Pilz PSS67 F 16DI SB-T - Manual (Page 23)

Operating Manual: PSS67 F 16DI SB-T 6-1
Supply Voltage
Please note the following:
• When selecting the power supply, please refer to the requirements stated
under “Technical Details”.
• Overvoltage or interference voltage can damage or even destroy the
electronics on the PSS67 F 16DI SB-T. If this occurs, the affected I/O-
Groups will switch to a STOP condition and all the outputs in the affected
groups will be switched off. You should therefore take note of the relevant
EMC measures.
• WARNING!
Safe electrical isolation must be ensured for the external 24 V supply.
Failure to do so could result in electric shock. Power supplies must
conform to EN 60950, section 2.3, EN 60742 or EN 50178.
• To achieve the lowest possible residual ripple, we recommend that you
install a three-phase bridge rectifier or regulated supply.
• The “Ground” connection to the earth bar or earth fault monitor must be in
accordance with the relevant national regulations (e.g. EN 60204-1,
NFPA 79:17-7, NEC: Article 250).
INFORMATION
The module’s output circuits have been designed to guarantee maximum
safety. To achieve this, extensive tests are carried out internally.
Momentary interruptions to the “Supply” voltage during a test procedure
can falsify the test result, causing the following malfunction:
If the “Supply” voltage is interrupted momentarily, the unbuffered test pulse
outputs will transmit a “0” signal. The buffered module electronics reads
this signal at the pulsed inputs, thereby triggering the user's programmed
reaction. Example: The system reacts as though an E-STOP button has
been operated, although this is not the case: there has been a supply
interruption.
Remedy: “Supply” must be buffered.