As required by CEI 64/8, the condition of maximum safety in the opening of the switches is obtained with the use of buttons with normally closed contacts associated to an opening coil at minimum voltage. This solution is critical because any voltage interruption (even short) creates an out of service with the relative consequences.The TCS-A5 device has the benefits to have the command (button, relay,etc.) with normally closed contacts and at the same time those of the shunt trip opening coil (immune from defect of opening on voltage brake) instead of that a minimum voltage. This device, as the TCS classical, control the efficiency of the safety network or the opening circuit of the switch associated.
The classic application of the device is to command a switch with shunt trip opening coil (BA) using a series connection of safety buttons. When the device is connected as showed in the picture, with Vc present but without Vaux, the relays are de-energized, the BA don’t receive energy and the relay RA is in alarm status. When the Vaux is supplied the led ON turn ON, the Alarm Relay (RA) is energized, the device is in condition of normal functioning, the Trip Relay(RT) after 80 ms is energizing, after others 80 ms the Safety Relay (RS) is energizing and the Led Ready turn ON. In this condition the device is ready to receive the command to trip from the normally closed safety button (NC). After 150 ms from the trip request (NC button pressed) the RT relay is de-energized while the BA actuator is energized, opening the associated switch. The trip status is signalled on the device with the TRIP led turnedON and the READY led turned off and with a remote lamp in parallel to the BA coil. This condition can be stored. In this way it’s possible to use safety buttons with instantaneous opening (without mechanical retain).
- Auxiliary power voltage: 115÷230 V c.a.
- Line voltage BA: 110÷230 V c.a./c.c.
- Functioning Voltage NC contacts: max 30 V c.c.
- Current of NC contacts: min 0,4mAcc max 0,7mAcc
- BA command output: 1 contact 5A 250 V c.a. free of voltage (fail safe)
- Alarm output: 1 change 5A 250 V c.a. free of voltage (fail safe)
- Input NC contacts: n°5 monitored + number unlimited and uncontrolled
- Working temperature: -10°C ÷ +60 °C