Hanna Instruments HI 720 Instruction Manual page 35

The communication baud rate is set through the item P .01 and it will be the same
for any connection type.
To have an error associated with the SMS service, the proper configuration has
to be selected in the "Error Menu".
When an error configured for the SMS service is switched on, the following mes-
sage will be sent to the programmed number(s):
"Rem_msg: xxx; The following error occurred on HI720: XXXXX"
where xxx is a 3-digit number indicating the remaining messages and XXXXX
represents a text string corresponding to the activated error.
This is the list of all possible error strings:
• "High alarm"
• "Low alarm"
• "Max relay ON time error"
• "Life check error"
• "Conductivity input overflow"
• "Calibration timeout"
• "Broken temperature probe"
• "Digital transmitter error"
• Temperature compensation error"
• "Temperature outside the user concentration table"
• "Conductivity outside the user concentration table"
• "Concentration outside the user concentration table"
• "EEPROM corruption"
• "Temperature level error"
Since an SMS sometimes can be received with a considerable delay, the instru-
ment also calls the programmed phone number(s) to immediately advise the
user that something is happening on the HI 720 and an SMS is on the way.
When an alarm SMS is sent, then the instrument waits for a confirmation by the
user of message reception. The receiver should confirm by simply calling the
phone number of the GSM engine SIM card.
You can also configure the instrument for repeated sending of message if a
confirmation is not received immediately (setup items P .15 and P .16). This feature
will prevent from losing any warning massage due, for example, to the over-
charge of the telephone network. The item P .15 indicates the number of repeated
messages, while P .16 sets the delay between two subsequent messages.
A phone call from one of the programmed numbers to the instrument, is under-
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stood as an information request. The instrument will hang up the call and send
an SMS about its current status (number of remaining messages, currently mea-
sured values and active errors). The message will be, for example:
"Rem_msg: 150; 1832 uS/cm; 025.8C; Err: xxxxx, xxxxx"
Each message is made of a maximum of 160 characters. For this reason, a
coded notation is used to indicate the active errors, as listed below:
• High alarm: "HI Alarm"
• Low alarm: "LO Alarm"
• Max relay ON time error: "Rel on"
• Life check error: "Life chk"
• Conductivity input overflow: "Con over"
• Calibration timeout error: "Cal tout"
• Broken temperature probe: "Brk temp"
• Digital transmitter error: "Tx err"
• Temperature compensation error: "Tem com"
• Temperature outside the user concentration table: "Temp out"
• Conductivity outside the user concentration table: "Cond out"
• Concentration outside the user concentration table: "Conc out"
• EEPROM corruption error: "EEPr cor"
• Temperature level error: "Temp lvl"
If no error is active, the "No error" string will be sent.
If the instrument receives the information request while in hold mode, the "Hold;"
string is added before the conductivity (or concentration) indication. If the instru-
ment is performing a cleaning action, the "Cleaning;" string is added.
All information about the SIM card, such as charge and expiration date, are
managed by the network operator. To prevent the discharge of the SIM card,
manual configuration is necessary for the maximum number of SMS that can be
sent (item P .14), according to the SIM card credit.
When the maximum number is approaching zero, the message "Rem_msg: xxx;
Maximum number of SMS reached. Please check the HI720 SIM card charge level"
will be sent by the instrument to the programmed number(s). This situation is handled
as an error occurrence and confirmation of SMS reception is expected.
In this case the SIM card should be extracted from the cellular engine and the
remaining credit checked by calling the network operator with a normal cellular
phone. When a confirmation is given to the message, the "GSM/Modem mod-
ule error" is switched on and no more messages will be sent.
To close the "GSM/Modem module error", modify the setup item P .14 (the value
of this item - remaining number of available messages - is automatically
decremented each time an SMS is sent).
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