09 Building/wiring
All touchable metal parts need to be grounded, especially the heat sinks.
Wire thickness
Rule of thumb: max. 10 A/mm² copper (this is AREA, not diameter or radius)
At maximum rating, dissipation in the cable will be quite high, temperature inside housing can rise quite high and life span of some components can be reduced. So it is advisable to choose a wire type that is one size larger.
"one size larger" table
7 A -> 1 mm2 ( 1.5 kw load at 230V)
10 A -> 1.5 mm² ( 2.3 kw load at 230V)
16 A -> 2.5 mm² ( 3.7 kw load at 230V)
24 A -> 4 mm2 ( 5.5 kw load at 230V)
50 A -> 10 mm2 (12 kw load at 230V)
80 A -> 16 mm2 (18 kw load at 230V)
Or see below. The column "up to 3 cores" is relevant, because the wires lie closely together.
https://www.engineeringtoolbox.com/wire-gauges-d_419.html
https://www.powerstream.com/Wire_Size.htm
Mounting triacs and SSRs
Spread the parts evenly over the heatsink, in order to spread the heat.
Threaded holes in the heatsink make installation easier.
- Drill a 3.2mm hole
- Turn the thread with a 4mm thread cutter. If you have a thread cutter set with 3 cutters per diameter, the middle one is best, because aluminum is relatively soft. Your screw will turn tightly, but it will hold better.
- Clean the edge of the hole with a bigger drill bit, so the surface is plane (important!)
- Apply heat sink grease to the triac. Not too much - just enough so it squeezes out on the edges while tightening.
- Fasten the triac with the 4mm screw and washer spring ring. Don't tighten too much, or else the triac will bend slightly, and the heat transfer will actually become worse. Hexagon (Allen) screws are easiest to handle, but others will work.
- Bend the pins. For the second bend, hold the pin with pliers close to the casing, to avoid breaking off the pin.
- Do the electrical connections. See images below.
Phase angle Triacs
The inductivity needs 8 windings. That is, the cable needs to go through the hole 8 times.
SSRS
For SSRs, use 5mm or 6mm screws.
You can also use nuts instead of threaded holes (or if your thread is broken :-). Both systems work.
Connectors
The wire assignments of the cables and all connectors are also printed on the PCB.
Triac connector
SSR connector
SSrs are low side switched (switched to gnd) by a NPN transistor on the PCB.
They need to accept 5V control voltage input.
They can be connected directly to the connector.
Relay connector
2 Modules, each Module with 4 Relays.
DO NOT CONNECT RELAYS DIRECTLY.
This connector comes directly from the microcontroller, so all protection elements like diodes and power transistor/optocoupler need to be present on the relay module.
5V connector
Mains connector
AD input connector
Todo:
Ethernet connector
GSM connector
Serial connector
ICSP SPI connector
I2C connector
Keypad connector
Display connector
Double row flat ribbon cable connectors
These are IDC insulation displacement connectors (German Schneid-Klemm-Technik). You will an IDC pliers tool, or a bench vice (american english: vise)
Relays
For the single row connectors, which go on the relay PCB, you will need crimp contacts and preferrably a crimp tool.The jumper on the relay PCB connects Vcc and JDVcc.
JDVcc is the power supply for the relays. Vcc is the power from the connector. In our case, the relays are powered from the main 5V source coming from the connector. There are free wheeling diodes on the relay PCB. So using the same power supply is okay.
Unfortunately, the relay PCB connector is not boxed. Make sure you plug in the socket the right way round.