Overview

The RPIZCT4V3T2 can be configured to read both single phase and 3 phase systems.

Several temperature sensors can be interfaced. It has support for both DS18B20 temperature sensor and RTD thermocouples.

It is designed to host a user provided Raspberrypi zero.

The main PCB has provision for one extra mezzanine card to extend the number of sensors.

An enclosure solution is proposed using aluminium extruded case.

Specifications

cpu

Hosts RaspberryPi Zero
ATmega328 mcu (Arduino UNO)

Sensors

4 CT sensors
3 AC Voltage
1 DS18B20 port (temperature)
1 RTD Thermocouple port

Power

Powered from Raspberrypi (microusb)

Other

Fits in Aluminium Enclosure from Evatron
Option to stack mezzanine board for additional sensors.

Recommended sensors

AC Current sensor:
- SCT-013-000
- SCT-019
- SCT-006
AC Voltage sensor:
- UK: 77DB-06-09
- EU: 77DE-06-09
- US: 77DA-10-09
- ZMPT101B
Temperature:
- DS18B20
Temperature RTD:
- PT100
- PT1000 (modification required)

Temperature Sensor

DS18B20

The temperature port supports mutiple sensor on the same Onewire line.

The sketch is programmed to search for all connected probe at bootup and output all their values when polled. If a new probe is connected the arduino mcu should be restarted for the new probe to be registered.

Multiple probes should connected as shown below.

RTD Thermocouple

A MAX31865 RTD module is used to interface the RTD sensor with the arduino controller.

There is support for 2 3 and 4 wires thermocouples. Also both PT100 and PT1000 can be used.

Units are sold by default setup for 3 wires PT100 units. Other setup can be configured and require some basic soldering. Full details to configure the MAX31865 module are given by ADafruit webpage here. https://learn.adafruit.com/adafruit-max31865-rtd-pt100-amplifier/rtd-wiring-config

Software Configuration

The documentation for serial configuration can be found on this page.
Over Serial Configuration - Sketch 2.0

The default configuration can be obtained using the command

wget lechacal.com/RPICT/config/B4/rpiz_ct4v3t2.conf

The online configurator can be used with the RPIZ_CT4V3T2. Use a single board of RPICT4V3 when editing the configuration.

Online configurator.

Mezzanine Boards

RPIZ_CT4V3T2 has provision to stack an extra mezzanine board to extend the number of sensors. We currently have 2 type of mezzanine.

Generic Mezzanine

This is a basic board extending all unused I/O pins of the Arduino microcontroller. These are presented as male pin header. Ground and 5V are also available for each pin.

This will only be used if you are planning to write your own firmware.

Each available pins are listed below.


Atmel Pin	Arduino Analog	Arduino Digital
PC0	A0	D14
PC1	A1	D15
PC2	A2	D16
PC3	A3	D17
PC4	A4	D18
PC5	A5	D19
ADC6	A6	-
ADC7	A7	-
PD2	-	D2
PD3	-	D3

CT8 Mezzanine

The CT8 mezzanine offers an extra 8 CT connection with a 12 bit ADC. Increasing the total number of CT to 12.

Enclosure

The board has been designed to fit inside an aluminium extruded enclosure. 3D printed end plates are provided. Enclosure kit is available in the shop.