SWR ENGINEERING Dusty User manual

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1INTRODUCTION 3
1.1 Safety 3
1.2 Product overview 3
1.3 How does it work 3
2INSTALLATION 4
2.1 Selecting the installation location 4
2.2 Installing the sensor 6
3WIRING 7
4TECHNICAL SPECIFICATIONS 9
5DIMENSIONS 10
6OPERATION 11
7AUTO-SETUP 12
8MAINTENANCE 13
9TROUBLESHOOTING 13
9.1 No switching of the output signals 13
9.2 No sensor response after the auto-SETUP 13

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1 Introduction
1.1 Safety
Dusty requires 12-24 VDC power supply. 12-24 VDC voltage level is considered as safe.
Precautions:
The duct has to be opened at the installation and the maintenance.
Thereby some risks have to be considered:
• The flow of gas or dust can be hazardous to health.
• The flow can be inflammable, explosive or toxic.
• The gas can be hot or under pressure.
1.2 Product overview
The Dusty is a microprocessor-based, self-adjusting device, equipped with 2 switching contacts and a LED
in the front cover.
The Dusty is designed for filter bag leak detection. It is a compact unit consisting of a sensor and control
electronics built into an IP65 enclosure, which has been specifically designed for easy installation and
operation.
The Dusty is designed for applications at up to 2 bar and 140 °C.
1.3 How does it work
The Dusty works with its proven and reliable triboelectric technology whereby the interaction of dust
particles with the sensor rod causes a small electric charge, when the particles pass by and the sensor rod.
This small electric charge provides the signal to the sensor by the electronics, and the signal generated is
proportional to the dust level even if there is an accumulation of particles on the sensor rod. Experience has
shown that this method of sensoring dust level in gases offers accurate results with a minimum of
maintenance.

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2 Installation
2.1 Selecting the installation location
The best location for installation of the Dusty is in a duct section where the flow has its most even
distribution and the flow is as laminar as possible.
The optimal position would be in a horizontal or vertical section of the duct. There have to be no bends,
valves, dampers or other obstructions in a distance equal to a quintuple of the duct diameter in every
direction of flow to the sensor rod.
Fig 1: Recommended distances to bends (DN = Duct Diameter)

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In some applications a compromise has to be made and the sensor will have to be fitted in a position that
satisfies the majority of above requirements.
The Dusty must be attached to metal ductwork so that they will be electrically shielded from interference and
be provided with a grood grounding. For non-metal ducts, a section of the duct, approximately five diameters
in length, should be covered with a metal foil or fine-mesh on the periphery of the duct.
1. The unit shall be installed in a position, where the gas flow passes the sensor rod in a 90° angle.
2. In round cross-section ducts the unit can be installed in any position above the horizontal axis
(between 9 and 3 o’clock). (See figure 2a)
3. For square cross-section ducts, the unit must be positioned in the middle of the top or in the middle of
one of the sides. (See figure 2b)
4. Although the sensor is not affected by vibration, very high vibration levels should be avoided.
5. The units must not be installed in direct sunlight or in areas where the ambient temperature
is above 55 oC.
6. The sensor rod must not contact the opposite duct wall or any other obstacle inside the duct!
In cases of need the sensor rod can be shorten to a minimum length of 70 mm.
Fig. 2a: Round cross-section duct
Fig 2b: Square cross-section duct

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2.2 Installing the sensor
Once the location of the unit has been selected, the R1/2” male thread is welded on the duct wall.
Then the R1/2” female thread is screwed in until there is a tight connection to the process.
Caution:
Do not overtight the Dusty with the process, because it could cause damage to the sensor and electronics!
Do not open the hexagon socket screw to turn the head of the Dusty, because the cables could be torn off the board.

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3 Wiring
The required supply voltage for the Dusty is 12-24 VDC.
The Dusty is fit out with a 1 meter power and signal cable ready connected.
There are 4 pairs (8 wires) in the cable, 2 wires for 12-24 VDC and 2 for the switching contacts.
There remain 4 wires not referred, for factory service and diagnostics purposes.
Connect a 12-24 VDC power supply to the grey and pink wire.
The blue and grey wires are for the switching contacts.
Connection with M12 plug requires the following assignment:
PIN 1 = V- (0 V)
PIN 2 = V+ (12-24 V)
PIN 3 = switching contact 1
PIN 4 = switching contact 2
CONN1 pin number
wire colour
signal name
1
white
2
brown
3
green
4
yellow
Reserved for
service & diagnostics
5
grey
V– (0 V)
6
pink
V+ (12-24 V DC)
7
blue
switching contact 1
8
red
switching contact 2

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Signals and switching states
Situation
LED
Input
Input
Output
Output
PIN 5 grey
PIN 6 pink
voltage
PIN 5 / PIN 7
grey / blue
voltage
PIN 5 / PIN 8
grey / red
out / failure
out
0 VDC
0 VDC
0 VDC
0 VDC
supply
voltage
green
0 VDC
12-24 VDC
0 VDC
12-24 VDC
5x normal
dust level
yellow /
orange
0 VDC
12-24 VDC
12-24 VDC
0 VDC
20x normal
dust level
red
0 VDC
12-24 VDC
12-24 VDC
12-24 VDC

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4 Technical Specifications
Sensor
Measurement objects
Solid particles in a gas flow
Particle size
0,3 µm or larger
Measurement range
From 0.1 mg/m3
Range setup
Automatic
Process Temperature
Max. 140 °C
Ambient temperature
-20…+60 °C
Pressure
Max. 2 bar
Gas velocity
Min. 4 m/s
Humidity
95% RH (non-condensing)
Meassurement principle
Tribo-electricity (elektrostatic detection)
Damping time
10 sec
Output signals
• 2 solid switching contact states (max. current feed of 170 mA)
• 3-colour LED in the front cover
Alarm settings
Alert – 5x normal dust level
Alarm – 20 x normal dust level
Sensor rod
Stainless steel; length: 220 mm
Enclosure
Aluminium
Protection category
IP 65; dustEx 22 (optional)
Power supply
12–24 VDC
Power consumption
3W
Electrical connections
2 m cable; M12 connector (optional)
Cable (power + signal)
8 wires (shielded)
Process connection
R 1/2” male thread
Weight
Approx. 0.7 kg
This instrument conforms to the following standards:
Product standard – electrical equipment for measurement, control and
laboratory use – EMC requirement
Reference standard EN 61326
Publication year (1997);
Amendment(s) A1(1998), A2(2001), A3(2003)

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5 Dimensions
Fg. 3: Dimensions and structure of the Dusty

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6 Operation
The sensor measures the dust level in a gas flow by sensoring electrostatic discharge when charged by
dust particles hitting or passing near by the probe.
There are 2 switching contact states with a solid alarm output and a 3-colour LED in the front cover.
Switching of the contacts:
•normal dust level: contact 2 is ON (= connected).
•5x normal dust level: contact 1 is ON and contact 2 is OFF.
•20x normal dust level: contact 1+2 are OFF.
The alarm threshold values:
Alert: 5x normal dust level = limit 1 value
Alarm: 20x normal dust level = limit 2 value
Switching contact and LED:
Switching contact ON/OFF
Signal
LED
Operation
contact 1+2 OFF
power OFF or failure
OFF
power OFF
contact 2 ON (allein)
signal < limit 1
green
normal
contact 1 ON (allein)
limit 1 < signal < limit 2
yellow
alert
contact +2 ON
signal > limit 2
red
alarm

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7 Auto-SETUP
To be able to detect variations in the dust flow and to set the alarm if there is excessive dust flow, you must
determine the typical dust flow of the application when the process is operating normally.
The unit has an auto-SETUP function which sets the parameters such that the switching contacts give the
alert when the dust concentration exceeds 5x the normal dust level and an alarm when 20x normal dust level
is exceeded.
(See table on page 9)
For the auto-SETUP you need to know that the process is running with a normal dust flow rate.
Then open the cover of the unit and initiate auto-SETUP by pressing the small white button.
The green LED indicator in the front cover starts lightening when auto-SETUP procedure is executed
successfully.
Auto-SETUP procedure takes 5 minutes to be completed, green LED in the front cover stops blinking and
the Dusty is ready to use.
Fig. 4: Sensor board
Automatic Setup
1. Ensure that the process is in normal conditions.
2. Make sure that the sensor has to be connected to the process and powered for at least 10 minutes in order
to warm up and stabilise.
3. Press the white auto-SETUP button.
4. The green LED in front cover has to blink.
5. Close the enclosure cover and wait for 5 minutes until the green LED lightens indicating the auto-Setup
to be finished.
6. The Dusty is ready to use.

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8 Maintenance
The Dusty needs very little maintenance.
For the maintenance the unit has to be removed from the process so that the sensor probe and the sensor
insulation (white sleeve) can be cleaned.
Hereby it’s possible to prevent deposit bridges between the sensor rod and the duct wall which could induce
to a function failure or short-circuit.
If particles in the gas are sticky and tend to build up, the cleaning needs to be done more often.
Inside the enclosure maintenance is not needed.
9 Troubleshooting
9.1 No switching of the output signals
1. Check the power and the connection of the contacts.
2. Check if there is power on the LED (LED lightens).
3. Execute the auto-SETUP.
If the sensor is not giving any output signals after the checks 1, 2 and 3, please contact:
Our branch offices OR our distributors OR SWR engineering Messtechnik GmbH.
9.2 No sensor response after the auto-SETUP
1. Check if the normal process is going on and if there were normal operation conditions during the auto-SETUP.
2. Check the power and the connection of the signal wiring.
3. Check if there is no short circuit
•there is no contact between the sensor probe and the duct wall.
•the gas is not condensing (because of build up).
•the dust is not sticky: so there is no build up on the sensor base
which could induce to a bridge between the sensor probe and the duct wall.
EN 071129