Hach MP-4, User Manual

Page: 32 / 60

Calibration
32
6.
Push the
CAL/MCLR
key to accept the new calibration value. The meter
accepts the value and presents the next value for adjustment. If there are no
more adjustments, the meter exits CAL mode.
Note:
In the CAL mode, the
CAL/MCLR
key becomes an
ACCEPT
key. To bypass a
calibration step, push the
CAL/MCLR
key to accept the present value.
4.5 Exit calibration mode
When the
CAL
icon turns off, calibration is complete. To exit calibration mode when
the
CAL
icon is still on, push any measurement key. This cancels any changes not
accepted and exits the CAL mode. When CAL mode for pH is exited after the
second buffer, the meter enters the same gain for the third buffer.
4.6 Calibrate conductivity, mineral/salt or TDS
To make sure calibration is accurate, follow the items listed below.
1.
Clean oily films or organic material from the conductivity cell with foaming
cleaner or mild acid.
2.
Do not scrub inside the conductivity cell.
3.
Rinse the conductivity cup with pure water after taking measurements.
4.
Rinse the conductivity cup three times with the standard solution to be used for
calibration (KCl, NaCl, or 442).
Note:
Failure to rinse can cause crystals to form in the cup and contaminate future
samples.
5.
Fill the conductivity cup with same standard.
6.
Push the
COND
key, the
MIN/SALT
key or the
TDS
key.
7.
Push the
CAL/MCLR
key. The
CAL
icon appears on the display.
8.
Push the
UP/MS
key or the
MR/DOWN
key to adjust to the standard value, or
hold down the key to adjust rapidly.
9.
Push the
CAL/MCLR
key once to confirm the new value and end the
calibration sequence for this solution type.
10.
To calibrate another solution type, change solution type (e.g., KCl, NaCl, or
442) and repeat this procedure.
Parameter KCl, NaCl or 442 User
COND Gain only Temperature compensation, then Gain
RES Done in conductivity Done in conductivity or TDS
TDS Gain only
Temperature compensation, Ratio,
then Gain
MIN/SALT Gain only
Temperature compensation, Ratio,
then Gain
pH 7, acid, and/or base
ORP Zero set with pH 7 automatically