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We are seeking a talented and creative digital electronics designer to help us develop an exciting electronic device and a range of optional sub-devices.
Our system is currently based on a Fatek programmable relay which is used to control a series of valves and 240VAC single phase electric motors up to 2,400 watts.
We plan to develop a second generation product based around a PIC micro controller or similar device. The finished PCB requires multiple digital and analogue inputs and numerous outputs to control 240VAC as well as various other external low voltages, devices, and indicators such as solenoids and LEDs.
The master device will manage various sub-devices and communicate with them via an RS-485 communications link and/or a Zigbee style wireless system. These sub-devices are optional and will also require development once the main controller is under way. The system must be capable of recognising that a sub-device has been attached, integrate its function into the overall system and operate correctly without user intervention.
The device should be built on a single PCB with an expansion socket to accommodate a daughter board capable of providing additional I/O capacity or for the insertion of currently unspecified expansion module.
The PCB layout should be designed to minimise physical connections to the main board and the external devices and indicators in an effort to reduce assembly costs as much as possible.
The system will require connectivity to Ethernet networks via cable (preferably) or Wi-Fi. This connection will be used to send automated emails to advise system status and operational performance and also to allow remote system management and firmware updates.
As part of the design project, a programming and diagnostic device will also be required to allow tradesmen to service the master controller ‘in-situ’ and undertake simple firmware updates on-site.
Additionally, some devices will require wireless communication with sensors and motors that could be located up to [url removed, login to view] away from the base unit. These will need to be capable of monitoring the quality of the radio link and responding accordingly.
We would prefer to engage a contractor that is capable of designing the circuit, preparing the PCB artwork and writing/debugging the software required.
Operating voltage - 12VDC to allow battery operation in remote locations
Analogue Inputs - 4, (0 to 10 volts) for transducer input
Digital inputs - 4, to count pulses for measurement calculations
ON/Off - 16, for monitoring switches and various switched inputs
On/Off outputs - 16, for controlling LEDs, relays, and various modules
RS-485 coms port - 1, for communications between the master controller and sub-devices
More detailed specification will be provided to short-listed applicants.
Would you please provide brief details of your design experience and links to any microcontroller projects that you have undertaken.
26 freelancers are bidding on average $4896 for this job
I am many years in designing control hard- and software in Asphalt- and Concrete manufacturing industry. Over the time I have my circuit portfolio for RS485, I/O ports a.o. See my project portfolio here.