Keithley 2701, Service Manual

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3-8 Routine Maintenance Model 2701 Service Manual
Resetting relay closure count
NOTE
The Model 2701 must be in the manufacturing calibration mode to reset the closure
count. To do so, press and hold the OPEN key while turning on the power, then send
the :CAL:PROT:CODE “code” to unlock calibration (default code: KI002701).
After resetting relay counts, send :CAL:PROT:LOCK to lock out calibration.
To reset the relay closure count of specific channels to 0, send this command via remote:
:ROUTe:CLOSe:RCOunt (@clist)
Again clist is the summary of channels to be reset. For example, the following command
resets channels 2 and 7 of a module in slot 1 to 0:
:ROUT:CLOS:RCO (@102,107)
The following command resets the count of slot 1 module channels 1 through 10:
:ROUT:CLOS:RCO (@101:110)
Setting count update interval
Relay closure counts are updated in temporary RAM every time a channel is closed
regardless of how it was closed: by a SCPI command, front panel control, or during a scan.
These counts are permanently written to the EEPROM on the card only at a user-settable time
interval (which has a factory default of 15 minutes) or whenever the counts are queried. Valid
intervals (set in integer number of minutes) are between 1 and 1440 minutes (24 hrs). Relay
closures are counted only when a relay cycles from open to closed state. If you send multiple
close commands to the same channel without sending an open command, only the first closure
will be counted.
The lower the interval, the less chance there is of losing relay counts due to power failures.
However, writing to the EEPROM more often may reduce scanning throughput. The higher the
interval, the less scanning throughput is reduced, but more relay counts may be lost in the event
of a power failure.
To set the count update interval, send this command:
:ROUTe:CLOSe:COUNt:INTerval <interval>
For example, to set the interval to 30 minutes, send this command:
:ROUT:CLOS:COUN:INT 30