AMETEK Lx Series II - Manual (Page 123)

User Manual Lx / Ls Series II
119
7.4 Isolating amplifier failures in multi-box systems
A self test can be performed over the bus by sending the *TST? query command. The self test
will run until the first error is encountered and terminate. The response to the query will either be
the first error encountered or 0 is no error was found. (Selftest passed).
On multi-box model configurations such as 9000Lx/2 or 18000Ls/3, it is possible to isolate
certain failures to a particular chassis. This can be done using the *TST? Self test error codes.
Note: The self test should always be run in 3 phase mode on all Lx models and Ls models with
the
–MODE option. If the self test is run in single phase mode, not all aspects of the Phase 2/B
and 3/C hardware will be tested as a result. If the power source is a Ls-1 single phase only
configuration, the self test can only be run in single phase mode.
To execute a self test, the IEEE-488, RS232C, LAN or USB interface must be used. The LxGui
command line can be used to send the *TST? Command. The following rules apply:
1. If a voltage error is reported on phase 1, 2 or 3, it indicates the corresponding amplifier in
the Master chassis has most likely failed.
2. If a current error is reported on phase 1, 2 or 3, it indicates one of the auxiliary chassis
amplifiers on the phase indicated has failed. On a 2 box configuration, there is only one
auxiliary chassis. On a three box configuration, it is not possible to tell which of the two
auxiliary amps have failed. They could also both have failed in this case.
To further isolate the failed amplifier in a three-box configuration, the outputs of all three chassis
must be disconnected from each other. Then program each phase and close the output relay.
Check the output of each chassis for the expected output voltage. The chassis with not output(s)
will have the failed amplifier.