Relative Mv Calibration - Hanna Instruments HI 2214 Instruction Manual

RELATIVE mV CALIBRATION

• Press CAL when the instrument is in RELATIVE mV measurement
mode. The "mV" and " " tags will be displayed. Absolute mV is
displayed on the primary LCD and "AbS" message is displayed on the
secondary LCD.
• When the absolute reading is stable and in measurement range, the
instrument asks for confirmation.
• If the reading is out of range, "WRONG" tag will be displayed.
• Press CFM to confirm the absolute value. The instrument will display
"0.0 mV" on the primary LCD and "rEL" message on the secondary
LCD. In this moment the relative mV offset is equal to absolute mV
reading.
• Use the ARROW keys if you want to change the displayed relative
mV value.
• Press CFM to confirm the relative mV value. The relative mV
offset is displayed on the primary LCD. The instrument returns to
measurement mode.
Note: The relative mV value can be changed only inside the relative mV
offset window (± 2000 mV).
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CHR xx Change the instrument's range according to the parameter's
value (xx):
• xx=00 pH range/0.001 resolution
• xx=01 pH range/0.01 resolution
• xx=02 pH range/0.1 resolution
• xx=03 mV range
• xx=04 Relative mV range
The instrument will answer for these commands with:
<STX> <answer > <ETX>
where: <STX> is 02 ASCII code character (start of text)
<ETX> is 03 ASCII code character (end of text)
<answer>:
<ACK> is 06 ASCII code character (recognized command)
<NAK> is 21 ASCII code character (unrecognized command)
<CAN> is 24 ASCII code character (corrupted command)
COMMANDS REQUIRING AN ANSWER
The instrument will answer for these commands with:
<STX> <answer> <checksum> <ETX>
where the checksum is the bytes sum of the answer string sent as 2 ASCII
characters.
All the answer messages are with ASCII characters.
RAS Causes the instrument to send a complete set of readings in
according to the current range:
• pH, temperature and mV readings on pH range.
• Rel mV, absolute mV and temperature readings
on Relative mV range.
The answer string contains:
• Meter mode (2 chars):
• 00 - pH range (0.001 resolution)
• 01 - pH range (0.01 resolution)
• 02 - pH range (0.1 resolution)
• 03 - mV range
• 04 - Rel mV range
• Meter status (2 chars of status byte): represents an
8 bit hexadecimal encoding.
• 0x10 - temperature probe is connected
• 0x01 - new GLP data available
• 0x02 - new SETUP parameter
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