Connecting An Ac Fan; Bluetooth Header - Arduino TC4+ Quick Start Manual

HC-05
BT HDR
Figure 6: Connection of the HC-05 (left) and HC-06 (right) Bluetooth modules.
you sourced your heating element separately, I strongly recommend connecting
a suitably placed thermal fuse in series with the heater.
Important: Powering your heating element without airflow might result in
near-instantaneous overheating.
Important: Exercise care when mains voltage is, or might be, present.
3.6

Connecting an AC fan

AC fans are slightly more complex to control. There is two options of interfacing
with them: A separate PWM dimmer module (recommended), or a zero-cross
detector (beyond the scope of this guide).
To control an AC fan via a PWM dimmer module, you will need a PWM dim-
mer module. One verified option is this: https://www.tindie.com/products/
bugrovs2012/pwm-ac-light-dimmer-module-50hz-60hz
To connect this, use a three-pin cable to connect the PWM header on the
PWM dimmer board to the TC4+. 5V goes to 5V, GND goes to GND. PWM
goes to IO3. The AC side of the PWM dimmer board connects to the mains,
and to the AC fan, respectively.
Important: Exercise care when mains voltage is, or might be, present.
3.7

Bluetooth Header

The board provides a 5-pin header for a HC-05 or HC-06 Bluetooth module.
This allows wireless roast monitoring and control. With a HC-05 (but not HC-
06), you can also wirelessly upload Arduino sketches. See Figure 6 for how to
connect either module. See the configuration section for details on how to set
up the connection.
HC-06
BT HDR
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