OPERATING FEATURES
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1 OPERATING FEATURES
1.1 DESCRIPTION
The PWR-120 is an electrical cabinet housing a 24 Vdc power supply which is used to power
up a varying number of reading devices (depending on the product), along with their relative
accessory devices. See chapter 4 for details.
As shown in the Electrical Diagram in Appendix A, the AC Input Line passes through a
protective thermo-magnetic circuit breaker and connects to the monophase switching power
supply.
The 24 Vdc output power is connected to the output terminal blocks which are protected by
the internal power supply features.
Two output power supply status monitoring signals (DC-OK) are provided to connect to an
optional digital alarm. If for some reason the output voltage is reduced by less than 90% of
nominal) these lines open.
1.2 OUTPUT PROTECTION
The power supply implements an overload protection.
1.2.1 Overload Protection
In the event of sustained output current overloading, overload protection is provided where
overload power is supplied as explained in the examples below:
Example 1: Up to 120% power overload
The overload is supplied for approximately 12 seconds and then is reduced (Voltage and
Current) to about 104% power continuously. In this case output voltage is reduced but remains
above 20 Vdc.
Figure 3
– Overload Protection up to 120%