Additional Installation Tips
1. Use an EMC cable gland or regular plastic cable gland, remove the outer jacket
and connect the shield to the installation plate with a 360° metal cable clamp.
2. Place the 24 V DC and communications cabling in one cable trunk/cable duct
and 230/380 V AC in another. If the cables need to be crossed, cross them at
90° only. Avoid combining the cabling for stronger 24 V DC outputs with
the communication cabling.
Ferrite cores that are snapped onto the shielded cabling may remove minor
disturbances. Large ferrite pieces that are snapped onto unshielded cabling and
where the wires go 2-4 times around the cores are approximately 5-25 times more
efficient.
7.4 Ambient Temperature
The maximum ambient temperature for the operator panel is provided in the
specifications. The ambient temperature refers to the temperature in the device
cabinet which cools the operator panel’s electronics.
Operator
panel
Power
Power
Power
30 °C outside
Top
50 °C inside
Bottom
40 °C inside
Middle
45 °C inside
Airflow
Axial fan
120 x 120 mm
In most cases, the ambient temperature for the operator panel is significantly
higher than the device cabinet’s ambient temperature.
If the cabinet is tall and there are a number of heat-generating devices, the
temperature at the top of the cabinet is considerably higher than the temperature
increase that would be expected. All electronics are sensitive to heat. The lifespan
of an electrolytic capacitor is cut in half with an 8-10 °C increase in temperature. A
15-20 °C temperature increase results in a quarter of the lifespan etc.
Rittal has a good program for estimating the anticipated average temperature in
the cabinet as well as a large program for controlling the temperature in the device
cabinet.
An enamel-coated steel cabinet has a radiant heat value of 5.5 W/m
2
per degrees C.
Installing a fan inside the cabinet evens out the temperature, while moving air
provides considerably better cooling than still air.
Install the fan so that it sits in a cooler area and blows cold air against the operator
panel. If the fan is mounted at the top and sucks warm air upwards, the ambient
temperature of the fan becomes higher, resulting in a shorter lifespan.
Beijer Electronics, MAEN228
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