OMC-042 / 043 / 044 Data loggers
Users
’ manual
page 81
A user wants to connect a large number of INW CT2X sensors to an OMC-042. This sensor measures
temperature and conductivity. So each
sensor “uses” two parameters. Also he likes to send the data via
FTP, and he enables the following internal sensors: Rest Capacity, Battery Voltage, and Current. So,
besides the Sensor drivers there are 2 drivers needed:
-
Internal Driver
-
Output Driver
So the maximum number of Sensor-drivers is: 16
– 2 = 14
So there are 14 Sensor-drivers left for use with the CT2x sensors.
The total number of parameters is: 14 * 2 + 3= 31
So the number of parameters is no problem (31 < 64)
He can connect 14 CT2X sensors max.
Power Switch Limitations
The Power Switch is capable of powering sensors up to 100 mA. The output voltage is 12 Volts DC.
Modem
The modem inside the OMC-042 and OMC-043 is capable of GPRS and GSM communications. It has
quad band support, so it can be
used worldwide. For selecting the proper frequency band, use the “modem
settings” in the configuration menu. In most cases GPRS communication is requested, so use a GPRS
enabled SIM-card to inhibit this operation. Consult your local telecom provider for the right SIM-Card and
–
settings. If GSM communication is requested, use a GSM-DATA subscription. GSM communication is
suitable for modem dial in communication. We strongly advise to activate this option in the SIM cards used
in the logger. This is often used to re-configure a logger, remotely, or to monitor actual values. In most
cases, normal GPRS communication is sufficient for the operation of the data logger.
The modem inside the OMC-043 is capable of 900MHz/2100Mhz 3G communication as used in the EMEA
and APAC regions.
Modem Firmware Upgrade
The modem inside the data logger is equipped with the latest firmware-version available. There is no need
for upgrading the software, even in the near future we don’t expect this to be needed. But just in the unlikely
event of the need of a modem firmware, it is possible to do so. This can be done with the modem mounted
on the board (in circuit programming). The procedure of upgrading modem firmware is not covered in this
manual. For more information, consult your local Observator Instruments dealer.
SD-card
The SD-card used with the data logger is a SANDISK 2GB/4GB type Card. It is formatted in FAT 32, and
is compatible for use with a PC. Don’t use other cards than this type, because the performance of the data
logger may be harmed. (This is because of the speed of the SD-card, and even the low power performance
can be affected by using a slower card). The contents of the card may be read on a PC by using a card
adaptor, or can be downloaded from the card, by using the menu-
option “Data-download”. We recommend
not removing the SD-card from the logger.
Inserting an SD-card
At the factory, the SD-card is already installed, but when the cards need to be re-inserted, pay attention to
the orientation of it. It should be inserted with the (gold-plated) terminals up.