System Manual Modular Systems  7 Start-Up 
HI 800 191 E Rev. 2.02  Page 49 of 114 
7.1.1.3  Natural Convection 
When the natural convection is used, the lost heat is dissipated through the enclosure walls. 
Requirement: The ambient temperature must be lower that the temperature within the 
enclosure. 
The maximum temperature increase (T)
max
 of all electronic devices within the enclosure is 
calculated as follows: 
                  P
V
 
(
T)
max
 = ——— 
 k • A 
The power dissipation P
V
 can be calculated based on the specifications for the electric power 
rating of the system and its inputs and outputs. 
Example: Calculation of power dissipation P
V
 for the F35 controller 
  Idle current consumption of the controller: 0.75 A at 24 V. 
  8 digital outputs with current consumption of 1 A each at 2 V. 
  The current consumption of the digital, analog and counter inputs can be neglected. 
As a result, the maximum thermal power dissipation is approx. 34 W. 
The temperature within an enclosure can also be calculated in accordance with VDE 0660, Part 
507 (HD 528 S2). 
All considerations about heat must take every component within a cabinet or enclosure into 
account! 
 
 
7.2  Installation and Mounting 
The safety-related HIMatrix controller systems can be installed on mounting surfaces, and also 
in closed enclosures such as control stations, terminal boxes and control cabinets. They have 
been developed in compliance with the relevant standards for EMC, climate and environmental 
requirements.  
The list of the standards that must be observed is specified in Chapter 2.2 and in the manuals 
for the HIMatrix systems. 
The protection class of the HIMatrix systems (IP20) can be increased by installing them in an 
appropriate enclosure in accordance with the requirements. In doing so, appropriate heat 
dissipation must be ensured, see Chapter 7.1. 
Only personnel with knowledge of ESD protective measures may modify or extend the system 
wiring. 
Electrostatic discharge! 
Failure to comply with these instructions can damage the electronic components. 
  Prior to working with HIMA components, touch an earthed object. 
  Make sure that the workspace is free of static and wear an ESD wrist strap. 
  If not used, ensure that the module is protected from electrostatic discharge, e.g., by 
storing it in its packaging. 
7.2.1  Mounting 
The location for installing a HIMatrix F60 subrack must be chosen observing the operating 
requirements (see Chapter 2.2) to ensure a smooth operation.