The product shown is a remote monitoring unit, which monitors the liquid levels in a container based on the sensor readings. This unit works on a 9V battery supply .The design of this unit is done to have a longer battery life by optimizing the current consumed .The Controller used for this unit is PIC18F452 (Microchip) and compiler used is HI-TECH software. The various sensor types are Voltage, pressure, and two-wire resistor, three-wire resistor, galvanic. The sensor readings are converted into equivalent units based on a linearisation table. The status of the inputs are notified to the server with the help of modem connected to a POTS line on any of the following settable schedules.
The objective of this project is to design and develop a remote monitoring unit, which monitors the liquid level in a container by means of sensors and notifies the same to a remote server through modem connected to a POTS line.
The various user settable parameters like alarm limits, tank setup, remote server phone number, Processor Wake up parameters and communication failure parameter are set during installation using a PC RS232 interface.
InfoTech designed and developed the hardware to obtain the desired
functionality using:
- Microchip 18F452 processor.
- Circuitry for compatibility with sensor types (Pressure, Galvanic, Voltage, Temperature, Two-Wire and Three-Wire).
- A real time clock to enable wake up of the processor at desired time.
- A TDK semiconductor based modem card for the communication with the remote server via POTS line.
- Serial (RS232) interface circuitry.
- A human interface console with push buttons, seven-segment display and LEDs.
The firmware development was carried out using Hi-tech C cross compiler. The enclosure design was developed using Auto-CAD software and the manufacturing of the same was sub-contracted.
- Field Programmability via Serial (RS232) Interface
- Communication to the remote server via modem connected to POTS line
- Report Scheduler:
Ability to scan the sensor input at regular interval (settable by user)
and notify the server in case of any alarm detection.
Ability to connect to the server at specified time of the day or week
(settable by user).
- Local Operator Interface:
A seven-segment display to give a quick update on the level of liquid.
Alarm Status Indicator - A manual provision to detect alarms LED indication
of the status of alarm and notify to server if any alarm found.
- Firmware update capability via modem or RS232
- Weather Resistant NEMA 4 Enclosure.
- Uses a 9 V Battery Pack with lifetime of five years.
- Compatible with a wide range of sensors.
- Programmable alarm dialer.
- Auto configuration of EPBAX telephone lines.
- Inputs:
Two Analog inputs
Four Dry contact inputs
- Longer product life by optimizing current consumption of the unit.
- Low cost of BOM.
- Project executed in a less time frame.
Ease of firmware update for future enhancement.
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