IONO PI Server based on Raspberry PI 4 relay 2 in analog 7 IO digital RTC

MANUAL | QUICK REFERENCE

Iono Pi comes pre-assembled with a Raspberry Pi 4 and an Iono Pi RTC board, in a standard 4-module plastic DIN housing. MicroSD not included.

Iono Pi is an extremely versatile Input / Output module with a very powerful processing core based on a standard Raspberry Pi.

Combine multiple digital and analog input lines, support for standard interfaces such as 1-Wire and Wiegand, and power relays, typical of a modern PLC, with the incredibly powerful 1.2GHz 64-bit ARM Cortex-A53 quad-core processor of the Raspberry Pi 4.

Iono Pi adds other important features that are essential for using the Raspberry Pi for professional applications, such as a robust power supply with a wide voltage range (9-28V) capable of delivering up to 3A of current at 5V.

This version has an RTC clock to keep the system date and time even in the absence of power.

Iono PI is available with or without RTC module, with DIN case and pre-assembled. Discover all the products in our shop on EBAY | MECTRONICA STORE

Features:

• Pre-assembled and tested Raspberry Pi 4 model with Iono Pi RTC board, in a standard 4-module box
• Side access to HDMI and 3.5mm jack for composite audio and video
• access to all USB ports and the Ethernet port (opposite to the power supply and serial terminal block)
• compliant with 2014/35 / EU (low voltage), 2014/30 / EU (EMC), EN61000-6-2: 2005 (EMC immunity), EN60664-1: 2007 (electrical safety), EN61000-6-3: 2007 (Emissions) and 2011/65 / EU (RoHS).

•          9 ÷ 28Vdc power supply, with overvoltage and polarity inversion protection and 1.1 A resettable fuse
•          up to 2.5A maximum current at the input pins of the Raspberry Pi 5V (at 24Vdc) power supply
•          4 relay outputs rated for 6 A at 250 V
•          2 analog voltage inputs 0 ÷ 30V
•          2 analog voltage inputs 0 ÷ 3V on internal pin-headers
•          7 configurable digital input / output pins
•          1-Wire and Wiegand support
•          Real Time Clock to keep system time even in the absence of power
•          2 built-in LEDs, one for power and one controlled by the Pi's GPIO line
•          power supply and I / O connections on screw terminal block
•          compliant with 2014/35 / EU (low voltage), 2014/30 / EU (EMC), EN61000-6-2: 2005 (EMC immunity), EN60664-1: 2007 (electrical safety), EN61000-6-3: 2007 (Emissions) and 2011/65 / EU (RoHS).

Iono Pi can be used for an incredible range of applications, from data acquisition and control, to home and building automation, as well as access control, hotel room control solutions, environmental monitoring and many more. still others. And software development is pure Raspberry Pi, with the ever-growing list of standard and proprietary software frameworks available on this platform.

Iono Pi can be used in both industrial and residential environments, for professional applications where extreme reliability, robustness and compliance with technical and safety directives are required.

It complies with the 2014/35 / EU (Low voltage) and 2014/30 / EU (EMC) CE directives and the harmonized standards for electromagnetic compatibility (EN61000-6-2: 2005), electrical safety (EN60664-1: 2007 ), emission (EN61000-6-3: 2007) and RoHS directive for hazardous substances (2011/65 / EU). It also complies with part 15 of the FCC Rules (Class A), ICES-003 (A) and CISPR 32: 2015 (Class A).

Power supply

The power stage is a highly protected and filtered circuit, which uses oversized electrolytic capacitors, diodes and inductors, and a high efficiency, high power voltage regulator, capable of delivering up to 2.5A on the power input to 5V of the Raspberry Pi. The Iono Pi accepts a wide power range, from 9 to 28 Vdc, and can effectively handle large amounts of power voltage fluctuations, noise and fluctuations.

Relay

Iono Pi has 4 power relay outputs with normally open contacts, rated at 6A at 250V, which can tolerate peak currents (inrush current) up to 15A.

These relays have a minimum mechanical life of 5,000,000 operations.

The relays are controlled by the Raspberry Pi's 4 GPIO output pins, so they are very easy to control from any software development environment or application.

The relays ensure 5kV insulation between coil and contacts (1.2 / 50 μs voltage wave), protecting the Iono Pi circuit and the Raspberry Pi from external overvoltages.

The relay coils are 12Vdc, therefore a special limiter circuit inside the Iono Pi module limits the voltage when the power applied is greater than this value; this circuit also has a very low saturation voltage when the applied supply voltage is 12 Vdc or less.

Analog inputs

Iono Pi has two dedicated analog inputs on the low voltage terminal block. The voltage input range is 0-30V. We use Microchip's MCP3204 12-Channel A / D Converter to convert analog voltage to digital. The converter is connected to the Raspberry Pi via the SPI serial interface. The MCP3204 is a very well supported chip, particularly easy to use from the software on the Raspberry Pi. The 12-bit A / D converter offers good resolution and sampling rate.

The two additional inputs of the A / D converter are available on an internal header for custom extensions. These inputs do not have a voltage divider before the converter inputs and accept a voltage range of 0-3V.

Digital inputs

Up to 6 pins can be used as digital inputs and wired, via a protective network, to the Raspberry Pi's 6-pin GPIO. By applying a positive voltage (up to 40Vdc) to these pins, the corresponding GPIO pin will be high. Three of the digital input pins are shared with the open collector outputs, while the remaining three can be reconfigured as TTL I / O lines.

All inputs are protected by a network of resistors and Schottky barrier diodes to ensure that the Raspberry Pi's input pins never receive voltages significantly above 3V or below 0V.

Open collector outputs

Three of the Raspberry Pi's GPIO pins are connected to discrete open collector drivers with a maximum output current of 100mA. These outputs are individually protected against overcurrent and short circuits.

When the overcurrent protection is activated, the output will open, interrupting the flow of current. A simple reset to 0 of the Raspberry Pi GPIO pin will reset the protection.

I / O TTL - Wiegand - 1-Wire

Up to 4 terminal pins can be used as bidirectional (0-5V) TTL I / O lines, connected to the Raspberry Pi's GPIO pins via a bidirectional switching device.

These lines are suitable for interfacing with up to four 1-Wire buses or up to two Wiegand devices.

Real time clock

Iono Pi is equipped with a real time clock / calendar with buffer battery, connected to the Raspberry board through the I2C bus interface. Automatic switching to a lithium battery ensures RTC functionality when the main power fails.

The real time clock is based on Microchip's generic MCP79410 RTCC chip. It is connected to the I2C bus of the Raspberry Pi and, in addition to the standard clock function, has many other advanced functions.

A CR1220 lithium battery is used as a backup power source when main power is not available.

If the Iono Pi card is always powered, this battery should last for over 10 years. While the battery is soldered to the board, it is not difficult to replace.

Mechanical construction

The Iono Pi server is housed in a standard DIN enclosure with omega rail mounts. The case is 4 modules wide, equivalent to 71.0 mm.

The Iono Pi board is mounted on the top of the Raspberry Pi. Due to the large number of pins on the low voltage terminal block, it has a slightly larger footprint than the Raspberry Pi board.

The low voltage terminal block, with a 0.15 inch (3.81 mm) pitch, is located on the same side as the USB and Ethernet ports of the Pi. The high current terminal block for the relay contact outputs is on the other side and has a pitch larger than 0.2mm (5.08mm).

A high quality 4-layer printed circuit board is used to pack all the components of the Iono Pi into a relatively small board.

All of the Pi's GPIO pins are used by the Iono Pi board, so the GPIO connector is not pass-through.

A special cutout on the printed circuit around the power relays guarantees the required insulation distances, even in such a small footprint.