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MA1044 MAQ20-RTD31/-RTD41 Hardware User Manual
Page 12 of 38
10.0 Maintaining a System
The MAQ20-COMx Communications Module periodically scans the system and will detect if a
MAQ20 I/O module has been removed from the system or has lost communications. When this
happens the module Registration Number will be released and available for reassignment.
Standard system maintenance involves a simple three step process:
STANDARD MAINTENANCE PROCESS
1.) Turn system power on and observe communications activity on the I/O modules.
2.) CASE 1: I/O module is replaced with one having a different model number or serial number
Remove a single MAQ20 I/O module from any local or remote backbone position. Replace the
module with another having a different model number. This module can be installed in any vacant
local or remote backbone position. Observe that the green Power LED is on and that there is
communications activity on the TX and RX LEDs. Allow 1 second for registration.
This module
now has the same Registration Number as the one removed.
CASE 2: I/O module is suspected faulty and is to be replaced with the same model number
Remove a single MAQ20 I/O module from any local or remote backbone position. Replace the
module with another of the same model number. This module can be installed in any vacant local
or remote backbone position. Observe that the green Power LED is on and communications
activity is seen on the TX and RX LEDs. Allow 1 second for registration.
This module now has
the same Registration Number as the one removed.
Label and connect input/output wiring to the I/O module and if desired record physical position in
the system.
3.) Repeat Step 2 for any remaining MAQ20 I/O modules in the system requiring maintenance.
ALTERNATE MAINTENANCE PROCESS
1.) With system power off, remove any I/O modules which are to be replaced. Replace the modules
with others of the same or different model numbers. Modules can be installed in any vacant local
or remote backbone position.
Label and connect input/output wiring to the I/O module and if desired record physical position in
the system.
2.) Apply system power and observe that each module has the green Power LED on and
communications activity is seen on the TX and RX LEDs. Registration is complete when module
TX and RX LEDs all have a repeating blink pattern. Replaced modules have now been assigned
the Registration Numbers of those removed, but in a random sequence not associated with the
physical position on the backbone. Modules which were not replaced retain their assigned
Registration Numbers.
NOTES:
Once the registration process is complete, Registration Numbers are permanent as long as I/O modules are not
removed from or added to a system. When system power is cycled or the system is reset, I/O module
Registration Numbers will always remain the same. Tools within MAQ20-940 ReDAQ Shape Software for
MAQ20 allow the user to reassign and save Registration Numbers. Refer to the
MAQ20 I/O Module Registration
section for further details.
Module Detect: A write to the Module Detect register at I/O module register address 98 plus the module offset
based on Registration Number will blink the STAT LED on the top angled surface of the module at a 5Hz rate
for 5 seconds so the module location in a system can be visually identified.