opto engineering LTDVE1CH-40F, Instruction Manual

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Firmware version 1.10 - Document version 1.06 - eng
LTDVE1CH-40F | INSTRUCTIONS MANUAL
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 flashing 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 output. 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
•
15 W at 40 °C
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.
The maximum permissible controller heatsink temperature is 90 °C. If the heatsink temperature rises
above 90 °C, the controller switches off the output channel. The output channel is 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 light. Take care of the actual converter output voltage when calculating
the generated heat.