Error Conditions - Keithley 7090 Instruction Manual

3-8 Operation

Error conditions

Refer to the Model 7001 or Model 7002 User Manual for details of Model 7001/7002
front panel reported errors.
For some errors contingent on user actions, the Model 7090 provides one red LED located
at the back of the card to indicate certain error conditions, which are summarized in
Table
Table 3-1
Error conditions
LED Status
On continuously
Blinks at ~ 2Hz rate
3-1.
Cause
The switch module has an internal
hardware malfunction.
User error. The 7090 received a
close operation to close more than
one channel.Under these circum-
stances, it is not clear which single
channel should have been closed.
For laser safety reasons, the 7090
resets to avoid a potential open
beam condition.
NOTE
7001/2 front panel will
still show conflicting
channels as closed.
Model 7090 Instruction Manual
Resolution
7090 must be returned to the factory to be
serviced.
Most likely, the 7001/2 system was not pro-
grammed for single channel mode when it
should have been. Or, there is an error in the
scan list or channel list. Refer to 7001 Manual
for card programming details. This error
clears after the next valid command is given
such as an OPEN ALL for reset.