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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
The frequency, or period, at which the Automatic Balance Cycle will initiate must also be
set by the user. The permitted settings fir this parameter are as follows:
ABC Frequency
SW3-1 SW3-2 SW3-3 SW3-4 SW3-5 SW3-6 SW3-7
30 minutes
ON
OFF
OFF
OFF
OFF
OFF
OFF
1 hour
OFF
ON
OFF
OFF
OFF
OFF
OFF
2 hours
OFF
OFF
ON
OFF
OFF
OFF
OFF
4 hours
OFF
OFF
OFF
ON
OFF
OFF
OFF
8 hours
OFF
OFF
OFF
OFF
ON
OFF
OFF
16 hours
OFF
OFF
OFF
OFF
OFF
ON
OFF
32 hours
OFF
OFF
OFF
OFF
OFF
OFF
ON
On Request
OFF
OFF
OFF
OFF
OFF
OFF
OFF
Note that only one switch may be in the ON position at any time.
2.8
Automatic Balance Compensation On Request
If the instrument is being used for calibration applications or in system configurations
where the dewpoint measurement cannot be interrupted, it is recommended that the
automatic balance compensation is set to ON REQUEST using SW3 as shown in the
section 2.7 above. Operation of the balance system in the ON RERQUEST mode allows
the user to manually initiate a balance cycle instead if allowing the instrument to perform
this task at set time intervals. The process of balancing the optics system to compensate
for any increase in contamination is still performed automatically. If operating in this
mode, it becomes the responsibility of the user to perform ABC cycles at suitable periods.
When operating in On Request mode, the Balance Cycle can be initiated in any of three
ways:
a)
manually by pressing the front panel switch INITIATE,
b)
by use of the remote input on the rear of the monitor,
c)
by use of the RS-232 interface.
2.9
Data Hold
The data-hold capability allows the measured dewpoint temperature to be temporarily
held during and after an ABC cycle. The measured dewpoint at the moment the balance
cycle starts is maintained for a time period defined by the user. This time period allows
the balance cycle to be completed and the measured dewpoint to settle before returning
to normal measurement mode. This function holds the display, analog output and digital
output for the defined time period, and is activated whenever a Balance cycle is initiated,
i.e. whether manually or automatically.