tool_access_controllers
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Table of Contents
Tool Access Controllers
Overview
PCB
https://github.com/timhawes/stony_skunk/
Revision 1 had an error in the layout and was not used.
Revision 2 uses an ESP-12E module and has been deployed on many of the lab's tools.
Revision 3 uses a Wemos D1 Mini module for easier builds and debugging.
| Ref | Item | Quantity | Selection |
|---|---|---|---|
| U1 | Wemos D1 Mini | 1 | |
| U2 | TE OJ/OJE series 5V relay | 1 | Farnell 1891661 |
| SP1 | 12.7mm through-hole buzzer | 1 | CPC LS03778 or LS00654 |
| D1 | Flyback diode | 1 | Farnell 1625280 (US1D) |
| D2 | ESD protection diode | 1 | Farnell 2317508 (ESD5Z3.3T1G) |
| Q1, Q2 | N-channel MOSFET SOT-23 | 2 | Farnell 2069541 |
| C3 | 10uF capacitor | 1 | |
| R1, R6, R7, R13 | 10K 0603 | 3 | |
| R3, R4 | 200R 0603 | 2 | Optional, values depend on current clamp |
| R5 | 1K 0603 | 1 | |
| R8, R9 | 2K2 0603 | 2 | |
| P1 | 8-way 3.5mm screw terminal | 1 | |
| P2 | 4-way 0.1“ header | 1 | |
| P3 | 2-way 5mm pluggable header | 1 | CPC CN18918 + CPC CN18994 |
| P4 | 5-way 0.1” header | 1 | |
| P7 | 2-way 0.1“ header | 1 |
Other Components
To make a working system, the following components will be required in addition to the PCB:
| 20×4 LCD module with I2C backpack | by convention we use black text on a yellow backlight, which is more readable than white on blue |
| PN532 NFC module | Buy direct from Elechouse, clones have poor read range and a high failure rate |
| Two push buttons | CPC SW03314 |
| Current transformer | DL-CT08CL5-20A plus 33R burden resistor |
Depending on the tool being managed:
| 5V 1A power supply | 240V AC-DC, 24V DC-DC from a VFD or 5V from an existing PSU |
| AC contactor or no-volt switch |
Enclosure and Wiring
All of our current tool controllers use the same design, an IP65 ABS enclosure from RadioWorld on eBay.
The PCB, LCD and NFC modules are mounted on a laser-cut acrylic frame using nylon screws and spacers.
Software
Two generations of firmware and backend-server are in use at the moment:
Legacy/Stable:
- uses UDP networking with a simple retry mechanism for reliability
New:
- uses TCP networking with optional TLS support
tool_access_controllers.1550928040.txt.gz · Last modified: 2019-02-23 13:20 by tim