Ahlborn ALMEMO 2590-2A Operating Instructions Manual page 49

Sleep : Internal cycle only, automatically switching off for long-term moni-
toring
Monitor : Internal cycle, not disturbed by computer scanning activity
Fail-safe : Cyclic scanning by the PC; after any failure, internal cycle re-
sumes
Scanning mode function :
Set scanning mode by pressing :
Sleep mode
For long-term monitoring involving large measuring cycles the device can also be
operated in sleep mode. In energy-saving sleep mode the measuring instrument
is completely switched off after each measuring point scan (please note when
using sensors with own power supply) and switched on again automatically after
the cycle expires ready for the next measuring point scan. In this way with just
one set of batteries or one battery recharge up to 15000 measuring point scans
can be performed; for a cycle lasting 10 minutes this represents a measuring ca-
pability of over 100 days.
With the selection of the Sleep mode after confirmation of a query

display all necessary parameters are possibly configured!
For data recording in sleep mode please perform the following steps :
1. Enter a cycle lasting at least 2 minutes
2. Activate saving in this cycle :
3. Select scan mode :
4. Sleep mode program (see 9.5):
5. In the menu
The device should then display
It should then switch off again and as verification the LED ´SLEEP´ (4) flashes.
Only the red lamp ´SLEEP´ at the top of the window flashes rhythmically.
6. In the specified cycle the instrument switches
on automatically, performs one measuring point
scan, and then switches off again.
7. To quit sleep mode press
8. To cancel the measuring operation press
A measuring operation can be started in sleep mode using the start

time (see 12.5.9); however, in sleep mode it cannot be stopped using
the end time and measuring duration.
Monitor mode:
If a data logger being operated on a cyclic basis is to be monitored occasionally
by computer the new ´monitor mode´ should be used. Internal cyclic scanning
is not influenced in any way by software scanning; (in Win-Control ´safe initiali-
zation´ must be deactivated).
The internal cycle is started with the software start; it may also have been started
previously. Scanning by the internal cycle outputs no data to the interface. To
accept data the memory must have been activated.
start measuring operation by pressing :
Data logger
Mode : Normal
<SET>
Cycle : 00:05:00 S
Saving to memory :
Saving to memory :
.
Sleep On
<STOP>
<STOP>
12. Function menus
Mode:Normal
Mode::Normal
Sleep
<START>
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