Reading Relay Closure Count; Setting Count Update Interval - Keithley 2750 User Manual

2-32 Close/Open Switching Module Channels

Reading relay closure count

To determine the closure count of specific channels, send this query via remote:
ROUTe:CLOSe:COUNt? <clist>
Here, <clist> is the summary of channels. For example, to determine the closure count of
channels 1 and 4 of a module in slot 1, the following query would be sent:
ROUT:CLOS:COUN? (@101,104)
The following query would determine the closure count of slot 1 module channels 1
through 10:
ROUT:CLOS:COUN? (@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 an SCPI command, front panel control, or during a
scan. These counts are permanently written to the EEPROM on the card only at a user-set
time interval (which is initially set to 15 minutes at the factory), or whenever the counts
are queried. Valid intervals (set in integer number of minutes) are between 10 and 1440
minutes (24 hrs).
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.
NOTE
To set the count update interval, send this command:
ROUTe:CLOSe:COUNt:INTerval <NRf>
where; <NRf> = 10 to 1440 (minutes)
For example, to set the interval to 30 minutes, send this command:
ROUT:CLOS:COUN:INT 30
If the Model 2750 is turned off before the updated count is written to EEPROM,
the relay counts will be lost. It is good practice to add the ROUT:CLOS:COUN?
<clist> command at the end of a program to manually update the count.
Model 2750 Multimeter/Switch System User's Manual