Siemens TRAFFIC CONTROLS TC12 Manual De Usuario

 

TC12 Installation, Commissioning & Maintenance Handbook 

LEDs are provided on the front edge of the Modem Board and PSU Board to 
p

rmation

s and their functions 

are shown in Figure 16. 
 

A power LEDs on the modem P
 

quest to send. In normal working this means that the control signal is being 

 the line. All yellow 

off at 

 come on once for every OTU which 

plies on the line during the second (the LED is set by the modem carrier detect 

output and does not indicate that the carrier detected was a valid reply message). 

o LEDs will illuminate on SIP 

anel if the PC has no power. 

 

ard is OK (5 V supply from PSU PCB). 

The second LED on the digital output PCB indicates a watchdog fail. If this occurs 

rovide basic status info

. The position of these LED

ll 

CB should be ON. 

The yellow transmit LEDs indicate that the particular modem has received a 
re
transmitted on the line. However if switches/cables have been set up incorrectly 
the LED may be ON, without the control signal actually reaching
LEDs on all modem PCBs should go on together (though not necessarily go 
the same time) once per second. 
 
The green receive LED (Carrier detect) should
re

 

The PC power LED on the PSU PCB should be ON. IF it is OFF then there is a 
fault, however no audible alarms will sound and n
p

The Digital output PCB has two status LEDs. The top LED indicates that the 
Power to the bo
 

all digital outputs are switched off on that board. 
 

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