Universal Robots ur3 - 5.2 LED Indicators and Fuses on Safety Control Board

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5.2 LED indicators and Fuses on Safety Control Board
Safety Control Board (SCB)
The 5 A fuse “48 V” protects all 48 V for over current in the system inclusive Euromap.
This information is only for troubleshooting. Do NOT replace the fuse on any circumstances.
Do ONLY replace the SCB with a new tested board.
Fuse 24 V: 2 fuses 5 Amp in parallel for the DI/DO 24 V supply on the safety control board
no matter if the 24 V is from the controller or external power supply.
LED indicators:
 12V-PSU On when the power plug is connected.
 12V System: On when the power on has been activated
 5V On when “12 V System” is on and indicate that 5 V is ok.
 -4V On when “12 V System” is on and indicate that - 4 V to analog I/O is ok.
 3V3A On when 5V is on and indicate 3.3 V for logic Safety circuit A
 3V3B On when 5V is on and indicate 3.3 V for logic Safety circuit B
 48V 48 V is present on the safety control board
 24V 48 V is detected and ok, indicate that internal 24 V is present for I/O’s
 R 48 V on robot arm
 A Status for Logic A: a blink sequence
 B Status for Logic B: a blink sequence
LED