RPI DCV8

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Link to the shop.

RPI_DCV8 is a 8 channels acquisition board for Raspberrypi. Any of AC current & voltage or DC current & voltage can be setup at assembly/purchase time.

  • 8 Channels.
  • Instrumentation amplifiers.
  • Measure RMS or Average signal.
  • Fit on Raspberrypi 4 holes mounting pattern.
  • Atmega328p Mcu (Arduino UNO)
  • MCP3208 ADC (12bits)
  • Screw Terminal connectors.

IMG 2062 small.pngIMG 2063 small.pngIMG 2064 small.png


Hardware Channel Setup

The idea of the RPI_DCV8 brings a customisable base to setup each channel as per your requirement. We will setup the channel type and range at purchase time. Currently supported type of channels are:

  • AC Current (using both Voltage and Current CT).
  • AC Voltage.
  • DC Current.
  • Dc Voltage.
  • Thermocouple.

DC Current

N22837947A 1.jpg

DC current can be read using a Clamp meter suitable for DC.

BT-605A

With the BT-605A currents up to 600A can be measured.
The amplification stage can be adapted on the RPI_DCV8 to adjust for desired range.


IMG 2080 small.png

AC Current

269.jpg

For measuring AC current current a Current Transformer (CT) must be used.

RPI_DCV8 can host the burden resistor for current output CT.







AC Voltage

AC/AC Transformers

Recommended models are

  • UK: 77DB-06-09
  • EU: 77DE-06-09
  • US: 77DA-10-09

ZMPT101B Module

Arduino Firmware

The RPI_DCV8 operate with an Atmel microcontroller programmable with Arduino.

A default sketch (firmware) is provided to read AC and DC readings.

Raspberrypi Communication

The RPI_DCV8 interface with the Raspberrypi using the serial uart. Data can be simply read by reading the serial port. You will find more details about the raspberrypi setup in the following link. Howto setup Raspbian for serial read

RPI_DCV8 configuration

The RPI_DCV8 has many configuration parameters. Some of them are

  • Polling interval.
  • Order of Channel to ouput.
  • RealPower, ApparentPower, Power factor if in AC reading.
  • Frequency.
  • Irms.
  • Average value for D.C reading.
  • Length of applied average.
  • and more...

A web interface to help configuring the board will be out soon.

An example of the configuration file below.


[main]
format = 3
nodeid = 11
polling = 1000
N_cvpair = 1
kcal = 30.00 83.33 83.33 83.33 83.33 83.33 83.33 83.33
phasecal = 0
vest = 240.0
xpFREQ = 50
Ncycle = 20
HWSCT = 0 6 5 4 3 2 1 0
HWVOL = 127 127 127 127 127 127 127 127
N_node_average = 8
N_samp_average = 100
K_SENSITIVITY = 1000 1000 1000 1000 1000 1000 1000 1000
K_OFFSET = 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 
HW_ave = 7 6 5 4 3 2 1 0
Nchan = 9
CHTYPE = 9 9 9 9 9 9 9 9 5 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255
CHID = 0 1 2 3 4 5 6 7 0 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255   255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255
debug = 0

Files

Sketch

Version 1.0.0 to come up soon.