Hanna Instruments HI 504901 - Manual (Page 20)

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Instead, in case of mains power failure (see “Power failure”
section), HI504901 issues the following alarm SMS: “Alarm!
Power failure; Rem msg: <NUMBER OF REMAINING MES-
SAGES>”. After user confirmation of message reception (see
further on), HI504901 will send back the SMS: “Power fail-
ure; Rem msg: <NUMBER OF REMAINING MESSAGES>”.
After a power failure event, when the mains power supply
comes back, the following message will be sent to the set
phone number(s) without any request: “Power is ok now; Rem
msg: <NUMBER OF REMAINING MESSAGES>” (this mes-
sage does not need confirmation by the user; see further on).
Note After submission of an alarm message, a phone call is made
by the instrument to the programmed number(s). This is done
because the SMS can be received with a considerable delay
due to network overload, while the phone call takes place
immediately and has a long ring, which is more likely to be
heard. The phone call advises the user that something hap-
pened on the HI504901 (or on one of the connected instru-
ments) and an SMS is going to be received. It is not neces-
sary to answer this phone call and it is suggested to simply
close it. When an error occurs (and an alarm SMS is sent),
the instrument wait for a confirmation of the message recep-
tion. The confirmation can be done calling the HI504901
phone number (number for voice call of the GSM module).
The interface will answer hanging up the incoming call and
send one or more SMSs about the status of all instruments
connected to the HI504901 interface (this confirmation is
managed as an information request; see further on for de-
tails). It is also possible to configure the instrument to send
repeated messages if confirmation is not received immedi-
ately (see “Repeated SMS” and “SMS delay” items in “Inter-
face configuration” section). This feature has been introduced
to prevent loosing of warning messages due for example to
overload of the telephone lines; “Repeated SMS” item repre-
sents the number of repeated SMSs to send, while “SMS de-
lay” item sets the delay time between two subsequent alarm
messages.
INFORMATION SMSs
In addition to the alarm messages already described, the cellu-
lar phone interface can send information messages upon request.
These messages include all relevant information that can be
some parameters for serial communication (as baud rate or
device RS485 address) are not correct (parameters values
probably are not the same on HI504901 and meter side;
see “Interface configuration” section).
The format of this kind of alarm message for the instruments
connected to the RS232 ports will be:
“<INSTRUMENT NAME>; RS232-<NUMBER OF THE
RS232 CHANNEL>; Alarm: Device not responding; Rem msg:
<NUMBER OF REMAINING MESSAGES>”
while for the instruments connected to the RS485 ports will be:
“<INSTRUMENT NAME>; RS485-<RS485 DEVICE AD-
DRESS>; Alarm: Device not responding; Rem msg: <NUM-
BER OF REMAINING MESSAGES>”
Alarm SMSs for instrument connected to the digital input port
If the digital input was configured to send alarm SMSs and the
present status of port matches with the condition selected for
triggering an alarm message in the last HI504901 configura-
tion (see “Interface configuration” section), then the following
SMS will be sent:
“<INSTRUMENT DESCRIPTION>; Digital input; <ALARM
DESCRIPTION>; Rem msg: <NUMBER OF REMAINING
MESSAGES>”.
Previous fields represent strings inserted by the user with the
HI504901SW software as following:
• <INSTRUMENT DESCRIPTION>: instrument description
string, maximum length is 20 characters;
• <ALARM DESCRIPTION>: alarm description string, maxi-
mum length is 30 characters.
Alarm SMSs specific to the interface
Two alarm SMSs are provided to inform the user about troubles
specific to the HI504901 interface, the first one concerning
the internal backup battery status, the second one about mains
power supply status.
If a problem was found during last battery test (see “Fault con-
ditions and selftest procedures” section), HI504901 issues the
following alarm SMS: “Alarm! Battery test failure; Rem msg:
<NUMBER OF REMAINING MESSAGES>”. After user con-
firmation of message reception (see further on), HI504901
will send back the SMS: “Battery test failure; Rem msg: <NUM-
BER OF REMAINING MESSAGES>”.