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KAHN INSTRUMENTS, INC.
885 Wells Road, Wethersfield, CT 06109
Tel: 860-529-8643; Fax: 860-529-1895
E-mail: [email protected]
www.kahn.com
Note that the Data Hold time period starts when the ABC cycle starts. Therefore the Data
Hold duration time should be set to last longer than this period to allow the instrument to
settle on a new measurement, before the data hold function is switched off. This “settling
period” will be different for each application, but generally the drier the gas the longer this
period will be. For example at -50°C dewpoint this settling period may be in the order of
30 minutes, while at +30°C dewpoint the settling period may only be 1 minute.
The time period of the Data Hold Function is set as follows :
Data Hold Duration
SW2-1
1 minute
SW2-2
2 minutes
SW2-3
4 minutes
SW2-4
8 minutes
SW2-5
16 minutes
SW2-6
N/A
SW2-7
N/A
SW2-8
N/A
Note that only one switch may be in the ON position at any time.
Note that to disable the Data Hold, all switches SW2-1 to SW2-5 should be in the OFF
position.
2.10 Clean Optics Warning
After some time in use, when the optics have collected a considerable degree of
contamination, the balance system produces a warning signal demanding that the optics
need to be cleaned. This warning is given by the dual colored ABC STATUS (LED) on
the Series 4000 Monitor front panel which will glow red. If this warning is ignored, the
instrument cannot accurately measure dewpoint.
2.11 Max Cool
This control is a non-latching push button switch, which over-rides the dewpoint control
loop system and applies maximum cooling current to the Peltier. The purpose of this
control is two-fold:
a)
By pressing and holding in the MAX COOL button it is possible to determine
what temperature the mirror can be driven down to with reference to the
sensor body temperature. This temperature will be indicated on the Monitor
Unit digital display.
