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MA1044 MAQ20-RTD31/-RTD41 Hardware User Manual
Page 8 of 38
7.0 LED Indicators
A set of 5 LEDs on the top panel of the MAQ20 I/O modules indicate module power, operation,
communication, and alarm status.
Figure 8: LED Indicators
LED Function and Troubleshooting Tips:
PWR
Normal operation: BLUE, solid lit
LED Off: Abnormal power situation
▪
Verify that a MAQ20-COMx is present in system
▪
Verify that the MAQ20-COMx module has 7-34VDC power connected and turned on
▪
Determine if the module is communicating by observing the TX and RX LEDs
STAT
Normal operation: GREEN, 1 Hz blinking
Module Detect: A write to the Module Detect Register will force this LED to blink at 5Hz rate for 5
seconds so the module location in a system can be visually identified. Referring to
the Address Map, this module register is at address 98, offset from the module
base address.
LED Constant On or Constant Off: Abnormal operation
▪
Remove and reinstall module to force a reset
▪
Remove and reinstall module into another backbone position
▪
Determine if the module is communicating by observing the TX and RX LEDs
RX, TX
Normal Operation
– YELLOW, rapid blinking during communication with MAQ20-COMx module
LED Constant Off: Abnormal operation or no communications to MAQ20-COMx module
▪
Verify communications by sending a request for data. Note that the fast communications rate
used on the system backbone will result in the LED appearing dim due to short blinking cycle
▪
Verify that the PWR and STAT LED indicate normal operation
▪
Verify that there is only one MAQ20-COMx module installed in the system