opto engineering LTDVE2CH-20F User manual

V 1.03 - eng
ACCESSORIES
INSTRUCTIONS MANUAL
Strobe controller 2 CH
LTDVE2CH-20F

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INDEX
1. Disclaimer ................................................................................................ 5
2. Safety notes ............................................................................................. 5
3. Product end-of-life handling ................................................................... 5
4. General description ................................................................................. 6
4.1. Benefits of current control .........................................................................................6
4.2. Operating mode.........................................................................................................6
5. Getting started ......................................................................................... 7
6. Mechanical fixing..................................................................................... 7
7. Heat dissipation ....................................................................................... 7
7.1. Calculating generated heat per channel....................................................................8
7.2. Reducing generated heat ..........................................................................................8
8. Connections............................................................................................. 8
8.1. Layout of connectors.................................................................................................9
8.2. Power and logic supply ...........................................................................................10
8.3. Light outputs............................................................................................................10
8.4. Input/output synchronization ...................................................................................11
8.4.1. Synchronization inputs.....................................................................................................11
8.4.2. Synchronization outputs...................................................................................................12
8.4.3. Serial RS485 interface .....................................................................................................13
8.4.4. External temperature sensor.............................................................................................13
8.5. Cable size and length..............................................................................................14
9. Communication interfaces.................................................................... 14
9.1. Serial RS485 interface ............................................................................................15
9.2. Ethernet interface....................................................................................................15
10. Visual indicators .................................................................................. 16
11. INIT button functions ........................................................................... 16
12. Pulse shaping logic ............................................................................. 17
12.1. Diagram of internal logic........................................................................................17
12.2. Input filters.............................................................................................................17
12.3. Input multiplexers ..................................................................................................18
12.4. Pulse generator.....................................................................................................19
12.5. Output multiplexers ...............................................................................................19
12.6. Output protection...................................................................................................19
12.7. Free running oscillator...........................................................................................21

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13. Wiring diagrams................................................................................... 21
13.1. Wiring example #1: controller triggers camera ......................................................21
13.2. Wiring example #2: camera triggers controller ......................................................22
14. Operation.............................................................................................. 22
14.1. Operation with Modbus .........................................................................................22
14.1.1. Comparison of Modbus/RTU, Modbus/TCP and Modbus/UDP ...................................23
14.1.2. Supported function codes...............................................................................................23
14.1.3. Read Holding Registers (0x03)......................................................................................23
14.1.4. Write Single Register (0x06)..........................................................................................24
14.1.5. Write Multiple Registers (0x10) ....................................................................................24
14.2. Register file ...........................................................................................................24
14.2.1. Register DEVICE_TYPE...............................................................................................38
14.2.2. Register BOOT_VERSION ...........................................................................................38
14.2.3. Register MCU_VERSION.............................................................................................38
14.2.4. Register FPGA_VERSION............................................................................................38
14.2.5. Register BOARD_VERSION ........................................................................................38
14.2.6. Register OSC_PERIOD .................................................................................................38
14.2.7. Registers FILTER_SEL[0:1]..........................................................................................38
14.2.8. Registers INPUT_SEL[0:3] ...........................................................................................39
14.2.9. Registers GEN_DELAY_BASE[0:3] ............................................................................39
14.2.10. Registers GEN_DELAY_COUNT[0:3].......................................................................40
14.2.11. Registers GEN_WIDTH_BASE[0:3] ..........................................................................40
14.2.12. Registers GEN_WIDTH_COUNT[0:3].......................................................................40
14.2.13. Registers OUTPUT_SEL_HI[0:1] and OUTPUT_SEL_HI[8:9] ................................41
14.2.14. Registers OUTPUT_SEL_LO[0:1] and OUTPUT_SEL_LO[8:9] ..............................41
14.2.15. Registers PRT_CNT_ON[0:1] .....................................................................................42
14.2.16. Registers PRT_ENA_ON[0:1].....................................................................................42
14.2.17. Registers PRT_CNT_OFF[0:1]....................................................................................42
14.2.18. Registers PRT_ENA_OFF[0:1] ...................................................................................42
14.2.19. Registers CUR_RANGE[0:1] ......................................................................................43
14.2.20. Registers CUR_VALUE[0:1].......................................................................................43
14.2.21. Register RS485_MODBUS_ADDR ............................................................................43
14.2.22. Register RS485_LINE_SPEED ...................................................................................43
14.2.23. Register RS485_LINE_PARITY .................................................................................44
14.2.24. Registers ETH_MAC_ADDR[0:2]..............................................................................44
14.2.25. Registers ETH_HOSTNAME[0:7] ..............................................................................44
14.2.26. Register ETH_DHCP_ENABLE .................................................................................45

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14.2.27. Register ETH_IP_ADDR_HI ......................................................................................45
14.2.28. Register ETH_IP_ADDR_LO .....................................................................................45
14.2.29. Register ETH_SUBNET_MASK_HI ..........................................................................45
14.2.30. Register ETH_SUBNET_MASK_LO .........................................................................45
14.2.31. Register ETH_DEF_GATEWAY_HI...........................................................................45
14.2.32. Register ETH_DEF_GATEWAY_LO..........................................................................45
14.2.33. Register ETH_PRI_DNS_HI .......................................................................................46
14.2.34. Register ETH_PRI_DNS_LO ......................................................................................46
14.2.35. Register ETH_SEC_DNS_HI ......................................................................................46
14.2.36. Register ETH_SEC_DNS_LO.....................................................................................46
14.2.37. Register ETH_MODBUS_ADDR ...............................................................................46
14.2.38. Register ETH_MODBUS_TCP_PORT .......................................................................46
14.2.39. Register ETH_MODBUS_UDP_PORT ......................................................................46
14.2.40. Registers WEB_PASSWORD[0:3]..............................................................................47
14.2.41. Register CONVERTER_TEMPERATURE.................................................................47
14.2.42. Register DRIVER_TEMPERATURE..........................................................................47
14.2.43. Registers REMOTE_TEMPERATURE[0:1]...............................................................47
14.2.44. Register SUPPLY_VOLTAGE.....................................................................................47
14.2.45. Registers MEASURED_CURRENT[0:1] ...................................................................48
14.2.46. Registers MEASURED_VOLTAGE[0:1]....................................................................48
14.2.47. Register ERROR_WORD............................................................................................48
14.2.48. Registers GEN_HOLD_BASE[0:3] ............................................................................49
14.2.49. Registers GEN_HOLD_COUNT[0:3].........................................................................49
14.2.50. Registers GEN_EDGE_SEL[0:3] ................................................................................49
14.2.51. Registers DRIVE_TIME[0:1] ......................................................................................50
14.2.52. Registers CUR_RED_DELAY[0:1].............................................................................50
14.2.53. Registers CUR_RED_VALUE[0:1].............................................................................50
14.2.54. Register SOFTWARE_TRIGGER...............................................................................51
14.2.55. Register CONVERTER_MODE..................................................................................51
14.2.56. Register CONVERTER_MAXIMUM_VOLTAGE.....................................................51
14.2.57. Register CONVERTER_PRESET_VOLTAGE...........................................................52
14.2.58. Register DRIVER_MODE...........................................................................................52
14.2.59. Register DIGIPOT_VALUE ........................................................................................52
14.2.60. Register CONVERTER_VOLTAGE ...........................................................................52
14.2.61. Register DRIVER_VOLTAGE ....................................................................................53
14.2.62. Register SUPPLY_CURRENT ....................................................................................53
14.2.63. Register CONVERTER_CURRENT...........................................................................53

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14.2.64. Registers CAL_XXX ...................................................................................................53
14.2.65. Register CAL_UNLOCK_CODE[0:1] ........................................................................53
14.2.66. Register BOARD_COMMAND ..................................................................................53
14.3. Operation with a web browser...............................................................................54
14.3.1. Main page and navigation menu ....................................................................................54
14.3.2. Setup synch inputs TR1-TR2.........................................................................................56
14.3.3. Setup pulse generators GN1-GN4..................................................................................57
14.3.4. Setup light outputs LD1-LD2 ........................................................................................59
14.3.5. Setup synch outputs SH1-SH2.......................................................................................61
14.3.6. General setup..................................................................................................................61
14.3.7. Advanced setup ..............................................................................................................63
15. Operation with FabImage .................................................................... 64
15.1. Filter selection .......................................................................................................65
15.2. Designing a simple program for reading a register................................................67
15.3. Designing a simple program for writing a register .................................................68
16. Electromagnetic compatibility ............................................................ 70
17. Firmware update procedure................................................................ 70

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1. Disclaimer
Always deploy and store Opto Engineering products in the prescribed conditions in order to ensure
proper functioning. Failing to comply with the following conditions may shorten the product lifetime
and/or result in malfunctioning, performance degradation or failure.
Ensure that incorrect functioning of this equipment cannot cause any dangerous situation or
significant financial loss to occur. It is essential that the user ensures that the operation of the
controller is suitable for their application. All trademarks mentioned herein belong to their respective
owners.
Except as prohibited by law:
•All hardware, software and documentation are provided on an “as is” basis
•Opto Engineering accepts no liability for consequential loss, of any kind
Upon receiving your Opto Engineering product, visually examine the product for any damage during
shipping. If the product is damaged upon receipt, please notify Opto Engineering immediately.
2. Safety notes
Please read the following notes before using this controller. Contact your distributor or dealer for any
doubts or further advice.
This device must not be used in an application where its failure could cause a hazard to human
health or damage to other equipment. Keep in mind that if the device is used in a manner not
foreseen by the manufacturer, the protection provided by its circuits and by its enclosure may be
impaired.
This is a low voltage device. As such, the potential difference between any combination of applied
signals must not exceed, at all times, the supply voltage. Higher voltages may cause a fault and can
be dangerous to human health.
This device has limited protection against transients caused by inductive loads. If necessary, use
external protection devices like fast diodes or, better, specific transient protectors.
The controller outputs pulses with high energy content. The user must be careful to connect the
inputs and outputs correctly and to protect the output wiring and load from unintentional short-
circuits. When the device is switched off, there is still energy stored in the internal capacitors for at
least five minutes.
When operating the controller at the maximum ratings it can get very hot. The controller should be
positioned where personnel cannot accidentally touch it and away from flammable materials. Never
exceed the power ratings stated in the manual.
3. Product end-of-life handling
Observe the following guidelines when recycling this equipment or its components.
Production of this equipment required the extraction and use of natural resources. The equipment
may contain substances that could be harmful to the environment or human health if improperly
handled at the product’s end of life. In order to avoid release of such substances into the environment
and to reduce the use of natural resources, we encourage you to recycle this product in an
appropriate system that will ensure that most of the materials are reused or recycled appropriately.
This symbol indicates that this product complies with the applicable European Union
requirements according to the WEEE (Waste Electrical and Electronic Equipment)
Directive 2012/19/EU

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4. General description
Any machine vision application employs some kind of light controller. Light controllers are widely
used to both optimize illumination intensity and obtain repeatable trigger sequencing between lights
and vision cameras.
This controller is a compact unit that includes power supply conditioning, intensity control, timing
generation and advanced triggering functions.
The controller can be set up using a PC with serial RS485 or Ethernet interfaces. Configurations are
saved in non-volatile memory so that the controller will resume operation after a power cycle.
4.1. Benefits of current control
Most LED manufacturers suggest their products to be driven using a constant current source, not a
constant voltage source. This is because, using a constant voltage driving, small variations in
temperature or voltage at the LEDs can cause a noticeable change in their brightness.
Brightness control with voltage is also very difficult because of the non-linearity of brightness with
voltage. On the contrary, the brightness is approximately linear with current, so by driving the LEDs
with a known current, intensity control is linear.
4.2. Operating mode
This strobe controller has two programmable, current-controlled light outputs. The two light outputs
can be used in pulsed or continuous mode.
In pulsed mode the light is switched on only when necessary. A digital input is used as a trigger
source. When a rising or falling edge on the trigger signal is detected the output is pulsed for the
programmed amount of time.
Using this technique, it is possible to obtain excellent steady images of moving objects. The camera
can be set for an arbitrary long exposure time and the light turned on for a shorter time, just enough
to freeze the motion. This helps to overcome the uncertainty issues usually related with integration
start which, to some degree, afflict most commercial cameras.
The delay from the trigger to the output pulse, the width of the output pulse and the intensity of the
output pulse are all independently configurable. The pulse delay can range from 0 µs to 1 s. The
pulse width can range from 1 µs to 1 s.
In continuous mode the light is always switched on, independently from the trigger signal. Using this
technique, the maximum current value for each channel has to be limited in order to prevent the
overheating of the controller.
The two output drivers in the controller can either operate in two modes: independent mode and
shared mode. In independent mode, the two light outputs are completely autonomous and currents
and timings are independent.
In the shared mode the two output drivers are interconnected. This results in twice the maximum
output current than in the independent mode. In the shared mode, the controller effectively behaves
as a single channel controller.
In either independent mode or shared mode there are two current ranges. In independent mode the
current ranges are:
Low current, up to 250 mA (with a resolution of 1 mA)
High current, up to 20 A (with a resolution of 20 mA)
In shared mode the current ranges are:
Low current, up to 500 mA (with a resolution of 2 mA)

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High current, up to 40 A (with a resolution of 40 mA)
The controller must be powered with a fixed supply voltage of 24 V. There is an internal DC/DC
converter that can be programmed to provide any voltage between 5 V and 190 V for supplying the
output drivers. This allows a large number of different lights to be efficiently driven.
The DC/DC converter is power limited to around 60 W. Limit maximum continuous current per
channel to:
2 A at a maximum voltage of 15 V
1 A at a maximum voltage of 30 V
In any case, if any of the lights is driven continuously limit the DC/DC converter output voltage to a
maximum value of 55 V.
For more information about current and power limitations refer to chapter 7.
5. Getting started
Carefully read the sections on Safety Notes and Heat Dissipation and check the product fits your
needs. Mount the controller as described in the section on Mechanical fixing.
Connect the controller as in the section on Connections. When the controller powers up it should
show the PWR LED lit with a stable green colour and the RUN LED lit with a pulsing green colour.
Read the section on Operation. The controller can be configured by using both a serial RS485
interface and an Ethernet interface (see chapter 9).
6. Mechanical fixing
The controller must be mounted on a suitable thermally conductive surface in order to dissipate the
generated heat. Allow free flow of air around the unit. The controller has an IP rating of 20 and should
be installed so that moisture and dirt cannot enter it.
An enclosure may also be required for other parts of the system such as power supplies. That
enclosure would provide both mechanical and environmental protection in industrial applications.
7. Heat dissipation
The controller integrates several linear circuits to produce the constant current outputs. This means
that it generates heat which needs to be dissipated. The operating temperature range is 0 °C to
40 °C.
With a suitable heatsink the controller can approximately dissipate the following average powers:
20 W at 25 °C (about 10 W per channel)
15 W at 40 °C (about 7.5 W per channel)
A simple way to estimate the maximum average power the controller can dissipate is by applying the
following formula:
DissipablePower [W] = (TempHeatsink [°C] – TempAmbient [°C]) / ThResistance [°C/W]
Where:
DissipablePower is the maximum average power the controller can dissipate
TempHeatsink is the maximum temperature of the controller heatsink
TempAmbient is the actual temperature of the ambient where the controller is placed
ThResistance is the thermal resistance between the heatsink and the ambient
For this controller the ThResistance parameter is about 3.2 °C/W.

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The maximum permissible controller heatsink temperature is 90 °C. If the heatsink temperature rises
above 90 °C, the controller switches off all the output channels. Output channels are then reactivated
once temperature falls below 80 °C.
If the average power that must be dissipated is greater than the previously stated value, a different
and more efficient cooling system is required. Solutions could be the use of a cooling fan (active
cooling system) or the use of a bigger heatsink (passive cooling system).
There is an internal DC/DC converter that can be programmed to provide any voltage between 5 V
and 190 V for supplying the lights. Take care of the actual converter output voltage when calculating
the generated heat.
7.1. Calculating generated heat per channel
For a pulsed output, the average power that is transformed to heat and then must be dissipated can
be calculated using the following formula:
Heat [W] = LightCurrent [A] * (DriverVoltage [V] – LightVoltage [V]) * DutyCycle [·]
Where:
LightCurrent is the illuminator operating current
LightVoltage is the illuminator operating voltage
DriverVoltage is the actual DC/DC converter output voltage (from 5 V to 190 V)
DutyCycle is the actual duty cycle
The duty cycle is given by:
DutyCycle [·] = PulseWidth [s] * TriggerFrequency [Hz]
If the output is driven in continuous mode, the previous equations are still valid but the parameter
DutyCycle becomes 1.0 because the output is always active. In continuous mode limit the output
current to 2 A at a maximum voltage of 15 V and to 1 A at a maximum voltage of 30 V.
The parameters LightCurrent and LightVoltage are light specific and should be either given in the
light documentation or measured experimentally.
7.2. Reducing generated heat
The total heat generated by the controller is simply given by adding the generated heat for each of
the two channels, as calculated in the previous section.
There are several ways to reduce the heat generated by the controller. The simplest way would be
to turn the light off when not needed. If the light is on only when necessary the generated heat can
be drastically diminished. Another opportunity would be to reduce pulse width or output current, if
permitted by the application.
Another strategy to reduce the generated heat would be to connect lights in series instead of parallel,
if possible. If you have several lights connected in parallel then changing the arrangement to series
will increase the voltage across them but also reduce the overall current.
The last option, feasible with this two channels controller, would be to use two or more controllers
and use just a few channels from each. For high power applications this may be the only solution.
8. Connections
See the next sections for information about connections. Power supply and light output connections
are made via screw terminals on the right side panel of the controller. Check all connections carefully
before switching on the equipment.
The controller has two 24 V supplies for the power and logic sections. This is to increase versatility.

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Supply to the logic section should always be present, while supply to the power stages can be cut
off at any time. Supply to the power stages can be removed to protect the end user from photo-
biological hazard and other dangerous situations that may happen during fault conditions.
These two supplies can be connected together if convenient. For convenience, they share a common
negative terminal.
8.1. Layout of connectors
The drawing in Figure 1: connectors on the controller depicts all the controller connections, which
are easily accessible on the left side and right side panels. As indicated in the drawing, connectors
are identified by their unique designators (P1, P2, P3, P4 and P5).
Figure 1: connectors on the controller
The connectors are briefly described below. A detailed description follows in the next sections.
Connector P1 is used to supply power
Connector P2 is used to connect the two lights
Connector P3 is an Ethernet RJ45 jack
Connector P4 is a USB port (B type), not active at the moment
Connector P5 is used for input/output synchronization and for serial RS485 communication
For connectors P1, P2 and P5 a mating plug is provided in the controller package. For convenience
the relevant manufacturer part numbers are listed in Table 1: mating plugs for the controller
connectors. Even if equivalent mating plugs may be available, these are the recommended
components.
Connector designator
Manufacturer
Mating plug part number