Siemens SIMATIC S5 1P 243, Operating Instructions & Installation Instructions

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● The cooling air can flow in and out freely.
The full air flow provided by the fan is only achieved if air can freely enter the impeller. A
clearance of at least 1 times the air intake diameter must therefore be provided in the axial
direction.
● Hot discharged air must not be drawn in again.
● If there is no protective canopy, then for vertical types of construction where the air enters
from the top, the air entry openings must be protected against the ingress of foreign bodies
and water.
4.4 Thermal motor protection
Thermal motor protection by directly monitoring the winding temperature is permissible if this
is certified and stamped on the rating plate. The temperature sensors used must comply with
DIN 44081/44082 .
PTC thermistors as sole protection guarantee explosion protection in conjunction with function
tested tripping devices with type of protection marking II (2) G. No voltage > 2.5 V may be
applied for any continuity test required on the temperature sensor.
For each speed range of pole-changing motors, use only isolated, interlocked protective
devices that have been tested and certified by an approved test center.
4.5 Interlock circuit for anti-condensation heating
If the anti-condensation heating is operated while the machine is running, this can increase
the temperatures inside the machine.
● Install an interlock circuit that switches off the anti-condensation heating once the main
machine is switched on.
● Only operate anti-condensation heating when the machine is switched off.
4.6 Interlock circuit for the external fan motor
For machines with external fans, install an interlock circuit that prevents the main machine
being switched on if the external fan is not operational.
Preparations for use
4.6 Interlock circuit for the external fan motor
LOHER CHEMSTAR 1PS5
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Operating Instructions 03/2014