Differences between revisions 13 and 14
Revision 13 as of 2011-11-27 20:34:56
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Editor: BobAdamson
Comment:
Revision 14 as of 2011-11-27 20:47:13
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Editor: BobAdamson
Comment:
Deletions are marked like this. Additions are marked like this.
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 . http://www.ebay.com.au/itm/0-5mm-9-Core-Irrigation-Cable-per-metre-/300341913942 (for front switches and LED's)

Aims

  • redo all internal wiring and logic, except the refrigeration parts
  • make the machine more safe by doing things properly and reducing the voltage of exposed components
  • keep the software interface as simple or more simple than before
  • make the buttons on the front of the machine work for dispense
  • make it extensible so things can be added on
  • give the machine a general service where necessary (seals, rust protection, oil)

Draft Bill of Materials

Amount

Item

Use

Model

Cost

7

microswitches

front button switches

20

microswitches

each slot has double microswitches, there are 10 slots

7

5mm round white LED's

replace empty slot globes

7

led mounts for empty slot display

may not be needed, depends on how we mount the LEDs

7

resistors

empty slot LED protection

1

stripboard or veroboard

mount LED resistors

10

6 pin connectors

one for each slot actuator unit

??

? pin connectors

assorted connections between cables

1

manual drop button

1

PLC

brain

FMD88-10

1

PLC expansion card

additional IO

EXP1616R

50m?

20 different coloured wires

general rewiring

cable ties

cable loom/heatshrink tube/electrical tape

terminal blocks

1

can rust proofing spraypaint

1

110V fan to replace 12V case fan

Internal PLC IO Requirements

  • 10x24V DC input for can sensing (would it be worth multiplexing this?)
  • 7x24V DC input for front door buttons (ditto with the multiplexing question)
  • 1x24V DC input for manual dispense mode button
  • 10x?110V? relay outputs (this assumes linear actuators return by themselves)
  • 7x DC outputs for empty slot display

Process

  • empty the machine and bring it into the clubroom. This means everything won't have to be packed up at the end of the day while we're working on it
  • remove one of the stacks and test a slot actuator to see what it runs off. This determines what hardware we use to drive everything, so we need to know.
  • purchase all required hardware (PLC, wiring, connectors, switches, etc.)
  • write software (state machine based programming implemented in ladder logic, should be quite trivial)

  • wire up on the bench and test
  • service the machine. A can of zinc spraypaint wouldn't go astray on some of the rust spots I think. Check all the seals. Oil what needs oiling. Clean what needs cleaning.
  • install everything into the machine and test