UL Requirements
The installation of the Fieldbus Box Modules certified by UL has to meet the following requirements.
Supply voltage
Note
- by a 24 VDC supply voltage, supplied by an isolating source and protected by means of a fuse (in accordance with UL248), rated maximum 4 Amp, or
- by a 24 VDC power source, that has to satisfy NEC class 2.
A NEC class 2 power supply shall not be connected in series or parallel with another (class 2) power source!
Note
Warning
To meet the UL requirements, the Fieldbus Box Modules must not be connected to unlimited power sources!
Networks
Note
Warning
To meet the UL requirements, Fieldbus Box Modules must not be connected to telecommunication networks!
Ambient temperature range
Note
Warning
To meet the UL requirements, Fieldbus Box Modules have to be operated only at an ambient temperature range of 0 to 55°C!
Marking for UL
All Fieldbus Box Modules certified by UL (Underwriters Laboratories) are marked with the following label.
