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Electrical Circuit Help needed

A customer has requested a high voltage meter hardware design, to include a 3-digit LED display, and with the following specification. This circuit is required to fit into an existing electronic system - the customer will build the circuit themselves and write the software if required. There is a 5V 1A supply available within their existing system for powering the new voltmeter circuit:

1. Vin = 0 to 450 Vdc

2. Accuracy +-2 Vdc

PLEASE NOTE THAT THIS IS A DESIGN AND DOCUMENTATION EXERCISE - YOU ARE NOT EXPECTED TO BUILD THIS CIRCUIT OR WRITE ANY CODE.

The report should include the following information:

~> An introduction and specification, including the total power dissipated by the circuit (approx. 100-200 words).

~> A fully labelled circuit diagram, including showing all external connections, component values and part numbers.

~> A circuit description (to explain how your circuit works). Include any working out e.g. include any Ohms Law or other calculations that you make.

~> A parts list table including basic component spec, Farnell Components part number, component prices and total price for all circuit components.

~> If your design uses a microcontroller board such as an Arduino or Tweeny, state which IO pins the customer has to or may use, and how they should be set up. E.g. set pin 9 to analogue input and pins 11 to 23 to digital outputs. Assume that the customer will write their own software.

Imagine that you want to impress your customer so that they give you the contract to manufacture these circuits, once the design is approved.

Therefore, the highest marks will be given for the most impressive report and circuit solution. How you do all of this is entirely up to you.

HINTS:

1. Use a potential divider to divide the dangerous voltage down to a safe voltage (we didn't study this, so look it up).

2. An ADC is needed to convert the safe voltage to a digital value (included on most microcontrollers).

3. Assume that a microcontroller e.g. Arduino Nano or Arduino Uno will be used to convert the digital value to BCD values.

What circuit would i use? Thank you
Original post by UniHelpNeeded
A customer has requested a high voltage meter hardware design, to include a 3-digit LED display, and with the following specification. This circuit is required to fit into an existing electronic system - the customer will build the circuit themselves and write the software if required. There is a 5V 1A supply available within their existing system for powering the new voltmeter circuit:

1. Vin = 0 to 450 Vdc

2. Accuracy +-2 Vdc

PLEASE NOTE THAT THIS IS A DESIGN AND DOCUMENTATION EXERCISE - YOU ARE NOT EXPECTED TO BUILD THIS CIRCUIT OR WRITE ANY CODE.

The report should include the following information:

~> An introduction and specification, including the total power dissipated by the circuit (approx. 100-200 words).

~> A fully labelled circuit diagram, including showing all external connections, component values and part numbers.

~> A circuit description (to explain how your circuit works). Include any working out e.g. include any Ohms Law or other calculations that you make.

~> A parts list table including basic component spec, Farnell Components part number, component prices and total price for all circuit components.

~> If your design uses a microcontroller board such as an Arduino or Tweeny, state which IO pins the customer has to or may use, and how they should be set up. E.g. set pin 9 to analogue input and pins 11 to 23 to digital outputs. Assume that the customer will write their own software.

Imagine that you want to impress your customer so that they give you the contract to manufacture these circuits, once the design is approved.

Therefore, the highest marks will be given for the most impressive report and circuit solution. How you do all of this is entirely up to you.

HINTS:

1. Use a potential divider to divide the dangerous voltage down to a safe voltage (we didn't study this, so look it up).

2. An ADC is needed to convert the safe voltage to a digital value (included on most microcontrollers).

3. Assume that a microcontroller e.g. Arduino Nano or Arduino Uno will be used to convert the digital value to BCD values.

What circuit would i use? Thank you

You are asking the wrong question.

I take it this is an engineering degree? It looks a bit general so I'm assuming this is a first year general engineering course and that this is for the electrical/electronic modules?

Engineering is much more than simply churning out a schematic. I suggest you first decompose the problem using an overarching systems-engineering approach to flesh out and define the specification to include things like functionality, final production quantities, integration detail within the existing equipment, reliability, safety statutory legal requirements to which the design must comply. e.g. high voltage isolation, insulation, grounding and circuit breakers, electromagnetic compatibility, environmental conditions (static or dynamic kinematics, thermal, humidity, dust ingress etc.), ergonomics -ease of use etc. You will need to look at the IEE edition 17 rules and make sure your final design complies with it. Also think about the light levels for the display readings (daylight, night-time low-light) and importantly, think about equipment failure - what happens if there is a fault? Think about the types of fault and how you may both alert and protect the user from lethal shock hazards if that happens. You may also want to consider some form of built-in-test so that the user can check the functioning of the meter in-situ before the output reading is taken by the user etc.

Do not forget the overall cost at all stages.

As with any professional engineering specification, you must include references for the documentation sources, papers, other commercial designs etc.

When you have the design specification, you will need to assess how you will test the final design with reference back to the design specification. This means nothing should be in the design which cannot be easily tested. Only when you have nailed the specification, should you attempt to produce a definition for the design - again at the systems block-level schematic level of abstraction. Include the interfacing requirements (dimensions, connectors/ pin assignments etc.

When you have the definition, produce the schematic. This will require you to consider all options and produce some form of weighted decision chart which assesses the available technologies as well as commercial off-the-shelf existing designs, together with discrete component designs.

Only then can you decide the best design to meet all of the specification requirements and most importantly safety and cost..

Don't forget, you will have to present this as a report, so make sure you précise appropriately. You can and should include all specifications and documentation referenced as appendices and supply these along with your report.

The way you go about solving this is equally as important as the design itself.

Good luck.

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