the loop cable
•The two cable ends leading from the induction loop to the detector (loop supply line) must be twisted
with min. 20 strokes/m.
•Avoid dividing the cable. Should is be necessary to divide the cable, protect the clamp points against
moisture penetration with cast resin collars.
30-50 mm
8 mm

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6.5 Connecting the induction loops
RECOMMENDATIONS
The requirements for the induction loops differ according to the area of application. Allow the supplier to
advise you on installation of the induction loops.
PREREQUISITES
The induction loops are already installed and ready for use.
TOOLS
•Insulated slotted screwdriver (width: 2 –3 mm)
•Induction loops for the respective area of application
Connecting the induction loops
1. Follow the warning and safety instructions and take the appropriate precautions.
2. If necessary, pull the orange terminal block out of the socket.
3. Loosen the screws on the blue terminal block.
4. Insert up to 5 mm of stripped cable into the slot on the side of the terminal block and fasten.
5. Tighten the screw.
6. If necessary, insert the terminal block back into the orange 4-pole socket.
→The induction loops are firmly attached with no exposed wires.

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7 Commissioning
Prerequisites
Assembly and electrical connection
•The system is not in use.
•All work must be carried out by qualified specialist personnel.
•All available cables are firmly attached to the terminal block.
•The terminal blocks are sited on the input and output sockets of the same colour.
•The detector is firmly mounted on the top hat rail.
Tools
Tools for the system
Always comply with the manufacturer’s instructions!
No tools are required to commission the system.
Commissioning the detector
1. Define the settings with the DIP switches.
2. Switch on the power supply to the detector.
→The LP21/LP22 series detectors automatically run a test of the induction loops as well as a
frequency alignment.
→The detector is ready for operation when the blue LEDs are continuously lit. There is more
information in the chapter on LED indicators.
3. Start up all components of the system (comply with the manufacturer’s instructions).
4. Carry out a functional test of the system (comply with the manufacturer’s instructions).
→The detector is ready for continuous operation.
NOTE
Optimising the detector settings
The device settings can be changed using the DIP switch while it is operating.

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8 Description of functions
In the following section the indicator and control elements are described.
NOTE
Information in this document
This document refers to the default settings or default values defined by the manufacturer. The factory
settings of customer variants may differ from the manufacturer’s specifications. Please observe the
instructions on the device, as well as the documents supplied with it.
8.1 LED status indicators
The LEDs (light emitting diodes) on the front side indicate the state of the loops and the detector.
There are two LEDs for each loop channel:
•The red LED indicates the coverage status of the respective loop
•The blue LED indicates the operating status of the detector
Red LED
Blue LED
Description of status
No power supply, detector inactive
Detector ready, loop connected, no object detected
Detector ready, loop connected, object detected
No loop connected, loop break, loop closure
1 Hz
Ready for operation following earlier, now rectified, loop error
5 Hz
Frequency alignment is running
After frequency adjustment, both LEDs simultaneously display the set loop
frequency in a flash code (see Flash code illustrated example)
Tab.6: LED signal colours
Key to LED symbols
Lit up
Off
Flashing
Frequency
LED flash code following a frequency alignment
Fig.8: LED display of loop frequency

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NOTE
LED position
The LEDs for the loop channel 1 are located at the top or side of the device, for loop channel 2 are in the
middle.
8.2 DIP switch settings
Function
Description
Sensitivity
Switch-on threshold for signal output when the loop is covered
Frequency level
Frequency of the loop resonant circuit in two levels
Hold Time until readjustment
Maximum duration of the output signal until automatic frequency
adjustment of the loop channel
Output signal 2 mode
Switching between continuous signal and pulse signal at output 2
Time of output signal 2
Time of output signal for activated pulse signal on output 2
Output signal inversion
Reversing the switching logic for the output signals (inversion)
Direction detection
Switching between presence and direction detection for both outputs
(2 channel variant LP22)
Direction logic
Evaluation logic of the direction of travel when loop is covered according
to the specific application (read the operating instructions!)
Tab.7: Description of the settings
8.2.1 DIP switch assignment of the LP21 variants
The single-channel variants have an 8-pole DIP switch for configuring the detector.
DIP
Designation
Function
1
Sense a
Loop 1 sensitivity
2
Sense b
Loop 1 sensitivity
3
Frequency
Frequency step
4
Hold time
Hold time until readjustment
5
Output 2
Output signal 2 mode
6
Edge 2
Output signal 2 time
7
Inv. Out 1
Output signal 1 inversion
8
Inv. Out 2
Output signal 2 inversion
Tab.8: DIP switch assignment (default)

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The following parameters can be adjusted with the DIP switch:
DIP switch
Position
Value
Sense a
ON
0.01% (high)
Sense b
ON
Sense a
OFF
0,04%
Sense b
ON
Sense a
ON
0,16%
Sense b
OFF
Sense a
OFF
0.64% (low)
Sense b
OFF
Frequency
OFF
low
ON
high
Hold time
OFF
5 minutes
ON
Infinite
Output 2
OFF
Pulse signal
ON
Continuous signal
Edge 2
OFF
on entering
ON
on leaving
Inv. Out 1
OFF
Output inverted
ON
Output not inverted
Inv. Out 2
OFF
Output not inverted
ON
Output inverted
Tab.9: Settings via DIP switch (LP21)