Ph Span Adjustment; How To Set Date And Time - Martek MARK 22 Operation Manual

5 - CALIBRATION
ZERO
and the "SPAN" prompt will be flashing.

5.3.2 pH Span Adjustment

After the pH sensor has been zeroed, the
span adjustment can be set. Remove the pH
sensor from the pH buffer 7.00 solution and
rinse it with fresh water. Using a light tis-
sue, gently pat the glass bulb of the pH elec-
trode removing observable moisture.
Place the pH sensor in pH buffer 4.00 or
10.00 solution depending upon the pH range
of the solution the sensor is to measure.
Choose the "SPAN" option by pressing the
SELECT key. The display will prompt with
the following message:
PLACE SENSOR IN
HI pH STANDARD
Then will ask you to:
HIT KEY W/STABLE
+0.7120 VOLT
It may take several minutes for the volt-
age to stabilize. Once the displayed voltage
has stabilized, press the SELECT key. The
display will prompt with the following mes-
sage:
INP 4 DIGIT STD.
HI pH = 04.00
Input the pH value as a 4-digit number
(make sure you use the correct pH value cor-
32
SPAN
pH
responding to the temperature of the pH
buffer). You can alter the value of the flash-
ing digit by pressing the arrow keys up or
down. Move forward to the next digit by
pushing the SELECT key.
previous digit by pushing the EXIT key. Once
the span point has been entered, the Mark 22
will automatically respond with the follow-
ing display:
TEMP
pH
and the "TIME" option will be flashing.
5.4 H
OW TO SET
The Mark 22 uses an internal clock to
maintain date and time for recording pur-
poses. This feature allows you to record ex-
actly when a measurement was made which
can facilitate on-line system performance
evaluations over a period of months or even
years.
To set the date and time, press the SETUP
key and select the "CAL" option. Next, se-
lect the "TIME" option.
prompt with the following display:
DATE
and the "DATE" option will be flashing. Press
the SELECT key. The display will then indi-
cate the following:
INPUT
DATE
The "mm" stands for month and the "dd"
stands for day. Alter the value of the flash-
ing digit by pressing the arrow keys up or
Move back to a
COND
TIME
D T
ATE AND IME
The Mark 22 will
TIME
mmdd
0101
Martek Instruments, Inc.