Mounting and connecting the HMI device 
  3.3 Connecting the device 
Comfort Panels 
Operating Instructions, 07/2017, A5E36770603-AB 
49 
 
Connecting the power supply 
 
Safe electrical isolation  
For the 24 V DC supply, use only power supply units with safe electrical isolation in 
accordance with IEC 60364-4-41 or HD 384.04.41 (VDE 0100, Part 410), e.g. conforming 
to the SELV/PELV standard.  
The supply voltage must be within the specified voltage range. Otherwise, malfunctions at 
the HMI device cannot be ruled out. 
Applies to non-isolated system configurations:  
Connect the GND 24 V connection from the 24 V power supply output to equipotential 
bonding for uniform reference potential. You should always select a central point of 
termination. 
 
External protective circuit  
An external protective circuit is required for operation with 24 V DC, see section 7 
"Lightning protection and overvoltage protection" in function manual "Designing 
interference-free controllers 
(https://support.industry.siemens.com/cs/ww/en/view/59193566
)". 
The following figure shows the connection between the power supply and the HMI device 
with TP1500 Comfort V2 as an example. 
 
The power supply connector is contained in the accessory kit. The power supply connector is 
designed for cables with a maximum cross-section of 1.5 mm².